Chapter 20: Esophagus & Diaphragm

ANATOMY

The esophagus (Figure 20–1) is a muscular tube that serves as a conduit for the passage of food and fluids from the pharynx to the stomach. It originates at the level of the sixth cervical vertebra, posterior to the cricoid cartilage. In the thorax, the esophagus passes behind the aortic arch and the left main stem bronchus, enters the abdomen through the esophageal hiatus of the diaphragm, and terminates in the fundus of the stomach. Its muscle fibers originate from the cricoid cartilage and pharynx above and interdigitate with those of the stomach below. About 2-4 cm of the esophagus is normally located below the diaphragm. The junction between the esophagus and stomach is maintained in its normal intra-abdominal position by the reflection of the peritoneum onto the stomach and of the phrenoesophageal ligament onto the esophagus. The latter is a fibroelastic membrane that lies beneath the peritoneum, on the inferior surface of the diaphragm. When it reaches the esophageal hiatus, the ligament is reflected in an orad direction onto the lower esophagus, where it inserts into the circular muscle layer above the gastroesophageal sphincter, 2-4 cm above the diaphragm.

Three anatomic areas of narrowing occur in the esophagus: (1) at the level of the cricoid cartilage (pharyngoesophageal or upper esophageal sphincter [UES]); (2) in the mid thorax, from compression by the aortic arch and the left main stem bronchus; and (3) at the level of the esophageal hiatus of the diaphragm (gastroesophageal or lower esophageal sphincter [LES]).

In the adult, the distance as measured from the upper incisor teeth to the cricopharyngeus muscle is 15-20 cm; to the aortic arch, 20-25 cm; to the inferior pulmonary vein, 30-35 cm; and to the gastroesophageal junction, approximately 40-45 cm.

The mucosal lining of the esophagus consists of stratified squamous epithelium that contains scattered mucous glands throughout. The musculature of the pharynx and upper third of the esophagus is skeletal in type (striated muscle); the remainder is smooth muscle. Physiologically, the entire organ behaves as a single functioning unit, so that no distinction can be made between the upper and lower esophagus from the standpoint of propulsive activity. As in the intestinal tract, the muscle fibers are arranged into inner circular and outer longitudinal layers. The esophagus has no serosal layer. The arterial supply to the esophagus is quite consistent. The upper end is supplied by branches from the inferior thyroid arteries. The thoracic portion receives blood from the bronchial arteries and from esophageal branches originating directly from the aorta. The intercostal arteries may also contribute. The diaphragmatic and abdominal segments are nourished by the left inferior phrenic artery and by the esophageal branches of the left gastric artery. The venous drainage is more complex and variable. The most important veins are those that drain the lower esophagus. Blood from this region passes into the esophageal branches of the coronary vein, a tributary of the portal vein. This connection constitutes a direct communication between the portal circulation and the venous drainage of the lower esophagus and upper stomach. When there is portal hypertension, as in cirrhosis of the liver, blood is shunted upward through the coronary vein and the esophageal venous plexus to eventually pass by way of the azygos vein into the superior vena cava. The esophageal veins may eventually form varices as they become distended when portal hypertension is present.

PHYSIOLOGY

The coordinated activity of the UES, the esophageal body and the LES is responsible for the motor function of the esophagus.

1. Upper Esophageal Sphincter

The UES receives motor innervation directly from the brain (nucleus ambiguous). The sphincter is continuously in a state of tonic contraction, with a resting pressure of about 100 mm Hg (anteroposterior axis). The sphincter prevents passage of air from the pharynx into the esophagus and reflux of esophageal contents into the pharynx. During swallowing, a food bolus is moved by the tongue into the pharynx, which contracts while the UES relaxes. After the food bolus has reached the esophagus, the UES regains its resting tone (Figure 20–2).

2. Esophageal Body

When food passes through the UES, a contraction is initiated in the upper esophagus, which progresses distally toward the stomach. The wave initiated by swallowing is referred as primary peristalsis (Figure 20–2). It travels at a speed of 3-4 cm/s and reaches amplitudes of 60-140 mm Hg in the distal esophagus. Local stimulation by distention at any point in the body of the esophagus will elicit a peristaltic wave from the point of stimulus. This is called secondary peristalsis and aids esophageal emptying when the primary wave has failed to clear the lumen of ingested food, or when gastric contents reflux from the stomach. Tertiary waves are considered abnormal, but they are frequently seen in elderly subjects who have no symptoms of esophageal disease.

3. Lower Esophageal Sphincter

The LES measures 3-4 cm in length and its resting pressure ranges between 15 and 24 mm Hg. At the time of swallowing, the LES relaxes for 5-10 seconds to allow the food bolus to enter the stomach and then regains its resting tone (Figure 20–2). The LES relaxation is mediated by vasoactive intestinal polypeptide and nitric oxide, both nonadrenergic, noncholinergic neurotransmitters. The resting tone depends mainly on intrinsic myogenic activity. The LES has a tendency to relax periodically at times independent from swallowing. These periodic relaxations are called transient lower esophageal sphincter relaxations to distinguish them from relaxations triggered by swallows. The cause of these transient relaxations is not known, but gastric distention probably plays a role. Transient LES relaxations account for the small amount of physiologic gastroesophageal reflux present in any individual, and are also the most common cause of reflux in patients with gastroesophageal reflux disease (GERD). Decrease in length or pressure of the LES (or both) is responsible for abnormal reflux in the remaining patients. Overall, it is thought that while transient LES relaxation is the most common mechanism of reflux in volunteers and patients with either absent or mild esophagitis, the prevalence of a mechanically defective sphincter (hypotensive and short) increases in patients with severe esophagitis, particularly when Barrett metaplasia is present. The crus of the esophageal hiatus of the diaphragm contributes to the resting pressure of the LES. This pinchcock action of the diaphragm is particularly important because it protects against reflux caused by sudden increases of intra-abdominal pressure, such as with coughing or bending. This synergistic action of the diaphragm is lost when a sliding hiatal hernia is present, as the gastroesophageal junction is displaced above the diaphragm (Figure 20–3).

DIAGNOSTIC APPROACH TO ESOPHAGEAL DISEASES

Symptomatic Evaluation

Esophageal symptoms can be divided into two groups: (1) typical, such as dysphagia, heartburn, and regurgitation and (2) atypical such as chest pain, cough, and hoarseness (Table 20–1). Dysphagia is a unique symptom as it points to an esophageal disorder, either functional (secondary to abnormalities of esophageal peristalsis or lack of coordination between different parts of the esophagus) or mechanical (secondary to a peptic or malignant stricture or an intraluminal mass). Heartburn can also be caused by non-esophageal disorders such as biliary disease, irritable bowel syndrome, coronary artery disease, and psychiatric diseases.

Upper Gastrointestinal Series

The upper gastrointestinal series test is performed by giving the patient barium to swallow. Subsequently, multiple images are taken, including the esophagus, the gastroesophageal junction, the stomach, and the duodenum (a barium swallow focuses just on the esophagus and the gastroesophageal junction). This test characterizes a hiatal hernia, an esophageal stricture, an esophageal diverticulum, or an intraluminal mass. A cine-esophagram is instead a dynamic evaluation of the swallowing process, and it is particularly useful in patients with functional dysphagia (secondary to a motility disorder, in the absence of a mechanical cause).

Upper Endoscopy

This test allows visualization of the mucosal surface of the esophagus, the stomach, and the duodenum. The presence and degree of esophagitis and the presence of an intraluminal mass can be determined, and biopsies taken.

Endoscopic Ultrasound

This test is used in patients with esophageal cancer to define the depth of penetration of the tumor through the esophageal wall (T) and the presence of enlarged periesophageal lymph nodes (N). Fine-needle aspiration of these nodes can be done, and cytologic analysis of the aspirate performed.

Esophageal Manometry

Esophageal manometry allows determination of: (1) LES location, length, pressure, and relaxation in response to swallowing; (2) pressure, duration, and velocity of propagation of the peristaltic waves; and (3) location, pressure, relaxation of the UES, and coordination with the pharyngeal contraction.

Ambulatory 24-Hour pH Monitoring

This test measures reflux of acid from the stomach into the esophagus, and it is considered the gold standard for the diagnosis of GERD. By convention, the catheter is placed 5 cm above the upper border of the manometrically determined LES and is kept in place for 24 hours, during which the patient does not alter the daily activities and diet. In addition to defining whether a pathologic amount of GER is present, the test establishes if there is a temporal correlation between episodes of reflux and symptoms (Figure 20–4). Esophageal impedance is a technique that measures flow of liquids and gas across the gastroesophageal junction, independently of the pH of the gastric refluxate. In association with pH monitoring, impedance is indicated in patients with proton pump inhibitors (PPIs)—resistant typical reflux symptoms and chronic unexplained cough.

Gastric Scintigraphy

It is indicated in patients who experience postprandial bloating and fullness to measure the gastric emptying of solids and liquids.

Computerized Axial Tomography

A computerized tomography (CT) scan is used to assess the presence of metastases (lung, liver, adrenals) in patients with esophageal cancer (M).

Positron Emission Tomography

A positron emission tomography (PET) scan is used to assess the metastatic spread of esophageal cancer (M). In addition, it might help predict the response of esophageal cancer to neoadjuvant therapy.

Laparoscopy/Thoracoscopy

Laparoscopy or thoracoscopy can be used to stage esophageal cancer, particularly when liver metastases or extensive lymphadenopathy are suspected.

The named primary esophageal motility disorders are achalasia, diffuse esophageal spasm, nutcracker esophagus, and the hypertensive LES. They occur in the absence of any other esophageal disorder such as reflux, and their cause is unknown. These disorders present with a combination of dysphagia, regurgitation, chest pain, and heartburn. Esophageal manometry is the key test that differentiates these disorders.

ACHALASIA

General Considerations

Esophageal achalasia is characterized by the absence of esophageal peristalsis. In most patients, the LES is hypertensive and fails to relax appropriately in response to swallowing. These abnormalities lead to impaired emptying of food with consequent stasis in the esophagus. The incidence of achalasia is about 1 in 100,000 persons. It affects men more than women, and it can occur at any age.

Pathogenesis

The etiology is still unknown, but two theories exist: (1) a degenerative disease of the neurons; and (2) infections of the neurons by a virus (eg, herpes zoster) or another infectious agent. The latter is supported by the fact that similar findings occur in patients with Chagas disease (American trypanosomiasis), a condition in which the infective organism destroys parasympathetic ganglion cells throughout the body, including the heart and the gastrointestinal, urinary, and respiratory tracts. The degeneration of the myenteric plexus of Auerbach determines loss of the postganglionic inhibitory neurons (which contain nitric oxide and vasoactive intestinal polypeptide), which mediate LES relaxation. Because the postganglionic cholinergic neurons are spared, there is unopposed cholinergic stimulation, which increases LES resting pressure and decreases LES relaxation. There is no propagation of peristaltic waves in response to swallowing, but rather the presence of simultaneous contractions.

Clinical Findings

A. Symptoms and Signs

Dysphagia is the most common symptom, experienced by about 95% of patients. It is often for both solids and liquids. Most patients adapt with changes in their diet and are able to maintain a stable weight, while others eventually experience some weight loss. Regurgitation of undigested food is the second-most common symptom and it is present in about 60% of patients. It occurs more often in the supine position and may lead to aspiration. Heartburn is present in about 40% of patients. It is not due to GER, but rather to stasis and fermentation of undigested food in the distal esophagus. Chest pain also occurs in about 40% of patients, due to esophageal distension, and it is usually experienced at the time of a meal.

B. Imaging Studies

Endoscopy is usually the first test performed to rule out a mechanical obstruction such as a peptic stricture or cancer. A barium swallow usually shows narrowing at the level of the gastroesophageal junction, and slow emptying of contrast (Figure 20–5). A dilated, sigmoid esophagus may be present in patients with longstanding achalasia.

C. Special Tests

Esophageal manometry is the gold standard for establishing the diagnosis of esophageal achalasia. The classic manometric findings are: (1) absence of esophageal peristalsis and (2) hypertensive LES (in about 50% of patients) that relaxes only partially in response to swallowing. When the esophagus is dilated and sigmoid in shape, it may be difficult to pass the catheter through the gastroesophageal junction into the stomach. In these cases, the catheter may be placed under fluoroscopic or endoscopic guidance. Recently, a new classification of esophageal achalasia has been proposed based on high-resolution manometry: type I, classic, with minimal esophageal pressurization; type II, achalasia with esophageal compression; and type III, achalasia with spasm.

Differential Diagnosis

Benign strictures due to GER and esophageal carcinoma may mimic the clinical presentation of achalasia. Sometimes an infiltrating tumor of the gastroesophageal junction can mimic not only the clinical and radiological presentation of achalasia but also the manometric profile. This condition, called secondary or pseudo-achalasia, should be suspected in patients older than 60 years with recent onset of dysphagia (< 6 months) and excessive weight loss. An endoscopic ultrasound or a CT scan with fine cuts is recommended to rule out an underlying malignancy.

Complications

Aspiration of retained and undigested food can cause repeated episodes of pneumonia. Achalasia is also a risk factor for esophageal squamous cell carcinoma, probably due to the continuous irritation of the mucosa by the retained and fermenting food. Adenocarcinoma can occur in patients who develop GER after either pneumatic dilation or myotomy.

Treatment

Therapy is palliative, and it is directed toward relief of symptoms by decreasing the outflow resistance caused by the dysfunctional LES. Because peristalsis is absent and does not return after any form of treatment, gravity becomes the key factor that allows emptying of food from the esophagus into the stomach.

Medical Therapy

Calcium-channel blockers are used to decrease LES pressure. However, because only 10% of patients benefit from this treatment, it should be used primarily in patients who have contraindications to either pneumatic dilation or to surgery.

A. Endoscopic Treatment

Intrasphincteric injection of botulinum toxin is used to block the release of acetylcholine at the level of the LES, thereby restoring the balance between excitatory and inhibitory neurotransmitters. This treatment, however, is of limited value. Only 60% of treated patients still have relief of dysphagia 6 months after treatment, and this number further decreases to 30% (even after multiple injections) 2.5 years later. In addition, it often causes an inflammatory reaction at the level of the gastroesophageal junction, which makes a subsequent myotomy more difficult. It should be used primarily in patients who are poor candidates for dilatation or surgery.

Pneumatic dilation of the LES is considered the most effective nonsurgical treatment of achalasia and has been the main modality of treatment for many years until the advent of minimally invasive surgery in the early 1990s. A balloon is inflated at the level of the gastroesophageal junction to rupture the muscle fibers while trying to leave the mucosa intact. The initial success rate is around 90%, but it decreases in most patients to 50% at 10 years, even after multiple dilations. The perforation rate is about 2%-5%. If a free perforation occurs, patients are taken emergently to the operating room, where closure of the perforation and a myotomy on the contralateral side of the esophagus are performed. The incidence of post-dilation GER is about 25%-35%. Patients who fail pneumatic dilation are usually treated by a laparoscopic Heller myotomy.

A recent novel approach to achalasia is the per-oral endoscopic esophageal myotomy (POEM). During this procedure the circular muscle fibers of the lower esophagus and the upper stomach are cut through a sub-mucosal tunnel. Long-term follow-up will be needed to assess the long-term results of this procedure.

B. Surgical Treatment

A laparoscopic Heller myotomy and partial fundoplication has progressively become the procedure of choice for esophageal achalasia during the last 20 years. The operation consists of a controlled section of the muscle fibers (myotomy) of the lower esophagus (6 cm) and proximal gastric wall (2-2.5 cm), followed by an anterior or a posterior partial fundoplication to prevent reflux. Patients spend 24-48 hours in the hospital, and return to regular activities in about 2 weeks. The operation effectively relieves symptoms in about 90% of patients, and it is effective even in patients who have a low LES pressure after previous dilation or when the esophagus is dilated. Therefore, it should be preferred to pneumatic dilation whenever surgical expertise is available. The incidence of postoperative reflux is around 25%-35%, and it is usually controlled by acid reducing medications. Persistent or recurrent dysphagia after myotomy can be treated with pneumatic dilation or another myotomy. Esophagectomy is reserved for patients with severe dysphagia who have failed both dilation and myotomy.

DIFFUSE ESOPHAGEAL SPASM

General Considerations

The cause of diffuse esophageal spasm is not known. Stress might play a role. Progression of diffuse esophageal spasm to achalasia has been documented.

Clinical Findings

A. Symptoms and Signs

The most common symptom is intermittent chest pain, which varies from slight discomfort to severe spasmodic pain that simulates the pain of coronary artery disease. Most patients complain of dysphagia, but weight loss is uncommon.

B. Imaging Studies

The barium swallow is abnormal in about 70% of patients. Fluoroscopic studies show segmental spasms, areas of narrowing, and irregular uncoordinated peristalsis (corkscrew esophagus) in about 30% of patients. An epiphrenic diverticulum is sometimes present.

C. Manometry

Esophageal manometry is the key test for establishing the diagnosis of diffuse esophageal spasm. The classic manometric findings are: (1) alternation of esophageal peristalsis and simultaneous contractions (> 10% and < 100%) and (2) normal LES function or abnormalities similar to those seen in achalasia.

D. Ambulatory 24-Hour pH Monitoring

This test is essential as the symptoms and the manometric picture of diffuse esophageal spasm can be caused by GERD. In such cases, treatment should be directed toward reflux because the dysmotility is secondary to the reflux. Therefore, it is crucial to be certain about the diagnosis, as treatment of GERD (acid-reducing medications or a fundoplication) is completely different from that of a primary esophageal motility disorder (pneumatic dilation or myotomy).

Differential Diagnosis

When chest pain is the predominant symptom, a complete cardiac workup is necessary to exclude a cardiac reason for the pain. Once the heart disease has been excluded, ambulatory pH monitoring must be performed to rule out abnormal GER, which is the most common cause of noncardiac chest pain. Esophageal manometry is the only test that distinguishes diffuse esophageal spasm from other primary esophageal motor disorders. An endoscopy should be performed to confirm the absence of intraluminal lesions.

Complications

Regurgitation and aspiration may occur, possibly leading to repeated episodes of pneumonia. An epiphrenic diverticulum may be present, secondary to the motor disorder.

Treatment

The therapeutic approach to diffuse esophageal spasm is similar to that of achalasia. Both disorders can be conceptualized as different points in a spectrum of esophageal motility, where peristalsis is progressively lost. In patients with diffuse esophageal spasm, dysphagia is secondary to abnormalities of the peristalsis and the LES, while the chest pain probably results from esophageal distension from poor emptying. Medical therapy (long-acting nitrates, calcium-channel blocking agents) is relatively ineffective. Pneumatic dilation improves the dysphagia in about 25% of patients. Intrasphincteric injection of botulinum toxin has also given poor results. In contrast, a laparoscopic Heller myotomy and partial fundoplication (as for patients with achalasia) improves both dysphagia and chest pain in about 80% of patients.

The hypertensive lower esophageal sphincter is a rare disorder that manifests with dysphagia and is characterized manometrically by a hypertensive LES (resting pressure > 45 mm Hg), which relaxes in response to swallowing, and normal esophageal peristalsis. Treatment is similar to that of esophageal achalasia.

NUTCRACKER ESOPHAGUS

General Considerations

The cause of this disorder is not known.

Clinical Findings

A. Symptoms and Signs

Chest pain is the most common symptom. Patients often come to the attention of gastroenterologists only after a thorough cardiac workup has been performed. About half of the patients complain of dysphagia in addition to chest pain.

B. Imaging Studies

The barium swallow is usually normal. An epiphrenic diverticulum is sometimes present.

C. Manometry

Esophageal manometry is the key test for establishing the diagnosis of nutcracker esophagus. The classic manometric findings are as follows: (1) normal propagation of the peristalsis waves (there are no simultaneous contractions)—the peristaltic waves in the distal esophagus, however, have very high amplitude (> 180 mm Hg) and duration (> 6 sec) and (2) normal LES function or abnormalities similar to those seen in achalasia and diffuse esophageal spasm.

D. Ambulatory 24-Hour pH Monitoring

This test is essential because the symptoms and the manometric picture of nutcracker esophagus can be caused by GERD. In such cases, treatment should be directed toward reflux because the dysmotility is secondary.

Differential Diagnosis

When chest pain is the predominant symptom, a complete cardiac work up is necessary to exclude a cardiac reason for the pain. Once the heart has been excluded as a cause of the symptom, ambulatory pH monitoring must be performed to rule out abnormal GER, which is the most common cause of noncardiac chest pain. Esophageal manometry is the only test that distinguishes nutcracker esophagus from other primary esophageal motility disorders.

Complications

Regurgitation and aspiration may occur, possibly leading to repeated pneumonic infections. An epiphrenic diverticulum may be present, secondary to the motor disorder.

Treatment

The nutcracker esophagus is not as well defined as the other primary esophageal motility disorders for both pathophysiology and treatment. Initially, it was thought that the high pressure of the peristaltic contractions was the cause of the chest pain, so treatment was aimed at decreasing the high amplitude of the peristaltic waves. However, calcium-channel blockers are unable to improve the chest pain even though they decrease the strength of the contractions. Similarly, the results of surgery have been disappointing, as chest pain persists after myotomy in about 50% of patients. Dysphagia is improved in 80% of patients.

ESOPHAGEAL DIVERTICULA

Esophageal diverticula are rare. They are located above the UES (pharyngoesophageal or Zenker diverticulum) or the LES (epiphrenic diverticulum). They are considered pulsion diverticula and are secondary to abnormalities of the sphincters in terms of resting pressure, relaxation in response to swallowing, and coordination with the segment above the sphincter. As a consequence, mucosa and submucosa protrude through the muscular layers, forming the outpouching.

1. Pharyngoesophageal Diverticulum (Zenker Diverticulum)

General Considerations

This is the most common of the esophageal diverticula and is three times more frequent in men than in women. Most patients are over age 60 years. The condition originates from the posterior wall of the esophagus, in a triangular area of weakness (Killian triangle), limited inferiorly by the upper border of the cricopharyngeal muscle and laterally by the oblique fibers of the inferior constrictor muscles of the pharynx. As the diverticulum enlarges, it tends to deviate from the midline, mostly to the left.

Pathogenesis

A Zenker diverticulum is due either to lack of coordination between the pharyngeal contraction and the opening time of the UES or to a hypertensive UES. Because of the increased intraluminal pressure, there is progressive herniation of mucosa and submucosa through the Killian triangle. Occasionally, UES dysfunction can occur in the absence of a diverticulum (cricopharyngeal achalasia). A hereditary syndrome called oculopharyngeal muscular dystrophy, consisting of ptosis and dysphagia, has been described in patients of French-Canadian ancestry. The dysphagia is the result of weak pharyngeal musculature in the face of normal UES function; it is considerably improved by UES myotomy. This syndrome also manifests with cervical dysphagia. A chronic cough may develop in some patients from aspiration of saliva and ingested food.

Clinical Findings

A. Symptoms

Dysphagia is the most common symptom and occurs in about 80%-90% of patients. Regurgitation of undigested food from the diverticulum often occurs, and can lead to aspiration into the tracheobronchial tree and pneumonia. Patients frequently have halitosis and can hear gurgling sounds in the neck. About 30% of patients have associated GERD.

B. Imaging Studies

A barium swallow clearly shows the position and size of the diverticulum or a prominent cricopharyngeal bar without diverticulum (Figure 20–6).

C. Special Tests

Esophageal manometry shows a lack of coordination between the pharynx and the cricopharyngeus muscle and often a hypertensive UES. In addition, it can show a hypotensive LES and abnormal esophageal peristalsis. Ambulatory pH monitoring determines if abnormal esophageal acid exposure is present. Endoscopy may be dangerous because the instrument can enter the diverticulum rather than the esophageal lumen and cause a perforation.

Differential Diagnosis

Differential diagnosis includes esophageal stricture, achalasia, and esophageal cancer.

Treatment

The standard treatment consists of eliminating the functional obstruction at the UES level (myotomy of the cricopharyngeus muscle and the upper 3 cm of the posterior esophageal wall) and excision or suspension of the diverticulum. For small diverticula (< 2 cm), the myotomy alone is sufficient. As an alternative to the conventional surgical treatment, a transoral endoscopic approach (using staplers, laser or coagulation through an endoscope that ablate the septum between the diverticulum and the cervical esophagus) can be used for diverticula between 3 and 6 cm in size. If present, GER should be corrected before dividing the UES in order to avoid aspiration. The prognosis is excellent in about 90% of cases. Complications are rare and the patients are usually able to eat the day after the procedure.

2. Epiphrenic Diverticulum

General Considerations

Epiphrenic diverticulum is located in the distal 10 cm of the esophagus. It is not a primary anatomic abnormality but rather the consequence of an underlying motility disorder of the esophagus that causes an outflow obstruction at the level of the gastroesophageal junction, with consequent increase in intraluminal pressure and progressive herniation of mucosa and submucosa through the esophageal muscle layers.

Clinical Findings

A. Symptoms

The symptoms experienced by the patient are in part due to the underlying motility disorder (dysphagia, chest pain) and in part due to the diverticulum per se (regurgitation with the risk of aspiration). Some diverticula, however, can be asymptomatic.

B. Imaging Studies

A chest radiograph can show an air-fluid level in the posterior mediastinum. A barium swallow clearly shows the position and size of the diverticulum (Figure 20–7). Endoscopy is important to rule out an esophageal malignancy.

C. Special Tests

In the majority of cases, esophageal manometry shows the underlying motility disorder. Sometimes it is difficult to position the manometry catheter, and endoscopic or fluoroscopic guidance might be necessary.

Differential Diagnosis

A paraesophageal hernia can be confused with an epiphrenic diverticulum. The barium swallow and the endoscopy help in establishing the diagnosis.

Treatment

The treatment is surgical, and the laparoscopic approach is preferred. It consists of: (1) resection of the diverticulum; (2) long myotomy—it is performed in the side of the esophagus opposite to where the diverticulum is located, it extends proximally to the upper border of the neck of the diverticulum and distally for about 2 cm onto the gastric wall; and (3) a partial fundoplication to prevent GER. A laparoscopic diverticulectomy, with myotomy and fundoplication, is successful in 80%-90% of cases.

ESOPHAGEAL MANIFESTATIONS IN SCLERODERMA & OTHER SYSTEMIC DISEASES

Scleroderma and several other systemic diseases may involve the esophagus. In scleroderma or progressive systemic sclerosis, there is involvement of the gastrointestinal tract in up to 90% of patients. The most common site of gastrointestinal involvement is the smooth muscle portion of the esophagus, where atrophy and fibrosis occur. The upper esophagus (striated muscle) and the UES are not involved. As a consequence, LES pressure is low and the peristalsis is weak (low amplitude or abnormal propagation of the peristaltic waves). These changes can be followed by an increased amount of GER with delayed clearance of the refluxed gastric contents. Esophageal symptoms usually appear in patients with the characteristic skin changes and Raynaud syndrome. In addition to heartburn and regurgitation, patients may have respiratory symptoms due to the upward extent of the gastric refluxate and aspiration. Dysphagia may be due to the abnormal peristalsis or to the presence of a peptic stricture. The diagnostic approach is similar to that of patients with GERD:

• A barium swallow may show a hiatal hernia or a stricture.

• Endoscopy shows esophagitis in 50%-60% of patients. Barrett esophagus (BE) is present in about 10% of patients.

• Esophageal manometry usually shows a hypotensive LES. Dysmotility is frequent and can progress to complete loss of peristalsis.

• Ambulatory pH monitoring is essential to establish the diagnosis. It can also measure the presence of acid in the proximal esophagus and pharynx in patients with cough or vocal cord problems.

• Gastric scintigraphy is indicated in patients who experience postprandial bloating and fullness to measure the gastric emptying of solids and liquids.

Similar esophageal changes may also occur in rheumatoid arthritis, Sjögren syndrome, Raynaud disease, and systemic lupus erythematosus. Similar motor abnormalities are occasionally seen in alcoholism, diabetes mellitus, myxedema, multiple sclerosis, and amyloidosis.

Medical management should always be tried first. A PPI is the drug of choice. If gastroparesis is present, a prokinetic medication such as metoclopramide should be added. A fundoplication should be considered particularly in patients with regurgitation, cough, or vocal cord problems.

GASTROESOPHAGEAL REFLUX DISEASE

General Considerations

GERD is the most common upper gastrointestinal disorder of the Western world and accounts for about 75% of esophageal diseases. Heartburn, usually considered synonymous with the presence of abnormal gastroesophageal reflux, is experienced by 20%-40% of the adult population of Western countries. However, because many symptomatic patients treat themselves with over-the-counter medications without consulting a physician, the prevalence of the disease is probably higher than reported. The incidence of reflux symptoms increases with age, and both sexes seem to be equally affected. Symptoms are more common during pregnancy, probably due to hormonal effects on the LES and the increased intra-abdominal pressure due to the enlarging uterus. Recent studies have demonstrated a link between obesity and GERD whereby the body mass index has a direct effect on the severity of reflux.

Pathogenesis

GERD is caused by the abnormal retrograde flow of gastric contents into the esophagus, resulting in symptoms and mucosal damage. A defective LES is the most common cause of GERD. Transient LES relaxations account for the majority of reflux episodes in patients without mucosal damage or with mild esophagitis, while a short and hypotensive LES is more frequently found in patients with more severe esophagitis. In 40%-60% of patients with GERD, abnormalities of esophageal peristalsis are also present. Because esophageal peristalsis is the main determinant of esophageal clearance (the ability of the esophagus to clear gastric contents refluxed through the LES), patients with abnormal esophageal peristalsis have more severe reflux and slower clearance. Therefore, these patients often have more severe mucosal injury and more frequent atypical symptoms such as cough or hoarseness. A hiatal hernia also contributes to the incompetence of the gastroesophageal junction by altering the anatomic relationship between the esophageal crus and the LES. As the gastroesophageal junction is displaced above the diaphragm, the pinchcock action of the esophageal crus is lost. In patients with large hiatal hernias, the LES is usually shorter and weaker, and the amount of reflux is greater.

Clinical Findings

A. Symptoms

Heartburn, regurgitation, and dysphagia are considered typical symptoms of GERD; however, a clinical diagnosis of GERD based on these symptoms is correct in only 70% of patients (when compared with the results of pH monitoring). A good response to therapy with PPIs is a good predictor of the presence of abnormal reflux. GERD can also cause atypical symptoms such as cough, wheezing, chest pain, hoarseness, and dental erosions. Two mechanisms have been postulated for GERD-induced respiratory symptoms: (1) a vagal reflex arc resulting in bronchoconstriction and (2) microaspiration into the tracheobronchial tree. Ear, nose, and throat symptoms such as hoarseness or dental erosions are instead secondary to the upward extent of the acid with direct damage of the vocal cords or teeth.

B. Barium Swallow

A barium swallow provides information about the presence and size of a hiatal hernia, the presence and length of a stricture, and the length of the esophagus. This test, however, is not diagnostic of GERD, as a hiatal hernia or reflux of barium can be present in the absence of abnormal reflux.

C. Endoscopy

Fifty percent of patients with abnormal reflux do not have esophagitis on endoscopy. Therefore, endoscopy is useful for diagnosing complications of GERD such as esophagitis, BE, or a stricture. In addition, there is major interobserver variation among endoscopists for the low grades of esophagitis (Table 20–2).

D. Esophageal Manometry

This test provides information about the LES (resting pressure, length, and relaxation) and the quality of esophageal peristalsis. In addition, manometry is essential for proper placement of the pH probe for ambulatory pH monitoring (5 cm above the upper border of the LES).

E. Ambulatory pH Monitoring

This test has a sensitivity and specificity of about 92% and is considered the gold standard for diagnosing GERD (Table 20–3). Medications that affect the production of acid by the parietal cells must be stopped 3 days (H₂-blocking agents) to 14 days (PPIs) prior to the study. Diet and exercise are unrestricted during the test in order to mimic a typical day of the patient’s life. This test should be performed: (1) in patients who do not respond to medical therapy, (2) in patients who relapse after discontinuation of medical therapy, (3) before antireflux surgery, or (4) when evaluating atypical symptoms such as cough, hoarseness, and chest pain. Because fewer than 50% of these patients with atypical symptoms experience heartburn or have esophagitis on endoscopy, a pH monitoring study becomes the only way to determine whether abnormal reflux is present, establishing a temporal link between episodes of reflux and symptoms. A pH probe with two sensors, located 5 and 20 cm above the LES, allows determination of the upward extent of the reflux. Tracings are analyzed for a temporal correlation between symptoms and episodes of reflux.

Differential Diagnosis

Heartburn can be the presenting symptom of irritable bowel syndrome, achalasia, cholelithiasis, coronary artery disease, or psychiatric disorders. Esophageal manometry and pH monitoring are essential to determine with certainty if GERD is present and if reflux is the cause of the symptoms.

Complications

Esophagitis is the most common complication. Peptic strictures are uncommon, particularly in the era of PPIs. BE is found in about 10%-15% of patients with reflux documented by pH monitoring. Some patients may eventually progress to high-grade dysplasia (HGD) and adenocarcinoma. Respiratory complications vary from chronic cough to asthma, aspiration pneumonia, and even pulmonary fibrosis. Vocal cord and dental damage can also occur.

Treatment

A. Lifestyle Modifications

Patients should eat frequent small meals during the day (to avoid gastric distention), avoiding fatty foods, spicy foods, and chocolate, as they lower LES pressure. The last meal should be no less than 2 hours before going to bed. In order to increase the effect of gravity, the head of the bed should be elevated over 4- to 6-inch blocks.

B. Medical Therapy

Antacids are useful for patients with mild intermittent heartburn. Acid-suppressing medications are the mainstay of medical therapy. H₂-blocking agents are usually prescribed for patients with mild symptoms or mild esophagitis. PPIs are superior to H₂-blocking agents because they determine a more profound control of the acid secretion, with healing of esophagitis in 80%-90% of patients. However, symptoms and esophagitis tend to recur in the majority of patients after discontinuation of therapy, so most patients need chronic maintenance therapy. In addition, about 50% of patients on maintenance PPIs require increasing doses to maintain healing of esophagitis. Acid-suppressing medications only alter the pH of the gastric refluxate, but reflux and aspiration can still occur because of an incompetent LES and ineffective esophageal peristalsis. Moreover, medical therapy is largely ineffective for the treatment of the extraesophageal manifestations of GERD due to the upward extension of the refluxate. PPIs can interfere with calcium absorption causing osteoporosis and fractures. In addition, PPIs can cause Clostridium difficile infection, delay in gastric emptying and abnormal cardiac activity due to decreased magnesium levels.

C. Surgical Therapy

The ideal patient for antireflux surgery is the one in whom ambulatory pH monitoring shows abnormal GER and whose heartburn is well controlled by PPIs. A careful selection of patients for surgery is mandatory. The operation is indicated in: (1) young patients who require chronic therapy with PPIs for control of symptoms, (2) patients in whom regurgitation persists during therapy, (3) patients with respiratory symptoms (cough, asthma, aspiration pneumonia, and pulmonary fibrosis), (4) patients with vocal cord damage, and (5) patients with BE. Recent evidence suggests that an effective antireflux operation may promote regression of the columnar epithelium in up to 50% of patients who have a short segment of BE (< 3 cm). In addition, it may arrest the progression from metaplasia to dysplasia. However, since the response to therapy is unpredictable, endoscopic surveillance after laparoscopic fundoplication in patients with BE is recommended.

The goal of surgical therapy is to restore the competence of the LES. A laparoscopic Nissen fundoplication (360°) is considered today the procedure of choice (Figure 20–8) because it increases the resting pressure and length of the LES, decreases the number of transient LES relaxations and improves quality of esophageal peristalsis. The operation is equally safe and effective in young and elderly patients.

The success of the operation is based on the following technical elements:

1. Dissection of the esophagus in the posterior mediastinum to allow 3-4 cm of esophagus to lie without tension below the diaphragm. By bringing the entire stomach and gastroesophageal junction below the diaphragm, a sliding hiatal hernia is reduced.

2. Division of the short gastric vessels in order to create a “floppy” fundoplication.

3. Approximation of the esophageal crus to decrease the size of the esophageal hiatus, thereby avoiding herniation of the wrap.

4. Construction of a 360° fundoplication over a 56-60 French bougie.

The hospital stay is short (usually 1-2 days), and the postoperative discomfort is minimal. Most patients return to work within 2-3 weeks. Control of symptoms is obtained in about 80%-90% of patients at 10 years after a fundoplication. Failures are treated with either medications or a second operation.

BARRETT ESOPHAGUS

General Considerations

BE is defined as a change in the esophageal mucosa with replacement of the squamous epithelium by columnar epithelium. About 10%-12% of patients undergoing endoscopy for symptoms of GERD are found to have BE, classified in short segment (< 3 cm in length) or long segment (3 cm or longer). Metaplasia may progress to high-grade dysplasia (HGD) and eventually adenocarcinoma. Thus, adenocarcinoma represents the final step of a sequence of events in which a benign disease (GERD) evolves into a preneoplastic disease and eventually into cancer.

Pathogenesis

BE is due to reflux of gastric contents (acid and duodenal juice) into the esophagus. When compared to patients with GERD with no mucosal injury or less severe esophagitis, patients with BE have a shorter and weaker LES and decreased amplitude of esophageal peristalsis. As a consequence, the amount of reflux is greater and esophageal clearance is slower. In addition, hiatal hernia is more common in patients with Barrett metaplasia.

Clinical Findings

A. Symptoms

Patients with BE typically have a long history of GERD. While most patients experience both typical and atypical symptoms of GERD, others may become asymptomatic over time due to the decreased sensitivity of the metaplastic epithelium.

B. Imaging Studies

Barium swallow may show ulcerations, a stricture, or a hiatal hernia. Endoscopy shows presence of “salmon pink” epithelium above the gastroesophageal junction, replacing the whitish squamous epithelium. The diagnosis is confirmed by pathologic examination of the esophageal mucosa and requires the identification of goblet cells, typical for intestinal epithelium.

C. Special Tests

Esophageal manometry often shows a short and hypotensive LES and abnormal esophageal peristalsis (decreased amplitude of peristaltic waves, simultaneous waves). Ambulatory pH monitoring usually shows a severe amount of acid reflux. Esophageal exposure to duodenal juice can be quantified by a fiberoptic probe that measures intraluminal bilirubin as a marker for duodenal reflux. In GERD patients, the prevalence of esophageal bilirubin exposure parallels the degree of mucosal injury, being higher in patients with BE. Nonacid reflux can be measured by impedance-pH monitoring.

Treatment

A. Barrett Esophagus: Metaplasia

The treatment options are similar to those of patients with GERD without metaplasia and consist of either PPIs or a fundoplication. A surgical approach might offer an advantage over medical therapy for the following reasons:

1. Successful elimination of reflux symptoms with PPIs does not guarantee control of an acid reflux. When pH monitoring is performed in asymptomatic BE patients treated with these medications, up to 80% of them still have abnormal acid reflux.

2. PPIs do not eliminate the reflux of bile, a major contributor to the pathogenesis of BE. In contrast, an antireflux operation prevents any form of reflux by restoring the competence of the gastroesophageal junction.

3. A fundoplication may promote regression of the columnar epithelium. Many studies have shown that regression occurs in 15%-50% of patients when the length of the BE segment is less than 3 cm. Regardless of the effect of the fundoplication on symptoms, surveillance endoscopy should be performed every 12-24 months.

B. Barrett Esophagus: Low-Grade Dysplasia

Patients with low-grade dysplasia (LGD) should be treated for 1-2 months with high doses of PPIs (3-4 pills/d), and subsequently the endoscopy should be repeated with multiple biopsies. The rationale for this approach is to decrease the mucosal inflammation by blocking acid secretion, allowing the pathologist a more accurate reading. If the repeated biopsies show metaplasia or HGD, the patient will be treated accordingly. If LGD is confirmed, the patient can continue taking acid-reducing medications or have a laparoscopic fundoplication with ablation of the dysplastic epithelium. Although there is evidence that regression to metaplasia or even disappearance of the columnar epithelium can occur after a successful fundoplication, endoscopic surveillance should be performed every 6-12 months, because of the higher risk of developing esophageal cancer in these patients compared to patients with non-dysplastic BE.

C. Barrett Esophagus: High-Grade Dysplasia

When HGD is found and confirmed by two experienced pathologists, two treatment options are available:

1. Patients can enroll in a program of strict endoscopic surveillance, with endoscopy performed every 3 months and 4-quadrant biopsies obtained for every centimeter of BE. The goal is to detect cancer as soon as it develops but before it becomes invasive and spreads to lymph nodes: the risk of lymph node metastasis is about 20%-30% in patients with submucosal invasive carcinoma (pT1b). Progression from HGD to cancer occurs in about 50% of patients 5 years after the initial diagnosis is established. This approach is reasonable if the patient is willing to undergo endoscopy every 3 months but unwilling to have an esophagectomy or if severe comorbidities are present.

2. For young and medically fit patients who are unwilling to undergo endoscopy every 3 months, an esophagectomy should be considered. The rationale for an operation is based on the following considerations: (a) cancer is already found in about 30% of patients thought to have HGD; (b) cancer develops in about 50% of patients during follow-up; (c) recent studies have shown that in specialized centers the operation can be performed with minimal morbidity and mortality, and postoperative quality of life similar to that of the general population; and (d) because the prognosis depends on the pathologic staging, waiting exposes patients to the risk of development of invasive cancer with lymph node metastases.

Esophagectomy remains the treatment of choice when: (1) endoscopic expertise is not available; (2) preoperative staging by endoscopic ultrasound is greater than T1aN0; (3) lymph node involvement is shown; (4) patients can not have a rigid follow-up; (5) multi focal dysplasia is present in a long segment; (6) complete eradication is not possible.

D. Endoscopic Treatment Modalities

Because either acid-reducing medications or a fundoplication determine regression in some patients with a short segment only, and because there is no evidence that they block progression to cancer, different modalities have been developed for the endoscopic treatment of the BE. Endoscopic resection is the basis of endoscopic therapy for BE and has been advocated not only as a therapeutic approach but also as a staging tool. The major advantage of the resection is the ability to provide samples of appropriate size and depth for an accurate histopathological diagnosis. Endoscopic Mucosal Resection (EMR) is curative in HGD and T1a lesions, with 5-year survival rates of 98%-100%.

Ablative therapies destroy the BE epithelium allowing replacement with neo-squamous epithelium. Photodynamic therapy is based on the administration of a photosensitizing drug, which is retained in the BE. Light of proper wavelength is then delivered endoscopically, producing an oxidative reaction with complete destruction of the abnormal mucosa in about 50% of patients. This technique, however, is associated with the development of esophageal strictures in about 30% of patients. In addition, islands of columnar epithelium can still be present under the regenerated squamous epithelium. The radio frequency ablation (RFA) seems to avoid these problems and is effective in about 70% of patients.

HIATAL HERNIA

General Considerations

Obesity, aging, and general weakening of the musculofascial structures set the stage for enlargement of the esophageal hiatus and herniation of the stomach into the posterior mediastinum. Hiatal hernias are divided into sliding hiatal hernias (type 1) (Figures 20–9 and 20–10) and paraesophageal hiatal hernias (types 2, 3, or 4) (Figures 20–11 and 20–12). The most common (95%) is the sliding hernia, where the gastroesophageal junction moves above the diaphragm together with some or the entire stomach. Type 2 hernias are characterized by herniation of the gastric fundus into the mediastinum alongside the esophagus, with the gastroesophageal junction remaining in an intra-abdominal position. Since the gastroesophageal sphincteric mechanism functions normally in most of these cases, reflux of gastric contents is uncommon. Type 3 hernias, also called mixed hernias, involve herniation of the stomach with the gastroesophageal junction into the mediastinum. In types 1 and 3, symptoms due to GER may occur along with symptoms secondary to the mechanical obstruction.

Finally, the rare type 4 hernias are characterized by an intrathoracic stomach along with associated viscera such as the spleen, colon, small bowel, or pancreas.

Clinical Findings

Small hiatal hernias are in most cases asymptomatic, while large hiatal hernias may cause a wide variety of symptoms such as epigastric discomfort, chest pain, postprandial bloating, dysphagia, or respiratory problems (asthma, cough, or dyspnea caused by chronic aspiration). Anemia is secondary to gastric erosions, and it can be the only presenting symptom. In addition, patients may experience symptoms due to GER.

Diagnosis

A barium swallow will delineate the anatomy and the type of hiatal hernia. Endoscopy is important to determine if gastric or esophageal inflammation is present and to rule out cancer. If reflux symptoms are present, manometry and pH monitoring should be performed.

Complications

The most frequent complications of paraesophageal hernia are hemorrhage, incarceration, obstruction, and strangulation. The herniated portion of the stomach often becomes congested, and bleeding occurs from erosions of the mucosa. Obstruction may occur, most often at the esophagogastric junction as a result of torsion and angulation at this point—especially if a large portion (or all) of the stomach herniates into the chest. In paraesophageal hiatal hernia—in contrast to the sliding type—other viscera such as the small and large intestines and spleen may also enter the mediastinum along with the stomach.

Treatment

Operative repair is indicated in symptomatic patients. The usual method is to return the herniated stomach below the diaphragm into the abdomen, repair the enlarged esophageal hiatus, and then add a fundoplication. In most cases, the operation can be performed laparoscopically. The results of surgical management are excellent in about 90% of patients.

TUMORS OF THE ESOPHAGUS

1. Benign Tumors of the Esophagus

General Considerations

Esophageal leiomyomas are the most common benign tumors of the esophagus. They represent 10% of all gastrointestinal leiomyomas. They originate in the smooth muscle layers, mostly in the lower two-thirds of the esophagus, and they narrow the esophageal lumen. These tumors consist of smooth muscle cells surrounded by a capsule of fibrous tissue. The mucosa overlying the tumor is generally intact, but occasionally it may become ulcerated as a result of pressure necrosis by an enlarging lesion. Leiomyomas are not associated with the development of cancer. Other tumors such as fibromas, lipomas, fibromyomas, and myxomas are rare. Congenital cysts or duplications of the esophagus (the second-most common benign lesion after leiomyomas) may occur at any level, although they are most common in the lower esophagus.

Clinical Findings

Many benign lesions are asymptomatic and are discovered incidentally during the upper gastrointestinal fluoroscopic examination. Benign tumors or cysts grow slowly and become symptomatic only after reaching a size of 5 cm or more. On barium swallow, leiomyomas appear as a smooth filling defect within the esophageal lumen (Figure 20–13). An intraluminal mass covered by normal mucosa can be easily recognized during endoscopy, but biopsies should not be taken because they may make subsequent enucleation of the tumor more difficult. Endoscopic ultrasound and chest CT help in the characterization of the tumor and in the differential diagnosis.

Differential Diagnosis

Leiomyomas, cysts, and duplications can be distinguished from cancer by their classic radiographic appearance. Intraluminal papillomas, polyps, or granulomas may be indistinguishable radiographically from early carcinoma, so their exact nature must be confirmed histologically.

Treatment

Small polypoid intraluminal lesions may be removed endoscopically. The treatment of choice for symptomatic leiomyomas is enucleation. While in the past a thoracotomy or a laparotomy was used, today enucleation can be accomplished by either a thoracoscopic or a laparoscopic approach.

2. Carcinoma of the Esophagus

General Considerations

The epidemiology of esophageal cancer in the United States has changed considerably during the last 30 years. In the 1970s, squamous cell carcinoma was the most common type of esophageal cancer, accounting for about 90% of the total cases. It was located in the thoracic esophagus and affected mostly black men. Over the past three decades, there has been a progressive increase in the incidence of adenocarcinoma of the distal esophagus and gastroesophageal junction, so that today it accounts for more than 70% of all new cases of esophageal cancer. It is more frequent in white men with GERD and it is linked to BE.

Pathogenesis

The most common contributing factors for squamous cell carcinoma are cigarette smoking and chronic alcohol exposure. Chronic ingestion of hot liquids or foods, poor oral hygiene, and nutritional deficiencies may play a role. Certain medical conditions such as achalasia, caustic injuries of the esophagus, and Plummer–Vinson syndrome are associated with an increased incidence of squamous cell cancer. GERD is the most common predisposing factor for adenocarcinoma of the esophagus, where adenocarcinoma represents the last event of a sequence that starts with GERD and progresses to metaplasia, HGD, and cancer. Esophageal cancer arises in the mucosa and subsequently invades the submucosa and the muscle layers. Ultimately, structures located next to the esophagus may be infiltrated (tracheobronchial tree, aorta, recurrent laryngeal nerve). At the same time, the tumor tends to metastasize to the lymph nodes (mediastinal, celiac, cervical) and to the liver, lungs, peritoneum, adrenals, and bones.

Clinical Findings

A. Symptoms

Early esophageal cancer may be asymptomatic. As the cancer grows, dysphagia is the most common symptom. It is initially for solids but eventually it progresses to liquids. Weight loss occurs in more than 50% of patients. Patients can have pain when swallowing. Pain over bony structures may be due to metastases. Hoarseness is usually due to invasion of the right or left recurrent laryngeal nerves with paralysis of the ipsilateral vocal cord. Respiratory symptoms may be due to regurgitation and aspiration of undigested food or to invasion of the tracheobronchial tree, with development of a tracheoesophageal fistula.

B. Imaging Studies

Barium swallow shows the location and the extent of the tumor. Esophageal cancer usually presents as an irregular intraluminal mass or a stricture (Figure 20–14). Endoscopy allows direct visualization and biopsies of the tumor. For tumors of the upper and midesophagus, bronchoscopy is indicated to rule out invasion of the tracheobronchial tree.

C. Special Tests

After the diagnosis is established, it is important to determine the staging of the cancer (Table 20–4). Abdominal and chest CT scans and PET are useful to detect distant metastases and invasion of structures next to the esophagus. Endoscopic ultrasound is the most sensitive test to determine the depth of penetration by the tumor, the presence of enlarged periesophageal lymph nodes, and invasion of structures next to the esophagus. Furthermore, it allows a fine-needle aspiration of enlarged periesophageal lymph nodes. A bone scan is indicated in patients with new onset of bone pain.

Differential Diagnosis

The differential diagnosis includes peptic strictures due to reflux, achalasia, and benign esophageal tumors.

Treatment

Treatment is based on the stage of the cancer. In patients with early esophageal cancer (pT1a), an esophagectomy can be avoided, because of the very low risk of lymph nodes metastasis (0%-3%), and EMR and RFA are very effective. However, patients need to undergo a very strict endoscopic follow-up to detect possible early recurrence.

Patients with invasive esophageal cancer (T1b and T2) are considered candidates for esophagectomy if the following criteria are met: (1) no evidence of spread of the tumor to structures next to the esophagus such as the tracheobronchial tree, the aorta, or the recurrent laryngeal nerve; (2) no evidence of distant metastases; (3) the patient is fit from a cardiac and respiratory point of view. An esophagectomy can be performed by using an abdominal and a cervical incision (with blunt dissection of the thoracic esophagus through the esophageal hiatus; transhiatal esophagectomy) or by using an abdominal and a right chest incision (transthoracic esophagectomy). After removal of the esophagus, continuity of the gastrointestinal tract is reestablished by using either the stomach or the colon. The transhiatal esophagectomy offers the advantage of avoiding the chest incision, with decreased compromise of lung function and decreased postoperative discomfort. The validity of the trans-hiatal esophagectomy as a cancer operation was initially questioned because part of the operation is not done under direct vision and because of the small number of resected lymph nodes. However, many retrospective studies and prospective randomized trials have shown no difference in survival between the two operations, suggesting that it is not the type of operation that influences survival but rather the stage of the disease at the time the operation is performed. The morbidity rate of the operation is around 30%, and it is mostly due to cardiac (arrhythmias), respiratory (atelectasis, pleural effusion), and septic complications (anastomotic leak, pneumonia). The mortality rate in specialized and “high volume” centers is less than 5%. These results are due to the presence of an experienced team composed of surgeons, anesthesiologists, intensivists, cardiologists, radiologists, and nurses.

The best treatment for patients with locally advanced cancer (T3-4N0-3, T2-N1-3) includes a combination of radiotherapy and chemotherapy used in order to improve local (radiotherapy) and distant control of the disease (chemotherapy), followed by surgery. Overall, it seems that the combination of neoadjuvant therapy followed by surgery offers the best survival benefit. This is particularly true in the subgroup of patients (about 20%) who have a “complete pathologic response” (no tumor found in the specimen).

Nonoperative therapy is reserved for patients who are not candidates for surgery because of local invasion of the tumor, metastases, or a poor functional status. The goal of therapy in these patients is palliation of the dysphagia. The following treatment modalities are available to achieve this goal:

1. Expandable, coated, metallic stents can be deployed by endoscopy under fluoroscopic guidance in order to keep the esophageal lumen open. They are particularly useful when a tracheoesophageal fistula is present.

2. Laser therapy (Nd:YAG laser) relieves dysphagia in up to 70% of patients. However, multiple sessions are usually required to keep the esophageal lumen open.

3. Radiation therapy is successful in relieving dysphagia in about 50% of patients.

The stage of the disease is the most important prognostic factor. Overall 5-year survival for esophageal cancer remains around 25%.

OTHER SURGICAL DISORDERS OF THE ESOPHAGUS

PERFORATION OF THE ESOPHAGUS

General Considerations

Esophageal perforations can result from iatrogenic instrumentation (eg, endoscopy, balloon dilation), severe vomiting, external trauma, and other rare causes. The subsequent clinical manifestations are influenced by the site of the perforation (ie, cervical or thoracic) and, in the case of thoracic perforations, whether or not the mediastinal pleura has been ruptured. Morbidity resulting from esophageal perforation is principally due to infection. Immediately after injury, the tissues are contaminated by esophageal contents, but infection has not become established; surgical closure of the defect will usually prevent the development of serious infection. If more than 24 hours have elapsed since the time of injury, severe contamination has occurred. At this time, the esophageal defect usually breaks down if it is surgically closed, and measures to treat mediastinitis and empyema may not be adequate to avoid a fatal outcome. Although serious infection usually occurs if surgical repair is delayed, a few cases of minor instrumental perforations can be managed by antibiotics without operation.

A. Instrumental Perforations

Medical instrumentation is the most common cause of esophageal perforation (diagnostic or therapeutic endoscopy). Instrumental perforations are most likely to occur in the cervical esophagus. The endoscope may press the posterior wall of the esophagus against osteoarthritic spurs of the cervical vertebrae, causing contusion or laceration. The cricopharyngeal area is the most common site of injury. Perforations of the thoracic esophagus may occur at any level but are most common at the natural sites of narrowing, at the level of the left main stem bronchus and at the diaphragmatic hiatus. Perforations during pneumatic dilatation for achalasia (2%-6%) occur proximal to the gastroesophageal junction.

B. Spontaneous (Postemetic) Perforation (Boerhaave Syndrome)

Spontaneous perforation usually occurs in the absence of preexisting esophageal disease, but 10% of patients have reflux esophagitis, esophageal diverticulum, or carcinoma. Most cases follow a bout of heavy eating and drinking. The perforation most frequently occurs in the left posterolateral wall, 3-5 cm above the gastroesophageal junction. The tear results from excessive intraluminal pressure, usually caused by violent retching and vomiting. Some cases have also been associated with childbirth, defecation, convulsions, heavy lifting, and forceful swallowing. The overlying pleura are also torn, so both the mediastinum and the pleural cavity are contaminated with esophageal contents. The second-most common site of perforation is at the midthoracic esophagus, on the right side at the level of the azygous vein.

Clinical Findings

A. Signs and Symptoms

The principal early manifestation is pain, which is felt in the neck with cervical perforations and in the chest or upper abdomen with perforations of the thoracic esophagus. The pain may radiate to the back. With cervical perforations, pain is followed by crepitus in the neck, dysphagia, and signs of infection. Perforations of the thoracic esophagus, which communicate with the pleural cavity in about 75% of cases, are usually accompanied by tachycardia, tachypnea, dyspnea, and the early development of hypotension. With perforation into the chest, pneumothorax is produced, followed by hydrothorax and, if not promptly treated, empyema. The left chest is involved in 70% and the right chest in 20%; involvement is bilateral in 10%. Escape of air into the mediastinum may result in a “mediastinal crunch,” which is produced by the heart beating against air-filled tissues (Hamman sign). If the pleura remain intact, mediastinal emphysema appears more rapidly, and pleural effusion is slow to develop.

B. Imaging Studies

X-ray studies are important to demonstrate that perforation has occurred and to locate the site of the injury. In perforations of the cervical esophagus, x-rays show air in the soft tissues, especially along the cervical spine. The trachea may be displaced anteriorly by air and fluid. Later, widening of the superior mediastinum may be seen. With thoracic perforations, mediastinal widening and pleural effusion with or without pneumothorax are the usual findings. An esophagogram using water-soluble contrast medium should be performed promptly in every patient suspected of having an esophageal perforation (Figure 20–15). If a leak is not seen, the examination should be repeated using barium. A CT scan of the chest is also useful to localize the perforation and eventually to drain mediastinal fluid collections.

C. Special Studies

Thoracentesis will reveal cloudy or purulent fluid, depending on how much time has passed since the time of perforation. The amylase content of the fluid is elevated, and serum amylase levels may also be high as a result of absorption of amylase from the pleural cavity.

Treatment

Broad-spectrum antibiotics should be given immediately. The infection is usually polymicrobial with Staphylococcus, Streptococcus, Pseudomonas, and Bacteroides. Early operation is appropriate for all but a few cases, and every effort should be made to operate before the perforation is 24 hours old. For lesions treated within this time limit, the operation should consist of closure of the perforation and external drainage. External drainage alone may suffice for small cervical perforations, which may be difficult to find. Patients with achalasia in whom perforation has resulted from balloon dilation should have the tear in the esophagus repaired and a Heller myotomy performed on the opposite side of the esophagus. Definitive therapy (eg, resection) should also be performed in patients with other surgical conditions, such as esophageal carcinoma.

Primary repair has a high failure rate if the perforation is older than 24 hours. The classic recommendation in this situation has been to isolate the perforation (ie, to minimize further contamination) by performing a temporary cervical esophagostomy, ligating the esophagus just proximal to the gastroesophageal junction, and placing a feeding jejunostomy for enteral nutrition. Alternatively, the segment of esophagus where the perforation is located can be resected, bringing the proximal end of esophagus out through the neck and closing the distal end. The mediastinum is drained, and a feeding jejunostomy is created. Later, the esophagostomy is taken down, and stomach or colon interposed to bridge the gap. Blunt esophagectomy may be feasible as emergency treatment of instrumental perforation in a patient with lye stricture.

Nonoperative management consisting of antibiotics alone may be all that is necessary in a few selected cases of instrumental perforation. This approach should be confined to patients without thoracic involvement (eg, pneumothorax or hydrothorax) whose esophagogram demonstrates just a short extraluminal sinus tract without wide mediastinal spread (ie, the contamination is limited) and who have no systemic signs of sepsis (eg, hypotension and tachypnea). Recently, esophageal stents have been placed for the treatment of iatrogenic, intrathoracic esophageal perforations.

The survival rate is 90% when surgical treatment is accomplished within 24 hours. The rate drops to about 50% when treatment is delayed.

INGESTED FOREIGN OBJECTS

Most cases of ingested foreign objects occur in children who swallow coins or other small objects. In adults, the problem most often consists of esophageal meat impaction or, less commonly, lodged bones or toothpicks. Dentures and esophageal disease, such as a benign stricture, are the principal predisposing factors in adults. Prisoners and mentally ill persons occasionally swallow foreign objects intentionally.

About 90% of swallowed foreign objects pass into the stomach and from there into the intestine and are eventually passed without problems. Ten percent hang up in the esophagus. If they traverse the esophagus, objects whose dimensions exceed 2-5 cm tend to remain in the stomach. Ten percent of ingested foreign objects require endoscopic removal, and 1% requires surgery. About 10% of ingested foreign objects enter the tracheobronchial tree.

The patient’s history usually defines the problem adequately. The patient with a foreign object in the esophagus may or may not experience dysphagia or chest pain.

Specific Kinds of Ingested Foreign Objects

A. Coins

Pennies and dimes usually pass into the stomach, but larger coins will lodge in the esophagus at or just beyond the cricopharyngeus. It is important to know if a swallowed coin has remained in the esophagus, and whether or not the patient has symptoms is an unreliable basis for making the determination. Therefore, anteroposterior and lateral chest x-rays should be obtained to determine whether the coin is in the esophagus or trachea. Small children should be x-rayed from the base of the skull to the anus in order to find any additional coins in the gut.

Coins in the esophagus should be removed promptly, since complications may occur if treatment delay exceeds 24 hours. The procedure is best accomplished with a grasping forceps passed through a flexible endoscope. Sedation is adequate for older children or adults, but general endotracheal anesthesia is required in order to protect the airway of infants and young children. A smooth foreign body too large to grasp with a forceps can be removed by passing a dilating balloon beyond it and then withdrawing the endoscope and balloon as a unit. If the object is small enough (< 20 mm), it may be pushed into the stomach.

Once a coin has passed into the stomach, it can be observed by periodic x-rays for as long as a month before the conclusion is reached that spontaneous elimination is unlikely and endoscopic removal is indicated.

B. Meat Impaction

Meat is the most common foreign object that lodges in the esophagus of adults, and many affected patients have underlying esophageal disease. The site of meat impaction is usually at the cricopharyngeus muscle or in the distal esophagus in patients with achalasia, diffuse esophageal spasm, or a stricture.

No x-rays (especially barium studies) are indicated, for they make the endoscopist’s task more difficult. If obstruction is complete and the patient cannot handle saliva, endoscopy should be performed as an emergency to prevent aspiration. If the clinical findings are minor, however, endoscopy can be postponed for up to 12 hours to see whether the food will pass spontaneously.

Meat can usually be removed as a single piece using a polypectomy snare passed through a flexible endoscope. In some cases, a meat bolus can be pushed into the stomach, which is safe so long as it passes with minimal pressure. After the esophagus has been cleared, it should be checked endoscopically for underlying disease. An esophageal stricture should be dilated if the esophageal wall is not acutely inflamed as a result of the meat impaction.

C. Sharp and Pointed Objects

Bones, safety pins, hat pins, razor blades, toothpicks, nails, and many others constitute this group of foreign objects. The general principles of management are: (1) to remove these objects endoscopically by grasping and pulling a blunt side (eg, the hinge of an open safety pin) with forceps, (2) to remove a piece of glass or a razor blade by pulling it into the lumen of a rigid esophagoscope, or (3) to operate if neither of these methods appears to be safe. Sharp or pointed objects in the stomach should be removed surgically, since 25% of them will perforate the intestine, usually near the ileocecal valve, if they exit the pylorus.

D. Button Batteries

These small batteries are swallowed by children, just like coins, but unlike coins, they are highly corrosive and should be removed urgently before a serious complication such as an esophagotracheal or esophagoaortic fistula develops.

E. Cocaine Packets

Cocaine smugglers may swallow small packets of cocaine in balloons or condoms. Rupture of just one of these packets can be fatal, so attempts at endoscopic removal are unsafe. If it appears that the packets will pass spontaneously, the patient may be watched; otherwise, surgical removal is indicated.

CAUSTIC INJURIES OF THE ESOPHAGUS

General Considerations

Ingestion of strong solutions of acid or alkali or of solid substances of similar nature produces extensive chemical burns. The injury usually represents a suicide attempt in adults and accidental ingestion in children. Strong alkali produces “liquefaction necrosis,” which involves dissolution of protein and collagen, saponification of fats, dehydration of tissues, thrombosis of blood vessels, and deep penetrating injuries. Acids produce a “coagulation necrosis” involving eschar formation, which tends to shield the deeper tissues from injury. Depending on the concentration and the length of time the irritant remains in contact with the mucosa, sloughing of the mucous membrane, edema and inflammation of the submucosa, infection, perforation, and mediastinitis may develop.

Ingested lye in solid form tends to adhere to the mucosa of the pharynx and proximal esophagus. Severe acute esophageal necrosis is rare, and the main clinical problems are early edema and late stricture formation, principally of the proximal esophagus. Liquid caustics commonly produce much more extensive esophageal necrosis, and occasionally even tracheoesophageal and esophagoaortic fistulas. If the patient survives the acute phase, a lengthy nondilatable stricture often develops.

Ingestion of strong acid characteristically produces greatest injury to the stomach, with the esophagus remaining intact in over 80% of cases. The result may be immediate gastric necrosis or late antral stenosis.

Nearly all severe injuries are caused by strong alkali. Weak alkali and acid are associated with less extensive lesions.

Clinical Findings

A. Symptoms and Signs

Systemic symptoms roughly parallel the severity of the caustic burn. The most common finding is inflammatory edema of the lips, mouth, tongue, and oropharynx; in the absence of visible injury in this area, severe esophageal damage is rare. Patients with serious esophageal burns often experience chest pain and dysphagia and drooling of large amounts of saliva. Pain on swallowing may be intense. If the damage is severe, the patient often appears toxic, with high fever, prostration, and shock. The absence of toxicity does not rule out severe injury. Tracheobronchitis accompanied by coughing and increased bronchial secretions is frequently noted. Stridor may be present, and in a few patients respiratory obstruction progresses rapidly and requires tracheostomy for relief. Complete esophageal obstruction due to edema, inflammation, and mucosal sloughing may develop within the first few days.

B. Esophagoscopy

Endoscopy is the key test in the evaluation of caustic trauma to the esophagus. Determination of the extent of injury by esophagoscopy contributes substantially to therapeutic decisions. Endoscopy should be performed after the initial resuscitation, usually within 24 hours of admission. The scope is inserted far enough to gauge the most serious degree of burn, which is classified as first-, second-, or third-degree, as defined in Table 20–5.

C. Radiology

A chest x-ray should be taken in all patients. It may show signs of esophageal perforation (subcutaneous emphysema, pneumomediastinum, pneumothorax) or aspiration (pulmonary infiltrates). An esophagogram is indicated in the initial evaluation if perforation is suspected and in later stages to detect the presence of a stricture.

Treatment

Patients should be hospitalized and intravenous fluids antibiotics should be administered. The use of steroids is still controversial. A nasogastric tube placed under fluoroscopic or endoscopic guidance allows stenting of the esophagus, preventing complete obstruction of the lumen.

Patients with first-degree burns do not require aggressive therapy and may be discharged from the hospital after a short period of observation. Second-degree and minor spotty third-degree injuries are treated by inserting a nasogastric tube. Nutrition can be given through the nasogastric tube or parenterally. Periodic esophagograms are obtained in follow-up to look for stricture formation, which is treated early in its development by dilations and eventually resection.

Third-degree burns involving extensive esophagogastric necrosis require emergency esophagogastrectomy, esophagostomy, and feeding jejunostomy. Esophagectomy is best performed by the blunt technique using a laparotomy and cervical incision. It is sometimes necessary to resect adjacent organs (eg, transverse colon) that have also been damaged. Reconstruction by substernal colon interposition is performed 8-12 weeks later.

Early and proper management of caustic burns provides satisfactory results in most cases. The ingestion of strong acid or alkaline solutions with extensive immediate destruction of the mucosa produces profound pathologic changes that may result in fibrous strictures that require dilations and, in some cases, esophagectomy and colon interposition.

ESOPHAGEAL BANDS, WEBS, OR RINGS

A narrow mucosal ring (Schatzki ring) may develop at the lower end of the esophagus. Most patients are relatively free from symptoms. Dysphagia occurs when the ring is less than 12 mm in diameter. In most cases, the ring is located at the squamocolumnar junction and occurs in a patient with GERD. Being confined to the mucosa, it differs from an inflammatory (peptic) stricture, which involves all layers of the esophagus. A barium swallow clearly identifies the problem. Treatment consists of endoscopic dilation of the ring and treatment of the associated reflux (acid-reducing medications or fundoplication).

The diaphragm (Figure 20–16) is a musculotendinous, dome-shaped structure attached posteriorly to the first, second, and third lumbar vertebrae, anteriorly to the lower sternum and laterally to the costal arches. It separates the abdominal and the thoracic cavities. The diaphragm allows the passage of various normal structures through anatomic foramina. The aortic hiatus lies posteriorly at the level of the twelfth thoracic vertebra, and through it pass the aorta, the thoracic duct, and the azygos venous system. The esophageal hiatus lies immediately anteriorly and slightly to the left at the level of the tenth thoracic vertebra and is separated from the aortic hiatus by the decussation of the right crus of the diaphragm. Through this hiatus pass the esophagus and the vagus nerves. At the level of the ninth thoracic vertebra and slightly to the right of the esophageal hiatus is the vena caval foramen, which allows passage of the inferior vena cava and small branches of the phrenic nerve. The phrenic arteries arising directly from the aorta supply the diaphragm along with the lower intercostal arteries and the terminal branches of the internal mammary arteries.

PARASTERNAL OR RETROSTERNAL (FORAMEN OF MORGAGNI) HERNIA & PLEUROPERITONEAL (FORAMEN OF BOCHDALEK) HERNIA

Failure of fusion of the sternal and costal portions of the diaphragm anteriorly in the midline creates a defect (foramen of Morgagni) through which hernias can occur. Normally, the diaphragm becomes fused, allowing only the internal mammary arteries and their superior epigastric branches, along with lymphatics, to pass through this area. Posterolaterally, failure of fusion of the pleuroperitoneal canal creates a defect through which viscera may herniate to produce a foramen of Bochdalek hernia (Figure 20–17).

Although both types of hernia are congenital, symptoms in the Morgagni hernia usually do not develop until middle life or later. This type of hernia is more frequent in women. These hernias are mostly right-sided and have a hernia sac. The most common contents are the omentum, the colon, and the stomach. On the other hand, the Bochdalek hernia occurs more frequently on the left side and may cause severe respiratory distress at birth, requiring an emergent operation. Routine chest films show a retrosternal solid mass, a retrosternal air-filled viscus, or similar findings in the posterolateral thorax if a Bochdalek hernia is present. Chest CT confirms the diagnosis and identifies the contents of the hernia.

Elective surgical repair is indicated in most instances to prevent complications. An emergent operation may become necessary in the newborn infant who develops progressive cardiorespiratory insufficiency. Repair of the defect by a transabdominal approach is preferable, and the results are excellent. A minimally invasive approach (laparoscopic or thoracoscopic) has been recently used.

TRAUMATIC DIAPHRAGMATIC HERNIA

Traumatic rupture of the diaphragm may occur as a result of penetrating wounds or severe blunt external trauma. Lacerations usually occur in the tendinous portion of the diaphragm, most often on the left side. The liver provides protection to diaphragmatic injury on the right side except from penetrating wounds. Abdominal viscera may immediately herniate through the defect in the diaphragm into the pleural cavity or may gradually insinuate themselves into the thorax over a period of months or years.

Clinical Findings

Diaphragmatic ruptures present in two ways. In the acute form, the patient has recently experienced blunt trauma or a penetrating wound to the chest, abdomen, or back. The clinical manifestations are essentially those of the associated injuries, but occasionally, massive herniation of abdominal viscera through the diaphragm causes respiratory insufficiency. In the chronic form, the diaphragmatic tear is unrecognized at the time of the original injury. Sometime later, symptoms (eg, pain, bowel obstruction) appear from herniation of viscera. Respiratory symptoms in such cases are less common.

Plain films of the chest may show a radiopaque area and occasionally an air-fluid level if hollow viscera have herniated. If the stomach has entered the chest, the abnormal path of a nasogastric tube may be diagnostic. Ultrasonography, CT scan, and MRI may demonstrate the diaphragmatic rent. Barium study of the colon may show irregular patches of barium in the colon above the diaphragm or a smooth colonic outline if the colon does not contain feces.

Differential Diagnosis

Traumatic rupture of the diaphragm must be differentiated from atelectasis, space-consuming tumors of the lower pleural space, pleural effusion, and intestinal obstruction due to other causes.

Complications

Hemorrhage and obstruction may occur. If herniation is massive, progressive cardiorespiratory insufficiency may threaten life. The most severe complication is strangulating obstruction of the herniated viscera.

Treatment

For acute ruptures, a transabdominal (most commonly) or transthoracic route is used depending on the procedure required to treat ancillary injuries. When the diaphragmatic tear is the only injury, it is usually fixed by laparotomy. Chronic injuries can be repaired by either approach. Asymptomatic tears of the diaphragm with herniated viscera should be repaired, because the risk of strangulating obstruction is high. Laparoscopy is very useful for both diagnosis and treatment. Surgical repair of the rent in the diaphragm is curative, and the prognosis is excellent. The diaphragm supports sutures well, so recurrence is practically unknown.

TUMORS OF THE DIAPHRAGM

Primary tumors of the diaphragm are not common. The majority are benign lipomas. Pericardial cysts develop in the space between the heart and the diaphragm and are usually unilocular and on the right side. Fibrosarcoma, the most common primary malignant diaphragmatic tumor, is extremely rare.

Benign tumors are usually asymptomatic. Since their benign nature cannot be established except by histology, all lesions of this type should be excised through an appropriate thoracotomy or thoracoabdominal approach.