Esophageal cancer is the eighth most common cancer diagnosis worldwide and remains a leading cause of cancer death in both highly developed and economically underdeveloped countries. In the United States, the incidence rate (4.2 new cases per 100,000 person-years) and death rate (4.1 deaths per 100,000 person-years) for esophageal cancer are nearly identical, indicative of the aggressive nature of the disease and the advanced stage at which most patients present.1–3 Indeed, based on data from the Surveillance, Epidemiology, and End Results (SEER) Database, the 5-year overall survival rate for all esophageal cancer is a mere 18.8%, and 39% of patients have distant metastasis at the time of diagnosis.3 These statistics highlight the need to optimize the care of these patients through a thorough understanding of the anatomy, pathophysiology, staging, and treatment of esophageal cancer.
The esophagus is approximately 25 cm long, extending from the pharynx to the stomach through the posterior mediastinum. It is a muscular conduit composed of four layers: mucosa, submucosa, muscularis propria, and adventitia (Fig. 10-1). Anchored to the cricoid cartilage cranially and the diaphragm caudally, the esophagus is divided into three clinical portions: cervical, thoracic, and abdominal. Each division has its own unique arterial supply and venous drainage (Fig. 10-2).
The four layers of the esophagus: mucosa, submucosa or lamina propria, muscularis propria, and adventitia.
Arterial blood supply of the esophagus.
The cervical portion of the esophagus is approximately 5 cm in length and extends from the hypopharynx (near the sixth cervical vertebra) to the thoracic inlet (at the level of the sternal notch). At its origin, the esophagus begins in the midline and then deviates to the left in the lower neck. The arterial supply to the cervical esophagus is derived from branches of the inferior thyroid arteries as well as smaller accessory branches from surrounding arteries. The venous system parallels the arterial system; most of the venous drainage of the cervical esophagus is to the inferior thyroid veins. The first of three physiologic narrowings of the esophagus is in the cervical region—the cricopharyngeus (upper esophageal sphincter), which is located approximately 12 to 15 cm from the incisors and is the narrowest point in the gastrointestinal tract.
The thoracic portion of the esophagus is approximately 20 cm long and extends from the thoracic inlet to the diaphragm (around the 10th thoracic vertebra). As it courses through the posterior mediastinum, the esophagus is located on the left in the upper thorax, descends between the left mainstem bronchus and the aortic arch to return to midline in the midchest, and passes to the left at the level of the inferior pulmonary veins. The ...