Skip to Main Content


Malignant and Benign Lesions


  • • Divided into 3 regions

    • -Anterior

      -Middle (great vessels, heart, trachea, and esophagus)


    • Neurogenic tumors most common masses in children (50-60%);

    • -In children younger than 4 years, masses are invariably malignant (neuroblastomas)

    • Neurogenic tumors most common mediastinal mass in adults

    • -Posterior compartment typical

      -Well circumscribed, calcified, benign

    • Anterior masses:

    • -More often malignant than neurogenic tumors

      -Thymoma most common then lymphoma


Neurogenic Tumors


  • • Posterior mediastinum, often superiorly from intercostal or sympathetic nerves

    • Nerve sheath tumors (eg, schwannoma and neurofibroma) most common (40-65%)

    • Usually benign, 10% malignant

    • Malignant tumors arise from nerve cells (neuroblastoma); more common in children

    • May be multiple or dumbbell shape


Mediastinal Cystic Lesions


  • • Arise from pericardium, bronchi, esophagus, or thymus

    • 75% located near cardiophrenic angles, 75% on right side

    • 10% are diverticula of pericardial sac that communicate with pericardial space

    • Bronchogenic cysts arise below carina

    • Enterogenous cysts arise along esophagus, may be incorporated, and associated with vertebral anomalies

    • 10% nonspecific without identifiable lining


Germ Cell Tumors


  • • Common in anterior mediastinum

    • Both solid and cystic, may contain teeth or hair

    • Ectodermal, endodermal, mesodermal elements present

    • Most metastatic from retroperitoneal disease; < 5% are primary tumors

    • Seminoma (40%), embryonal carcinomas and nongestational choriocarcinomas (20%), yolk sac (20%), and teratomas (20%) can have both benign and malignant components




  • • Usually disseminated disease

    • Anterior compartment most common but can be anywhere in mediastinum

    • Second most common mass in anterior mediastinum




  • • Mediastinal masses account for < 20% of all thoracic tumors

    • Most masses in adults are benign, with recent shift toward more malignant tumors

    • Prevalence: Substernal goiter is most common, then neurogenic tumors (26%), cysts (21%), teratodermoids (16%), thymomas (12%), lymphomas (12%)

    • 25% of masses are malignant


Symptoms and Signs


  • • Symptoms more common in malignant lesions

    • 50% of patients have cough, wheezing, dyspnea, or recurrent pneumonias

    • Hemoptysis, chest pain, weight loss, and dysphagia less common, each occurring in 10% of patients

    • Myasthenia, fever, superior vena cava (SVC) obstruction, each occurring in 5%

    • Cancer suggested if following symptoms are present:

    • -Hoarseness

      -Horner syndrome

      -Severe pain

      -SVC obstruction

      -Chylothorax (lymphoma)

    • Fever in Hodgkin disease

    Thymoma: Myasthenia (15-20%), hypogammaglobulinemia, Whipple disease, red blood cell aplasia, Cushing disease

    Hypoglycemia: Rarely in mesothelioma, teratoma, fibroma

    • Hypertension and diarrhea in pheochromocytoma and ganglioneuroma

    • Neurologic deficits from neurogenic tumors


Laboratory Findings


  • • > 90% of germ cell tumors produce βhCG, alpha-fetoprotein (AFP), lactic dehydrogenase (LDH)


Imaging Findings


  • Chest film: Demonstrates mass

    Chest CT: Diagnostic test of choice


    • -Useful to assess vascular or spinal cord extension

      -In neurogenic tumors, determines intraspinal extension


Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.


About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessSurgery Full Site: One-Year Subscription

Connect to the full suite of AccessSurgery content and resources including more than 160 instructional videos, 16,000+ high-quality images, interactive board review, 20+ textbooks, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessSurgery

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.