Schwannoma (Mediastinal Mass)


Published on

  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Schwannoma (Mediastinal Mass)

  1. 5. Evaluation of Mediastinal Mass Leslie Proctor, M.D. November 21, 2008
  2. 6. Mediastinal Anatomy <ul><li>Includes structures bound by: </li></ul><ul><ul><li>the thoracic inlet </li></ul></ul><ul><ul><li>diaphragm </li></ul></ul><ul><ul><li>sternum </li></ul></ul><ul><ul><li>vertebral bodies </li></ul></ul><ul><ul><li>and pleura </li></ul></ul><ul><li>Has 3 compartments </li></ul><ul><ul><li>Anterior </li></ul></ul><ul><ul><li>Middle </li></ul></ul><ul><ul><li>Posterior </li></ul></ul>
  3. 7. The differential diagnosis of a mediastinal mass depends upon the anatomic compartment in which it arises. Redrawn from Baue, AE, et al. Glenn's Thoracic and Cardiovascular Surgery. 5th ed. Appleton & Lange, Norwalk, CT, 1991.
  4. 8. Mediastinal Anatomy <ul><li>Anterior Compartment includes: </li></ul><ul><li>Thymus </li></ul><ul><li>Extrapericardial aorta and its branches </li></ul><ul><li>The great veins </li></ul><ul><li>Lymphatic tissue. </li></ul><ul><li>Middle Compartment is bounded by: </li></ul><ul><li>The pericardium anteriorly </li></ul><ul><li>The posterior pericardial reflection </li></ul><ul><li>The diaphragm </li></ul><ul><li>The thoracic inlet. </li></ul><ul><li>This compartment includes the heart, intrapericardial great vessels, pericardium, and trachea. </li></ul><ul><ul><li>Extends from the posterior pericardial reflection to the posterior border of the vertebral bodies and from the first rib to the diaphragm. </li></ul></ul><ul><ul><li>It includes the esophagus, vagus nerves, thoracic duct, sympathetic chain, and azygous venous system </li></ul></ul>Posterior Compartment:
  5. 9. Anatomic Distribution of Masses <ul><li>Anterior Mediastinum </li></ul><ul><li>Thymic tumors and cysts </li></ul><ul><li>Germ cell tumors </li></ul><ul><li>Lymphomas </li></ul><ul><li>Intrathoracic goiter and thyroid tumors </li></ul><ul><li>Parathyroid adenomas </li></ul><ul><li>Connective tissue tumors </li></ul><ul><ul><li>lipomas and liposarcomas </li></ul></ul><ul><ul><li>lymphangiomas </li></ul></ul><ul><ul><li>hemangiomas </li></ul></ul><ul><li>Thymoma </li></ul>
  6. 10. Anatomic Distribution of Masses <ul><li>Middle Mediastinum </li></ul><ul><li>Thyroid tumor or goiter </li></ul><ul><li>Tracheal tumors </li></ul><ul><li>Aortopulmonary paraganglioma </li></ul><ul><ul><li>paracardial cysts </li></ul></ul><ul><ul><li>bronchogenic cysts </li></ul></ul><ul><ul><li>lymphoma </li></ul></ul><ul><li>Lymphadenopathy </li></ul><ul><li>Retrosternal Goiter </li></ul>
  7. 11. Anatomic Distribution of Masses <ul><li>Posterior Mediastinum </li></ul><ul><li>Neurogenic tumors </li></ul><ul><ul><li>including Schwannomas </li></ul></ul><ul><li>Esophageal tumors </li></ul><ul><li>Hiatal Hernias </li></ul><ul><li>Neurenteric Cysts </li></ul><ul><li>And rarely </li></ul><ul><ul><li>extramedullary hematopoiesis </li></ul></ul><ul><ul><li>pancreatic pseudocyst </li></ul></ul><ul><ul><li>achalasia </li></ul></ul><ul><li>Paraspinal Ganglioneuroma </li></ul>
  8. 12. About Neurogenic tumors… <ul><li>9 to 39 percent of all mediastinal tumors </li></ul><ul><li>develop from mediastinal peripheral nerves, sympathetic and parasympathetic ganglia, and embryonic remnants of the neural tube. </li></ul><ul><li>most frequent in the posterior compartment of the mediastinum </li></ul><ul><li>Can cause neurologic symptoms by compression. </li></ul><ul><li>Benign Schwannoma is most common </li></ul><ul><ul><li>often asymptomatic, but can be associated with Horner’s or Pancoast’s syndrome </li></ul></ul><ul><ul><li>Focal calcifications and cystic changes </li></ul></ul><ul><ul><li>can extend through an intervertebral foramen, resulting in dumbbell-shaped tumors, and neurologic symptoms of spinal cord compression </li></ul></ul><ul><ul><li>Gross Histology </li></ul></ul><ul><ul><ul><li>encapsulated, solid, soft, yellow-pink nodule, with the capsule attached to the epineurium of the nerve that gives rise to the neoplasm </li></ul></ul></ul><ul><ul><li>Microscopic histology </li></ul></ul><ul><ul><ul><li>composed of spindle cells with elongated nuclei, forming interlacing bundles with focal nuclear palisading </li></ul></ul></ul><ul><ul><ul><li>nuclear atypia, and stromal sclerosis in older lesions </li></ul></ul></ul><ul><ul><ul><li>Mitotic figures are rare. </li></ul></ul></ul><ul><ul><ul><li>Immunohistochemical studies reveal a strongly positive reaction with S-100 protein. </li></ul></ul></ul>
  9. 13. Mediastinal Benign Schwannoma
  10. 14. Anatomic Distribution of Masses <ul><li>A mass may extend beyond these boundaries as it grows in size </li></ul><ul><li>In adults, anterior compartment masses are more likely to be malignant </li></ul>
  11. 15. Age Distribution <ul><li>Age can help predict etiology of the mass </li></ul><ul><ul><li>infants and children, neurogenic tumors and enterogenous cysts are the most common mediastinal masses </li></ul></ul><ul><ul><li>In adults, neurogenic tumors, thymomas, and thymic cysts are most frequently encountered lesions </li></ul></ul><ul><ul><li>In 20-40 year olds, the likelihood of a mass being malignant is greater secondary to the increased incidence of lymphoma (Hodgkin’s and non-Hodgkin's) and germ cell tumors </li></ul></ul>
  12. 16. Signs and Symptoms <ul><li>Depend on location of mass </li></ul><ul><li>Asymptomatic </li></ul><ul><li>Vague symptoms </li></ul><ul><ul><li>aching pain </li></ul></ul><ul><ul><li>cough </li></ul></ul><ul><li>Children more likely to be symptomatic </li></ul><ul><ul><li>respiratory difficulty </li></ul></ul><ul><ul><li>recurrent pulmonary infections </li></ul></ul>
  13. 17. Signs and Symptoms <ul><li>Airway compression </li></ul><ul><ul><li>recurrent pulmonary infection </li></ul></ul><ul><ul><li>hemoptysis </li></ul></ul><ul><li>Esophageal compression </li></ul><ul><ul><li>dysphagia </li></ul></ul><ul><li>Involvement of the spinal column </li></ul><ul><ul><li>paralysis </li></ul></ul><ul><li>Phrenic nerve damage </li></ul><ul><ul><li>elevated hemidiaphragm </li></ul></ul>
  14. 18. Signs and Symptoms <ul><li>Recurrent laryngeal nerve involvement </li></ul><ul><ul><li>Hoarseness </li></ul></ul><ul><li>Sympathetic ganglion involvement </li></ul><ul><ul><li>Horner’s Syndrome </li></ul></ul><ul><ul><ul><li>Ptosis, miosis, anhidrosis </li></ul></ul></ul><ul><li>superior vena cava involvement </li></ul><ul><ul><li>Superior vena cava syndrome </li></ul></ul><ul><ul><ul><li>facial neck, and UE swelling, dyspnea, chest and UE pain, mental status changes </li></ul></ul></ul>Horner’s Syndrome
  15. 19. Signs and Symptoms <ul><li>Can also be associated with systemic diseases </li></ul><ul><ul><li>Thymoma: myasthenia gravis, immune deficiency, red cell aplastic anemia </li></ul></ul><ul><ul><li>Goiter: thyroxicosis </li></ul></ul><ul><ul><li>Thymic carcinoid: Cushing’s syndrome </li></ul></ul><ul><ul><li>Parathyroid: hyperparathyroidism </li></ul></ul>
  16. 20. Evaluation: Imaging <ul><li>2 view PA/Lat Chest X-ray </li></ul><ul><ul><li>comparisons with old x-rays important </li></ul></ul><ul><li>Chest CT with contrast </li></ul><ul><ul><li>most important method of evaluation </li></ul></ul><ul><ul><li>Can help determine location, morphology, size, and attenutation coefficient </li></ul></ul><ul><ul><li>Important for directing further therapy </li></ul></ul><ul><li>MRI </li></ul><ul><ul><li>when contrast allergy or renal failure present </li></ul></ul><ul><ul><li>when vascular or chest wall involvement is suspected </li></ul></ul><ul><ul><li>neurogenic tumors (especially helpful in detecting intraspinal component </li></ul></ul><ul><li>Ultrasound </li></ul><ul><ul><li>Differentiate cystic from solid masses and relate to surrounding structures </li></ul></ul><ul><ul><li>When mass is close to heart or pericardium </li></ul></ul><ul><ul><li>Transesophageal or transbronchial useful to evaluate lymph nodes, sometimes for biopsy </li></ul></ul><ul><li>Radio nucleotide scanning </li></ul><ul><ul><li>With radioactive iodine when thyroid tumor suspected </li></ul></ul><ul><li>PET scanning </li></ul><ul><ul><li>Can localize specific tumors (pheochromocytoma, paragangliomas, neuroblastomas, neurogangliomas by targeting their metabolic pathways </li></ul></ul>
  17. 21. Evaluation: Laboratory <ul><li>Depends on clinic setting, but may include: </li></ul><ul><ul><li>Thyroid function tests </li></ul></ul><ul><ul><ul><li>If goiter suspected </li></ul></ul></ul><ul><ul><li>Chemistry panel including calcium and phosphate and PTH </li></ul></ul><ul><ul><ul><li>If parathyroid adenoma suspected </li></ul></ul></ul><ul><ul><li>Fractionated 24-hour urinary metanephrines and catecholamines </li></ul></ul><ul><ul><ul><li>If paraganglionic tumor suspected </li></ul></ul></ul><ul><ul><li>AFP/beta HCG </li></ul></ul><ul><ul><ul><li>In all males with anterior mediastinal tumor because of concern for non-seminomatous germ cell tumor </li></ul></ul></ul>
  18. 22. Management <ul><li>Tailored to specific or likely diagnosis </li></ul><ul><li>Must decide whether to excise, biopsy, or aspirate lesion </li></ul><ul><ul><li>Excision should be done with teratomas, thymomas, and isolated masses likely to be benign (VATS, median sternotomy, thoracotomy) </li></ul></ul><ul><ul><li>Needle aspiration of cystic lesions </li></ul></ul><ul><ul><li>Diagnostic biopsy is procedure of choice when suspect lymphoma, germ cell tumor, or unresectable invasive malignancy </li></ul></ul>
  19. 24. References <ul><li>Kallab, Andre MD. Superior Vena Cava Syndrome . Emedicine. August 10 2005. </li></ul><ul><li>Gangadharan, Sidhu MD. Evaluation of Mediastinal Masses. UptoDate. October 7, 2008. </li></ul><ul><li>Parmar, Malvinder S, MB, MS. Horner’s Syndrome. Emedicine. June 5, 2008. </li></ul><ul><li>Strolls, DC, Rosado-de-Christenson, ML, Jett, JR. Primary mediastinal tumors. Part I: Tumors of the anterior mediastinum . Chest 1997; 112:511. </li></ul><ul><li>Strollo, DC, Rosado-de-Christenson, ML, Jett, JR. Primary mediastinal tumors: Part II. Tumors of the middle and posterior mediastinum . Chest 1997; 112:1344. </li></ul><ul><li> (multiple images) </li></ul><ul><li>Devouassoux-Shisheboran, Mojgan MD and Travis, William D MD. Pathology of Mediastnal Tumors. Uptodate. September 9 th , 2008. </li></ul>