• Thoracic meningocele
• Large normal thymus in neonate
• Bronchogenic cyst
• Pericardial cyst
• Aortic aneurysm

• Tuberculosis
• Histoplasmosis
• Aspergillosis
• Coccidioidomycosis
• Blastomycosis

• Foreign body in the trachea or esophagus

• Benign
  • Thymoma
  • Teratoma/dermoid cyst
  • Lymphangioma/cystic hygroma
  • Hemangioma
  • Pheochromocytoma
  • Ganglioneuroma
  • Neurofibroma
• Malignant
  • Hodgkin disease
  • Non-Hodgkin lymphoma
  • Leukemia
  • Neuroblastoma
  • Rhabdomyosarcoma
  • Ganglioneuroblastoma
  • Neurofibrosaroma
  • Ewing sarcoma

• Sarcoid

• Benign or malignant tumors
• Foreign bodies
• Infection
• Cysts

• Superior vena cava (SVC) syndrome—mass compression of the SVC resulting in decreased blood flow to the heart.
• Tracheal compression
• Spinal cord compression
• Pleural and/or pericardial effusion
• Tumor lysis syndrome—metabolic triad of hyperkalemia, hyperuricemia, and hyperphosphatemia

• If mass appears solid, attempt to obtain a tissue diagnosis via biopsy or excision of mass
• If mass appears cystic, a surgical consult may be indicated
• If patient exhibits signs of infection (fever, cough, etc.), obtain appropriate cultures, place PPD and anergy panel and begin broad-spectrum antibiotics

• Be aware that the child may be asymtomatic; the mass may be an incidental finding on chest x-ray.
• A PPD and anergy panel should always be part of the initial evaluation of a mediastinal mass if the etiology is not immediately evident.

• Superior vena cava (SVC) syndrome: mass compression of the SVC resulting in decreased blood flow to the heart; signs and symptoms include edema and cyanosis of the face, neck, and upper extremities, plethora, distended neck veins, cough, dyspnea, orthopnea, headache, anxiety, and confusion. Symptoms are exacerbated when child is recumbent.
• Tracheal compression: mass compression of the trachea resulting in respiratory compromise; signs and symptoms include stridor, cough, dyspnea, orthopnea.
• Spinal cord compression: symptoms vary depending on the level of the lesion.
• Pleural and pericardial effusions: resulting in respiratory distress or cardiac tamponade.
• Infection: may be the primary mass (tuberculosis) or a complication of the mass (infected cyst, infected nodes).
• Horner syndrome: ptosis, miosis, and anhydrosis resulting from compression of the cervical sympathetic nerve trunk.
• Esophageal narrowing or erosion: may result in feeding difficulty or bleeding.

Question: Chest pain
Significance: May indicate rapidly enlarging mass

Question: Respiratory distress: stridor cough, dyspnea, orthopnea, wheezing
Significance: May indicate tracheal compression

Question: Headache, syncope, dyspnea, orthopnea, anxiety, facial swelling, eye edema
Significance: SVC syndrome

Question: Fever
Significance: Associated with infection

Question: Weight loss, night sweats
Significance: Associated with malignancies

Question: Fatigue, malaise
Significance: Associated with malignancies or infection

Finding: Decreased breath sounds, wheezing, stridor
Significance: Mass may be impinging on trachea or bronchi

Finding: Diaphoresis
Significance: Seen in Hodgkin disease

Finding: Edema and cyanosis of face, neck, and upper extremities
Significance: Seen in SVC syndrome

Finding: Venous distention (jugular and superficial chest veins)
Significance: Seen in SVC syndrome

Finding: Conjunctival edema, retinal vessel engorgement
Significance: Seen in SVC syndrome

Finding: Lymphadenopathy and/or hepatosplenomegaly
Significance: Systemic process such as Hodgkin disease

Finding: Generalized bruises, petechiae, mucosal bleeding
Significance: Bone marrow involvement as in leukemia

Finding: Upper extremity and facial petechiae
Significance: Seen in SVC syndrome

• Avoid supine position in suspected SVC syndrome.
• In SVC syndrome, when the right arm is elevated the veins may remain full.

Test: CBC with differential
Significance: Anemia, thrombocytopenia, or leukocytosis frequently noted in leukemia or lymphoma syndromes

Test: LDH, uric acid
Significance: Frequently elevated in leukemia or lymphoma syndromes

Test: Arterial blood gas
Significance: Helpful to assess tissue oxygenation if respiratory distress noted

Test: Chest x-ray (lateral film required)
Significance: Establish size and location of mass

Test: Computed tomography (CT) of the chest (if patient can tolerate recumbency)
Significance: Define size, location, and consistency of mass

Test: Magnetic resonance imaging (MRI) of the chest
Significance: Define size, location, and consistency of mass

Test: Diagnostic: lymph node aspiration/biopsy, bone marrow aspiration/biopsy, PPD skin test for tuberculosis
Significance: Establish diagnosis

Test: Diagnostic and therapeutic: pleurocentesis or pericardiocentesis, biopsy or excision of mass
Significance: Establish tissue diagnosis and relieve symptoms

• Chemotherapy and/or radiation therapy for malignant tumors
• Surgical removal to establish diagnosis (pathology may be benign, malignant, or infectious) and relieve symptoms
• Antibiotics for infectious process

• Radiation therapy
• Steroids (may obscure the diagnosis of leukemia/lymphoma)
• Surgery

• Establish diagnosis and begin treatment promptly when leukemia or lymphoma is suspected because both tumors grow rapidly.
• Monitor for evidence of tumor lysis syndrome (metabolic triad of hyperkalemia, hyperuricemia, and hyperphosphatemia), which may develop early as leukemia or lymphoma is being treated.

• General anesthesia: try to make the diagnosis with local or no anesthesia
• Sedation: may cause irreversible respiratory depression
• Supine position: keep head elevated to increase venous return
• Placing intravenous line in the upper extremities due to poor venous return: try to use lower extremities
• Long delays in establishing diagnosis: leukemia and lymphomas grow quickly and can rapidly impinge on vital structures

Q: What should be done if the child is asymptomatic and mediastinal mass is an incidental finding on CXR?
A:

Q: When should an oncologist be consulted?
A: With any of the following:

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Maity A, Goldweins JW, Lange BW, D’Angio GJ. Mediastinal masses in children with Hodgkins disease. Cancer 1992;69(11):2755–2760.

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