Thymic Carcinomas

• • Rare variant of thymic lesions (< 15%)

  • Biologically different from malignant thymoma

  • Tend to be very invasive and aggressive

Epidemiology

• • Young men (< 50-years-old, typically)

Symptoms and Signs

• • 50% of asymptomatic cases identified on chest film

  • Chest pain dysphagia, dyspnea, or superior vena cava syndrome most common if symptomatic

Imaging Findings

• • Chest film: Anterior mediastinal mass

  • CT scan: Useful in assessing extent of lesion

  • MRI: Can assess vascular invasion

• • Definitive diagnosis: Histologic tissue analysis

  • Do not biopsy small, well-encapsulated mediastinal masses-

  • Do complete excision, otherwise risk tumor seeding

Rule Out

• • Lymphoma

  • -Can be difficult to differentiate histologically from thymoma

  • Thymoma

  • -Very aggressive variant of thymic lesions

• • Chest CT

  • Biopsy

• • Attempt complete resection

Medications

• • Induction chemotherapy

  • Postoperative chemoradiation

Prognosis

• • High recurrence locally and at distant sites

  • After thymectomy, 75% with myasthenia gravis are improved; 30% complete remission

  • Younger patients (< 40 years) do better after thymectomy

References

Practice Guidelines

• • National Comprehensive Cancer Network

  • http://www.NCCN.org/