Thymoma and thymic carcinoma: therapeutic approaches

Thymomas and thymic carcinomas, which are rare epithelial tumors arising from the thymus gland, are the most common tumors of the anterior mediastinum. Thymomas are generally encapsulated, slow-growing tumors that have a "bland" histologic appearance. Thymic carcinomas possess more overtly malignant histologic features than thymomas and are more likely to present as invasive or disseminated disease. Surgery is the treatment of choice for localized thymic tumors, with complete resection being the most important prognostic factor. Complete resection also improves survival in locally invasive thymic tumors. Adjuvant postoperative radiation therapy may improve the outcome in patients with invasive disease, although the data are conflicting. Multimodal regimens, including neoadjuvant combination chemotherapy, surgery, and/or postoperative radiation therapy, are recommended for patients with advanced thymomas and thymic carcinomas. Use of octreotide plus prednisone has produced responses in thymomas, but the dosing and schedule have not been clearly defined. Prospective studies have been limited, and, as such, enrollment in clinical trials is encouraged.