Concurrent chemoradiotherapy for unresectable thymic carcinoma

Thymic carcinoma is a rare anterior mediastinal neoplasm. It is more invasive and has a poorer prognosis than ordinary thymoma. Complete curative resection is frequently impossible to achieve because of extensive invasion or metastasis at diagnosis. The role of systemic chemotherapy and the optimal regimen in thymic carcinoma remain uncertain. We report our experience with 16 patients with unresectable thymic carcinoma who underwent concurrent chemoradiotherapy.

Between July 1989 and July 2003, 29 patients were diagnosed with unresectable thymic carcinoma at our hospital. Sixteen of the 29 patients were treated with concurrent chemoradiotherapy. There were 10 men and 6 women whose ages ranged from 45 to 66 years old. Chemotherapy regimens consisted of either (A) cisplatin plus 5-fluorouracil or (B) doxorubicin, cisplatin, vincristine and cyclophosphamide every 4 weeks for at least 2 cycles. Radiotherapy was given concurrently and ranged from 34.2 to 70 Gy.

There were 4 (25.0%) patients with complete responses, 4 (25.0%) with partial responses, 6 (37.5%) with stable disease and 2 (12.5%) with progressive disease. The overall response rate was 50%. The median follow-up was 64 months, and the median survival was 82 months. The overall cumulative survival rates at 1, 2, 3, and 5 years were 93.8%, 81.3%, 74.5%, and 67.7%, respectively. The most common side effects were Grade I/II toxicity, including vomiting, fatigue, and esophagitis. All patients experienced radiation pneumonitis. No life-threatening side effects were noted.

Concurrent chemoradiotherapy seems effective for unresectable thymic carcinoma. Our experience, although preliminary, is encouraging and merits conducting a randomized trial to determine the impact of concurrent chemoradiotherapy on unresectable thymic carcinoma.