Postoperative Conformal Radiotherapy for Stage II-III B Type Thymoma

A Multi-institutional, Randomized Controlled Trial of Postoperative Conformal Radiotherapy for Stage II-III B Type Thymoma

The purpose of this study is to determine whether postoperative conformal radiotherapy are effective in the treatment of Masaoka stage II-III B type thymoma.

The role of postoperative radiotherapy in thymoma is controversial. Some retrospective studies were for the radiotherapy, but others were against. However, more inherent biases existed in these trials. Resection, Masaoka stage and pathology were widely accepted as the prognostic factors for thymoma. Furthermore, the frequency of local failure after radical resection was still high in Masaoka stage II-III B type thymoma. With the conformal technique appearing, conformal radiotherapy can escalate the dose without increasing the risk of normal tissue toxicities.

local control: tumor recurrence in the tumor bed 3 year local control rate: number of patients with tumor recurrence in the tumor bed at 3 years

failure-free survivail: the interval from the surgery and the recurrence within or out the tumor bed overall survival: the interval from the surgery and the death or lost of follow-up

toxicity: including the acute radition-induced lung toxicity and the late lung toxicity at 1, 3, 6, 9, 12, 18, 24, 30 and 36 month after radiation or observation

quality of life: FACT-Lung and EORTC QOL C30 before and after radiation, and at 1, 3, 6, 9, 12, 18, 24, 30, 36 months after radiation or observation

Inclusion Criteria: Age 18-75, Zubrod-ECOG-WHO 0-2, the interval of surgery to radiotherapy < 2months, Masaoka stage II-III and WHO B type thymoma Exclusion Criteria: No second primary tumor, no serious comorbidity, no neoadjuvant anticancer treatment, no adjuvant chemotherapy.