1997 Volume 47 Issue 1 Pages 19-23
The prognostic factors and the correlation between local control and total dose were investigated for the patients with invasive thymoma treated by a combination of radiation therapy and surgery or radiation therapy alone. Eighteen patients were retrospectively analyzed. Our treatment strategy was to give the target volume a total dose of at least 50 Gy for patients with microscopic residual and 60 Gy or more for macroscopic residual. The actuarial survival rates were 61 % at 5 years and 54 % at 10 years in all patients. All patients having a complete resection survived disease-free for more than 6 years while the survival rates of patients with macroscopic residual or unresected tumors were 38 % at 5 years and 25 % at 10 years (p<0.005). For macroscopic residual local recurrence rate within a radiation field was 0 % at a dose of 60 Gy or more, 67 % from 50 to 58 Gy and 100 % under 40 Gy, respectively. Invasive thymoma may be preferable to be treated at the dose of 50 Gy or more for microscopic residual and 60 Gy or more for macroscopic residual. Good prognosis may be expected in the patients undergoing complete resection and radiation therapy.
