Excellent long-term disease control with modern radiotherapy techniques for stage I testicular seminoma--the Mayo Clinic experience.

OBJECTIVES: The objectives of this study are to examine the long-term efficacy and adverse effects of adjuvant radiotherapy (RT) for stage I testicular seminoma.

METHODS AND MATERIALS: A retrospective review was conducted in 199 patients with stage I testicular seminoma treated with curative intent orchiectomy and adjuvant megavoltage RT at the institution from January 1, 1972 through December 31, 2009. Computed tomography staging was performed for 90% of the patients. No patient received mediastinal RT or adjuvant chemotherapy. Overall survival (OS), cause-specific survival, relapse rate, major cardiac event (MCE), and second malignancy (SM) were estimated using the Kaplan-Meier method.

RESULTS: The median age of the patients was 36 years (range: 18-80). The nodal regions irradiated were the para-aortic and ipsilateral pelvic nodes in 147 patients (74%), the para-aortic nodes alone in 34 (17%), and the para-aortic and bilateral pelvic nodes in 18 (9%). The median RT dose was 25.5 Gy (interquartile range: 25-30). The median follow-up after RT was 13 years (range: 0.1-37). OS at 10 and 20 years was 92% and 77%, respectively. Cause-specific survival at 10 and 20 years was both 99%. Risk of relapse at 10 and 20 years was 1% and 2%, respectively. Risks of MCE and SM at 20 years were 12% and 19%, respectively.

CONCLUSIONS: This series confirms an excellent outcome in patients with stage I testicular seminoma treated with RT. Relapse after adjuvant RT is very uncommon, but late morbidity associated with RT may occur.