Appropriate radiation volume for stage IIA/B testicular seminoma.

PURPOSE: Prophylactic left supraclavicular fossa irradiation has been suggested to reduce relapse rates in patients treated for Stage IIA/B testicular seminoma. To address this issue, we reviewed patterns of failure and treatment outcome in patients treated with radiation therapy at our institution.

METHODS AND MATERIALS: Between 1981 and 1999, 79 men with Stage II seminoma (IIA, 49; IIB, 30) were treated with radiation therapy (RT) to the para-aortic and ipsilateral (+/- contralateral) pelvic lymph nodes (dose: 25-35 Gy).

RESULTS: With a median follow-up of 8.5 years, the 5-year relapse-free rate was 91% (standard error: 3%), and 2 patients have died of seminoma, giving a 5-year cause-specific survival of 97%. A total of 7 patients have relapsed with 2 isolated to the left supraclavicular fossa. Five of 7 patients have been successfully salvaged.

CONCLUSIONS: Prophylactic left supraclavicular fossa irradiation might have prevented relapse in 2 of 79 patients in Stage IIA/B seminoma. However, 97% of patients would have received unnecessary left neck RT, so we continue to recommend, as standard treatment, infradiaphragmatic RT only.