Seminoma of the testis: long-term beneficial and deleterious results of radiation.

PURPOSE: The followup of 387 patients in a USA national survey of seminoma treated with radiation in 1973 and 1974 has been extended beyond 15 years to assess the long-term benefits and problems resulting from treatment.
RESULTS: Survival at 15 years is 83% for Stage I, 68% for Stage II; freedom from recurrence at 15 years is 93% for Stage I, 96% for Stage II; NED survival at 15 years is 80% for Stage I, 68% for Stage II; cause specific freedom from cancer death is 98% for Stage I and 97% for Stage II at 15 years. Second malignancy rates were 8% at 15 years, and observed in 14 patients versus 4.2 expected (p < .001). Deaths due to these second cancers were also increased with seven observed versus two expected (p < .01). Non-cancer intercurrent disease death occurred in 23 patients versus 7.5 expected (p < .01). The most frequent cause was cardiac death which appeared in 10 patients versus 4.4 expected (p < .05) and 8 of the 10 patients received mediastinal radiation. Two additional patients died of pulmonary fibrosis after mediastinal radiation. Mediastinal radiation correlated with all intercurrent disease and cardio-pulmonary deaths (p < .05), but not with second malignancies. With the exception of one, all patients experiencing cardiac death after mediastinal irradiation were 40 years or older at the time of treatment, with a range of 32-58 years and a mean interval to death of 9.8 years.
CONCLUSIONS: Recommendations for the future management of seminoma include: reducing the irradiated volume in the treatment of Stage I patients, completely eliminating mediastinal radiation in the treatment of patients with Stage IIA seminoma and treating patients with Stage IIB seminoma with chemotherapy. Radiation dose should not exceed 30 Gy for Stage I or 35 Gy for Stage IIA.