A total of 145 consecutive primary testicular tumors were treated with radiation therapy at the University of Michigan Hospital from 1955 through 1974. In patients with seminoma, the 5-year survival rate was 98% for Stage I and 88% for Stage II regardless of whether retroperitoneal lymph node dissection was done. The 5-year survival rate for embryonal carcinoma was 63% for Stage I and 66% for Stage II. For teratocarcinoma it was 100% for Stage I and 54% for Stage II. Adjuvant chemotherapy appeared to be beneficial for patients with Stage II teratocarcinoma but made no difference in patients with embryonal carcinoma.