Fourteen patients with testicular nonseminomatous germ cell tumor, clinical stage I were entered into a surveillance study. Median age was 31 (range 18-58). Three patients had pure tumor, and 11, mixed tumor. In 2 patients, vascular invasion was noted, and in 1, involvement of the spermatic cord. Serum alpha fetoprotein and beta subunit choriogonadotropin were high in 9 and in 3 patients, respectively. In median follow-up of 21 months (range 2-63), 3 patients relapsed: 1 had inguinal lymphadenopathy and 2 had lung metastases at 12, 4, and 16 months, respectively. Salvage chemotherapy PEB and PVB achieved complete response in the latter 2 patients for 6 and 49 months. Except for 1 patient lost to follow-up, all are alive.