PURPOSE To test the equivalence of three versus four cycles of bleomycin, etoposide, and cisplatin (BEP) and of the 5-day schedule versus 3 days per cycle in good-prognosis germ cell cancer. PATIENTS AND METHODS The study was designed as a 2 x 2 factorial trial. The aim was to rule out a 5% decrease in the 2-year progression-free survival (PFS) rate. The study included the assessment of patient quality of life. A cycle of BEP consisted of etoposide 500 mg/m(2), administered at either 100 mg/m(2) days 1 through 5 or 165 mg/m(2) days 1 through 3, cisplatin 100 mg/m(2), administered at either 20 mg/m(2) days 1 through 5 or 50 mg/m(2) days 1 and 2. Bleomycin 30 mg was administered on days 1, 8, and 15 during cycles 1 through 3. The randomization procedure allowed some investigators to participate only in the comparison of three versus four cycles. RESULTS From March 1995 until April 1998, 812 patients were randomly assigned to receive three or four cycles: of these, 681 were also randomly assigned to the 5-day or the 3-day schedule. Histology, marker values, and disease extent are well balanced in the treatment arms of the two comparisons. The projected 2-year PFS is 90.4% on three cycles and 89.4% on four cycles. The difference in PFS between three and four cycles is -1.0% (80% confidence limit [CL], -3.8%, +1.8%). Equivalence for three versus four cycles is claimed because both the upper and lower bounds of the 80% CL are less than 5%. In the 5- versus 3-day comparison, the projected 2-year PFS is 88.8% and 89.7%, respectively (difference, -0.9%, (80% CL, -4.1%, +2.2%). Hence, equivalence is claimed in this comparison also. Frequencies of hematologic and nonhematologic toxicities were essentially similar. Quality of life was maintained better in patients receiving three cycles; no differences were detected between 3 and 5 days of treatment. CONCLUSION We conclude that three cycles of BEP, with etoposide at 500 mg/m(2), is sufficient therapy in good-prognosis germ cell cancer and that the administration of the chemotherapy in 3 days has no detrimental effect on the effectiveness of the BEP regimen.