Clinical Trials of Chemotherapy for Disseminated Testis and Extragonadal Germ Cell Tumors

Four cycles of bleomycin, etoposide, and cisplatin (BEP) chemotherapy as a standard-of-care treatment option for patients with metastatic testicular germ cell tumors was established by a randomized trial showing that it produced similar outcomes with fewer toxic effects in comparison with cisplatin, vinblastine, and bleomycin (PVB).[3] Two randomized trials comparing four courses of BEP with four courses of etoposide plus ifosfamide plus cisplatin (VIP) showed similar OS and time-to-treatment failure for the two regimens in patients with intermediate- and poor-risk advanced disseminated germ cell tumors who had not received prior chemotherapy.[4-6][Level of evidence A1] Hematologic toxic effects were substantially worse with the VIP regimen. For good-risk patients, two randomized trials compared three versus four cycles of BEP and reported no significant benefit from longer treatment in that population.[7-9]

Numerous attempts have been made to develop a regimen superior to BEP for men with poor-prognosis germ cell tumors but none have been successful. Most recently, four cycles of BEP was compared with two cycles of BEP followed by two cycles of high-dose cyclophosphamide, etoposide, and carboplatin, but there was no difference in survival between the two arms.[10] Earlier trials of higher dose cisplatin or long-term maintenance chemotherapy were similarly disappointing.

For patients with good-risk disease, the goal of clinical trials has been to minimize the toxic effects of treatment without sacrificing the therapeutic effectiveness. As noted above, no difference in outcome was seen when comparing three versus four cycles of BEP chemotherapy. However, attempts to eliminate bleomycin produced more ambiguous and usually disappointing results. A randomized controlled trial comparing three cycles of BEP with three cycles of etoposide and cisplatin (EP) reported lower OS rates (95% vs. 86%, P = .01) in the EP arm.[11] Similarly, when three cycles of BEP was compared with four cycles of EP in a randomized trial in more than 260 patients, there were 6 relapses and 5 deaths in the bleomycin arm compared with 14 relapses and 12 deaths in the EP arm, but these differences were not statistically significant.[12] Several other studies have compared bleomycin-containing regimens to etoposide and cisplatin and in every trial, the trend in survival has favored the bleomycin arm, but the differences have not usually been statistically significant.[13-15] These results have led to some controversy as to whether three cycles of BEP is superior to four cycles of EP.