High-dose versus conventional-dose chemotherapy as first-salvage treatment in patients with non-seminomatous germ-cell tumors: a matched-pair analysis

Background: The purpose of this study was to compare high-dose chemotherapy (HDCT) with conventional-dose chemotherapy (CDCT) as first-salvage treatment in patients with relapsed or refractory non-seminomatous germ-cell tumors (NSGCT). Patients and methods: One hundred and ninety-three patients with relapsed or refractory NSGCT. between 1981 and 1995, were identified from two large databases. In 74 of these, intensification of first-salvage treatment by HDCT was planned. Patients were matched based on primary tumor location, response to first-line treatment, duration of this response and serum levels of the tumor markets, human chorionic gonadotrophin (HCG) and alpha-fetoprotein (AFP). Multivariate analyses were performed using event-free survival and overall survival as primary endpoints. Results: Full matches on all five factors were found for 38 pairs of patients; for a further 17 pairs, matches on at least four factors could be identified. Hazard ratios in favor of HDCT were obtained between 0.72 and 0.84 [confidence interval (CI) 0.59-1.01] for event-free survival and between 0.77 and 0.83 (CI 0.60-0.99) for overall survival, depending on the type of analysis. Conclusions: The current analysis suggests a benefit from HDCT. with an estimated absolute improvement in event-free survival of between 6 and 12% and in overall survival of between 9 and 11% at 2 years. This benefit is lower than expected from previous phase I/II studies.