Personalized Chemotherapy on the Basis of Tumor Marker Decline in Poor-Prognosis Germ-Cell Tumors: Updated Analysis of the GETUG-13 Phase III Trial

Abstract

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. GETUG-13 established that switching patients with poor-prognosis nonseminomatous germ-cell tumors with an unfavorable marker decline to intensified chemotherapy resulted in improved outcomes. Here, we report the GETUG-13 long-term efficacy and toxicity. Two hundred and sixty-three patients with International Germ Cell Cancer Consensus Group poor prognosis received one cycle of bleomycin, etoposide, and cisplatin (BEP): 51 with a favorable tumor marker decline continued with three cycles of BEP (Fav-BEP) and 203 with an unfavorable decline were randomly treated with three BEP (Unfav-BEP) cycles or a dose-dense regimen (Unfav-dose-dense; two cycles of paclitaxel-BEP-oxaliplatin + two cycles of cisplatin, ifosfamide, and bleomycin). The median follow-up was 7.1 years (range, 0.3-13.3). Five-year progression-free survival (PFS) rates were 58.9% in the Unfav-dose-dense arm and 46.7% in the Unfav-BEP arm (hazard ratio [HR], 0.65 [95% CI, 0.44 to 0.97]; P = .036). Five-year overall survival rates were 70.9% and 61.3% (HR, 0.74 [95% CI, 0.46 to 1.20]; P = .22). Side effects evolved favorably, with only three patients in the Unfav-dose-dense arm reporting grade 3 motor neurotoxicity at 1 year and no reported toxicity over grade 1 after year 2. Salvage high-dose chemotherapy plus a stem-cell transplant was used in 8% in the Unfav-dose-dense arm and 17% in the Unfav-BEP arm ( P = .035). Long-term outcomes suggest a sustained benefit of intensified chemotherapy in terms of PFS and numerically better survival, with a minimal toxicity and reduced use of salvage high-dose chemotherapy plus stem-cell transplant.