Background: Up to 50% of men with poor prognosis, non-seminoma germ cell tumours (GCTs) die with standard BEP (bleomycin, etoposide and cisplatin) chemotherapy. An intensive regimen, CBOP/BEP (carboplatin, bleomycin, vincristine and cisplatin/BEP), met response targets in a randomised, phase II trial (74% complete response or partial response marker negative, 90% confidence interval (CI) 61%-85%).
Aim: To assess long-term outcomes and late toxicity associated with CBOP/BEP.
Methods: Patients with poor prognosis extracranial GCT were randomised to 4xBEP or CBOP/BEP (2xCBOP, 2xBO, 3xBEP with 15,000iu of bleomycin). Low-dose, stabilising chemotherapy before entry was permitted. Response rates (primary outcome) were reported previously. Here, we report secondary outcomes: progression-free survival (PFS), overall survival (OS) and late toxicity. Prognostic factors and the impact of marker decline are assessed in exploratory analysis.
Results: Eighty-nine patients (43 CBOP/BEP) were randomised. After median 63 months follow-up, 3-year PFS is 55.7% (95% CI: 39.7%, 69.0%) for CBOP/BEP and 38.7% (95% CI: 24.7%, 52.4%) for BEP (hazard ratio [HR]: 0.59 (0.33, 1.06), p = 0.079). Three-year OS is 65.0% (48.8%, 77.2%) and 58.5% (43.0%, 71.2%), respectively (HR: 0.79 (0.41, 1.52), p = 0.49). Twelve-month toxicity was affected by subsequent treatments, with no clear differences between arms. Stabilising chemotherapy was associated with poorer PFS (HR: 2.09 (1.14, 3.81), p = 0.017), whereas unfavourable marker decline, in 60 (70%) patients, was not.
Conclusion: Although not powered for PFS, results for CBOP/BEP are promising. Impact on OS was less clear (and will be affected by subsequent therapy). Further study in an international phase III trial is warranted.
Trial registration: ISRCTN 53643604.
Keywords: Bleomycin; Germ cell tumours; Poor prognosis; Randomised trial.
Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.