High-Dose Chemotherapy and Autologous Stem Cell Transplantation for Salvage Therapy of Relapsed/Refractory Germ Cell Tumors: A Single-Center Experience.

Introduction: The optimal management of relapsed/refractory germ cell tumors remains unsettled. In this study, we aimed to evaluate the efficacy of high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT) as salvage therapy in patients who progressed after at least one line of cisplatin-based chemotherapy.

Methods: We retrospectively reported the results of 133 patients who underwent HDCT and ASCT as salvage therapy from 2016 to 2021. Patients received 3 cycles of paclitaxel, ifosfomide and cisplatin (TIP) regimen as induction and 1 cycle of carboplatin 700 mg/m2 on days 1-3 plus etoposide 750 mg/m2 on days 1-3, followed by ASCT. Demographic and clinicopathological features of patients, the International Germ Cell Cancer Collaborative Group (IGCCCG) risk group at diagnosis, serum alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (HCG) levels before HDCT, treatment-related complications and survival outcomes were recorded.

Results: The median age of the patients was 31 (range 18-62). The median follow-up was 31.1 months (95% CI, 28.9-33.3 months). During the median follow-up period, 74 of the 133 patients were still alive, and 63 of these were in complete remission. The median progression-free survival (PFS) was 25.8 months (95% CI, 8.1-43.4 months). The 2-year PFS rate was 50.3% and the 2-year overall survival (OS) rate was 60.8%. Variables that remained statistically significant in multivariable analysis and were associated with poor prognosis were mediastinal primary tumor location, presence of brain metastases, and higher AFP and HCG levels at baseline.

Conclusion: One course of HDCT and ASCT after induction with TIP is an effective and feasible treatment option for salvage treatment of relapsed/refractory germ cell tumors, with cure rates of up to 60%.