Risk-Stratified Initial Salvage Therapy for Relapsed or Refractory Metastatic Germ Cell Tumors

Abstract

Background: Salvage treatment with either conventional-dose chemotherapy (CDCT) or high-dose chemotherapy with autologous stem cell transplantation (HDCT) offers curative potential for patients with relapsed or refractory germ cell tumor (GCT). However, the optimal initial salvage strategy remains controversial, and the criteria for appropriate patient selection are not clear.

Methods: This was a retrospective analysis of the clinical outcomes for GCT patients receiving initial salvage therapy using a risk-stratified treatment approach. In general, patients with favorable-risk disease received CDCT with 4 cycles of paclitaxel, ifosfamide, and cisplatin, while patients with unfavorable-risk disease received HDCT per institutional protocol. The prognostic validity of the International Germ Cell Cancer Collaborative Group (IGCCCG) and the International Prognostic Factors Study Group (IPFSG) risk groups were evaluated in this context.

Results: Thirty-seven patients received initial salvage therapy. Twenty-four patients (65%) achieved a favorable response (including complete response to chemotherapy alone, complete response after post-chemotherapy surgical resection, or partial response with negative tumor markers). The favorable response rates for the CDCT and HDCT treatment groups were 69% and 62%, respectively. After a median follow-up of 31 months, the median survival for CDCT-treated patients has not been reached, and the median survival for the HDCT-treated group was 24 months. Both the International Germ Cell Cancer Collaborative Group and the International Prognostic Factors Study Group risk groups were significantly associated with progression-free survival (log-rank P = .009 and P = .039, respectively).

Conclusions: Patients with favorable prognostic features may achieve durable remissions without requiring high-dose salvage chemotherapy. However, the criteria for optimal patient selection remain unclear, and these findings further support the need for a definitive randomized trial.

Keywords: Autologous stem cell transplant; High-dose chemotherapy; Progression-free survival; Risk classification; Testicular cancer.