Doxorubicin, Paclitaxel, and Cisplatin (ATP) for Relapsed/Refractory Germ Cell Tumors

Abstract

Patients with relapsed/refractory germ cell tumors (GCT) have limited treatment options and poor survival outcomes. We describe our institutional experience with doxorubicin, paclitaxel, and cisplatin (ATP) as an outpatient regimen for 35 patients with relapsed/refractory GCT between 2017 and 2022. Twenty-four patients received nonpalliative intent ATP, with a median of 2 lines of prior therapy, 23 (96%) having received at least 1 cisplatin-based regimen and 1 (4%) with a prior stem cell transplant. The objective response rate for the nonpalliative intent cohort was 37.5% (1 complete response and 8 partial responses). Post-ATP, 12 patients underwent stem cell transplant, 7 patients had surgical resections, and 4 patients received radiation. The median PFS was 4.3 months (95% CI: 3.8, 32.7) and median OS of 13.1 months (95% CI: 10.7, NA) for the nonpalliative intent cohort. Eleven patients received palliative intent ATP, with a median of 4 lines of prior therapy, all having received at least 1 cisplatin-based regimen, and 7 (64%) having received prior stem cell transplants. Within the palliative intent cohort, the objective response rate was 9% (1 partial response). Patients who received palliative intent ATP had a median PFS of 0.92 months (95% CI 0.46, NA) and median OS of 5.2 months (95% CI 3.3, NA). Treatment toxicities occurred in 5 (14%) patients who required dose reductions and 5 (14%) patients who were admitted for treatment related toxicities, most commonly for myelosuppression. Our results support the use of ATP in a primarily anthracycline naïve patient population and show the safety of continued cisplatin use in patients who have previously received cisplatin-based regimens. Therefore, ATP is a feasible and well tolerated chemotherapy regimen in the salvage setting and can serve as a bridge to other treatments for patients with relapsed/refractory GCT.

Keywords: anthracycline naive patient population; nonpallaitive intent cohort; palliative intent cohort; treatment toxiciites.