High-dose chemotherapy with autologous stem cell transplantation in relapsed or refractory germ cell tumours: outcomes and prognostic variables in a case series of 17 patients

Abstract

Background: Optimal therapy for men relapsing after initial chemotherapy for germ cell tumours (GCT) is poorly defined. Both conventional dose salvage regimens and high-dose chemotherapy with autologous stem cell transplantation (HDCT-ASCT) have been utilised.

Aims: To examine patients who received HDCT-ASCT for relapsed GCT within a single Australian centre.

Methods: Records between 2000 and 2012 were analysed for baseline characteristics, treatment-related toxicity and survival. Prognosis at the time of HDCT-ASCT was classified according to the International Prognostic Factors Study Group (IPFSG).

Results: Seventeen patients received HDCT-ASCT, median age 34 (21-46), with 41% having primary refractory disease and 53% with high/very high risk disease by IPFSG. The most common regimen utilised was paclitaxel/ifosfamide followed by high-dose carboplatin/etoposide (TI-CE; n = 12). The median duration of grade 4 (G4) neutropenia was 11 days (range 9-17) with febrile neutropenia in 90% resulting in four intensive care unit admissions (8%). Median duration of G4 thrombocytopenia was 10 days (range 8-19) requiring a median of two pooled platelets bags (range 0-33) per episode. Transplant-related mortality occurred in one patient (veno-occlusive disease). Twenty-seven per cent of HDCT-ASCT cycles were associated with grade 3 mucositis (median total parenteral nutrition days = 5 (0-23)). Two-year progression-free survival (PFS) and overall survival (OS) rates were 59% and 71%. Patients who received HDCT-ASCT as second or subsequent relapse fared worse than those treated with HDCT-ASCT at first relapse (hazard ratio 0.23 (95% confidence interval: 0.04, 1.37; P-value 0.09). Three-year OS for those who received TI-CE at first relapse was 90%.

Conclusions: HDCT-ASCT for relapsed GCT is effective with acceptable toxicity. There was encouraging PFS/OS, particularly in a poor-prognosis cohort.

Keywords: autologous transplantation; germ cell tumour; salvage therapy; stem cell transplantation; testicular neoplasm.