First salvage treatment of germ cell tumor patients with bone metastases: retrospective analysis of a large international database.

Purpose: To retrospectively analyze clinical characteristics, prognostic factors, and optimal treatment of patients with bone metastases (BM) of germ cell tumors (GCT) at first relapse.

Methods: One hundred and four GCT patients with BM were identified from the IPFSG database containing 1,594 patients at first relapse. Within this database, all patients experienced unequivocal relapse/progression after cisplatin-based chemotherapy and had received either conventional (CD-CTX) or high-dose chemotherapy (HD-CTX) as first salvage treatment.

Results: At relapse, eight patients (8 %) had BM only, concomitant relapse with lung, brain, liver and/or nodal metastases were present in 40 (39 %), 6 (6 %), 27 (26 %), and 69 (66 %) pts, respectively. Patients clustered over all IPFSG subgroups, and the IPFSG score could be confirmed. Salvage treatment was CD-CTX in 35 and HD-CTX in 69 patients. Overall response (CR, PR) rate to salvage chemotherapy was 81 % (HD-CTX) versus 43 % (CD-CTX; p < 0.001). Median follow-up was 14 months (mos; range 1-161). Both, median PFS and OS, were higher after HD-CTX compared to CD-CTX [PFS 9 (95 % CI 6-12) vs. 5 (3-7) mos (p < 0.01); OS 18 (12-24) vs. 13 (8-18) mos (p = 0.078)].

Conclusions: GCT patients relapsing with BM have a dismal outcome. Retrospectively, first salvage HD-CTX seems to improve treatment response and outcome. Further evaluation of characteristics and treatment of GCT patients with BM is warranted.