Is There A Role For Conventional-Dose Chemotherapy In Relapsed Germ Cell Tumors?

404 Background: Patients with germ cell tumors (GCT) that relapse after first-line platinum-based chemotherapy can still be successfully rescued with second-line regimens. High-dose chemotherapy has shown favorable outcomes, and is a preferred option in most instances. Herein, we argued if conventional-dose chemotherapy (CDCT) could also be an alternative in selected patients. Methods: We performed a retrospective observational study, analyzing medical data of 57 GCT male patients treated with salvage chemotherapy after relapse to first-line platinum-based treatment from 2000 to 2015 at the Brazilian National Cancer Institute. Results: The median age was 28 years (range 15 to 49). 26 patients (46%) were Afro-Brazilian, 45 (79%) were non-seminoma, and 53 (93%) had primary testis tumors. 14 patients (25%) had bone, liver or brain metastasis at relapse, and in 35 (61%) the progression-free interval (PFI) after first-line was < 3months. The International Prognostic Factors Study Group (IPFSG) risk classification at relapse for very-low/low, intermediate and high/very-high risk were 8 (14%), 25 (44%), 24 (42%), respectively. After a median follow-up of 8 years, the 2-year PFS was 30% (95% IC, 20 % to 45 %) and the 2-year overall survival (OS) was 34% (95% IC, 23% to 49%). PFI < 3m after first-line (HR 2,38; p<0,005) and AFP > 1000 at relapse (HR 2,38, p<0,023) were negative prognostic factors for PFS and OS. The 2-year PFS and OS for IPFSG risk classification very-low/low, intermediate and high/very-high risk were 75% and 73%, 28% and 32%, 18% and 24%, respectively. Conclusions: In patients with relapsed GCT and very-low/low risk disease by the IPFSG classification, CDCT may be a reasonable option, achieving long-term survival rates. However, CDCT was associated with poor outcome in intermediate and high/very-high risk groups. Further studies should be conducted to assess the best treatment in this subset, since even in second-line, many of patients are still potentially curable.