Bone metastases in patients with relapsed/refractory germ cell tumors (GCT) undergoing first salvage chemotherapy: A retrospective analysis of a large international database.

• DOI: 10.1200/jco.2012.30.15_suppl.4597
• Publication Date: 2020-03-11T19:16:00Z
• Authors: Karin Oechsle; Christoph Oing; Friedemann Honecker; Lars Arne Berger; Carsten Bokemeyer; Joerg Beyer; Anja Lorch
• Keywords: 03 medical and health sciences; 0302 clinical medicine; 3. Good health

4597 Background: Bone metastases (mets) are rare events in GCT patients (pts) and data on characteristics, risk factors, treatment and outcome in these pts are largely missing. Methods: A subgroup of 104 ptswith bone metsfrom the IPFSG database was analyzed. All patients experienced unequivocal relapse/progression after > 3 cycles of cisplatin-based chemotherapy and received conventional-dose (CDCT) or high-dose salvage chemotherapy (HDCT). Results: 104 / 1594 pts presented with bone mets (6,5%) at first relapse. Histology was pure seminoma in 26%, and non-seminoma in 74%. At initial diagnosis, 54% of pts had presented with "poor risk" according to IGCCCG. Overall response rate (ORR; CR+PR) to 1st-line chemotherapy was 89%. Median PFS after primary treatment was 3 months (range 0 - 140). Bone mets at first relapse were accompanied by abdominal, lung, mediastinal, liver and brain mets in 54%, 48%, 28%, 36%, and 14%, respectively. Tumor marker profiles were heterogeneous (elevation of AFP / ß-HCG: 51% / 37%). Salvage treatment was CDCT in 34%, and HDCT in 66% of pts. ORR to salvage chemotherapy was 68% for the total cohort, and 43% vs. 81% for CDCT vs. HDCT (p<.01). For the total cohort, 2y-PFS and 5y-OS were 24% and 16%, respectively. 2y-PFS and 5y-OS were significantly higher in pts after HDCT compared to CDCT (2y-PFS 29% vs. 14%, p=.01; 5y-OS 19% vs. 9%, p=.04). Conclusions: Pts relapsing with bone mets after platinum-based CTX were characterized by "poor risk" disease at initial diagnosis, but characteristics at first relapse were heterogeneous. Treatment response and outcome was improved in pts with HDCT compared to CDCT. Further prospective evaluation of characteristics and treatment approaches in GCT pts with bone mets is warranted.