High Dose Chemotherapy with Autologous Stem Cell Transplant for Patients with Advanced Germ Cell Tumors: Real-World Evidence from a Tertiary Cancer Center in Brazil

Background High-dose chemotherapy followed by stem cell transplant (HDCT) is potentially curative for patients with refractory germ cell tumors (rGCT). There is scarce real-world data supporting its implementation in low- and middle-income countries. We described the experience of our tertiary cancer center in Sao Paulo, Brazil. Methods We identified male patients ≥18 years-old with rGCT referred to HDCT after board discussion. Clinical data, including delays in HDCT protocol, were extracted from medical records, and survival outcomes were estimated using the Kaplan-Meier method. The log-rank test and Cox proportional hazard were used to determine effects on overall survival (OS). Results From January 2013 to January 2023, 34 patients were referred and considered eligible to receive 2 cycles of HDCT. Most patients had primary testicular tumors (82%), nonseminomatous histology (88%), and poor International Germ Cell Collaborative Group (IGCCCG) (79%). Twenty-three patients received HDCT (1 cycle, n=8; 2 cycles, n=15). Main reasons for not receiving any HDCT were death due to progressive disease (n=1), performance deterioration (n=7), and failure of stem cell mobilization (n=3). OS at 2 years was 36.7% for the eligible population, 56.1% for patients who underwent at least 1 HDCT, and 77.1% for those who had ≥2 cycles. The 2-year OS rate for patients not given HDCT was 0%. All patients had delays in protocol, and poor-risk patients had longer intervals from referral to protocol initiation (0.7 vs. 1.8 month, p <0.01). Conclusion Outcomes of patients who received ≥1 HDCT were encouraging; however, only 15 from 34 eligible patients were able to receive the planned 2 cycles of HDCT. Further strategies to minimize treatment delays in low- and middle-income countries are needed.