Metastatic Pure Seminomas With Early Relapse: Prognostic Roles of High Dose Chemotherapy and Surgery of Residual Disease

Abstract

Introduction

Metastatic seminomatous germ cell tumors (mSGCT) are a rare form of cancer. Few studies focused on early relapse (<12 months) after first-line chemotherapy (ChT). We aimed to retrospectively evaluate the impact of salvage retroperitoneal lymph node dissection (RPLND) and high-dose ChT with hematopoietic stem cell transplantation (HDCT-HSCT) in mSGCT patients in a situation of early relapse.

Methods

Ninety-one mSGCT patients treated between 2005 and 2023 in 7 French expert centers for an early recurrence after an initial favorable response to first-line ChT were retrospectively included. Patient clinical characteristics, progression-free survival after first relapse (PFS) and overall survival (OS) were evaluated. We also assessed the role of HDCT-HSCT as first salvage treatment, and the impact of complementary RPLND after salvage ChT.

Results

After a median follow-up of 56 months, 3-year PFS and OS rates were 77.6% (95% CI, 68.3-88.1) and 88.4% (95% CI, 81.0-96.4), respectively. HDCT-HSCT was not associated with longer PFS or OS compared to standard-dose second-line ChT. In contrast, patients who underwent RPLND after salvage ChT demonstrated significantly longer PFS (at 3-years: 97.1% vs. 63%; HR 0.15; 95% CI, 0.03-0.65; P = .012) and a notable trend towards improved OS (at 3-years: 97.0% vs. 81.8%; HR 0.15; 95% CI, 0.02-1.23; P = .078).

Conclusion

RPLND after salvage treatment could be associated with improved PFS and OS in mSGCT patients with first-year relapse. However, the retrospective nature of the study limits causal inference, and prognostic factors influencing treatment selection should be further explored. Identifying subpopulations that might benefit from HDCT-HSCT is warranted.