Primary retroperitoneal lymph node dissection for clinical stage II seminoma: Comparative analysis against established paradigms using the National Cancer Data Base

Abstract Objectives This paper aims to perform a comparative, real‐world analysis of outcomes after primary retroperitoneal lymph node dissection (pRPLND) for clinical stage II (CSII) seminoma. Patients and Methods Using the National Cancer Data Base, we identified patients with CSII germ cell tumours (GCT) between 2004 and 2022. Cox regression was used for survival analyses. Primary analysis examined overall survival (OS) for patients with CSII seminoma. A sensitivity analysis after energy‐balancing weighting was performed. Secondary analysis examined salvage‐chemotherapy‐free survival (SFS) after pRPLND for CSII seminoma. Results Primary analysis included 4661 patients (median follow‐up 6.8 years, IQR 3.6–10.5 years). OS did not differ by primary treatment (vs. chemotherapy—HR1.34, 95% CI 0.93–1.93, p = 0.12; versus radiation—1.02, 0.65–1.59, p = 0.95). Sensitivity analysis results were similar. Secondary analysis demonstrated estimated 2‐year salvage chemotherapy‐free survival rates of 70%, 45% and 36% for cN1, cN2 and cN3, respectively. Unaccounted bias should be considered given the retrospective nature of the underlying data. Conclusion OS after pRPLND for CSII seminoma appears comparable to alternatives. Risk of receiving salvage chemotherapy increases with clinical disease extent.