Risk Factors for Relapse in Nonseminomatous Testicular Cancer After Postchemotherapy Retroperitoneal Lymph Node Dissection With Viable Residual Cancer.

Purpose: No consensus exists on the management of men with nonseminoma and viable nonteratomatous germ cell tumor in the postchemotherapy retroperitoneal lymph node dissection (pcRPLND) specimen after first-line chemotherapy. We analyzed surveillance versus different adjuvant chemotherapy regimens and the influence of time to pcRPLND on oncologic outcomes.
Methods: Data on 117 men treated with cisplatin-based first-line chemotherapy between 1990 and 2018 were collected from 13 institutions. All patients had viable nonteratomatous germ cell tumor in the pcRPLND specimen. Surgery was performed after a median of 57 days, followed by either surveillance (n = 64) or adjuvant chemotherapy (n = 53). Primary end points were progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS).
Results: After controlling for International Germ Cell Cancer Cooperative Group risk group and percent of viable malignant cells found at RPLND, no difference was observed between men managed with surveillance or adjuvant chemotherapy regarding PFS (hazard ratio [HR], 0.72 [95% CI, 0.32 to 1.6]; P = .4), CSS (HR, 0.69; 95% CI, 0.20 to 2.39; P = .6), and OS (HR, 0.78 [95% CI, 0.25 to 2.44]; P = .7). No statistically significant differences for PFS, CSS, or OS were observed on the basis of chemotherapy regimen or in men treated with pcRPLND ≤57 versus >57 days after first-line chemotherapy. Residual disease with <10% versus ≥10% viable cancer cells were associated with a longer PFS (HR, 3.22 [95% CI, 1.29 to 8]; P = .012). Relapse in the retroperitoneum was observed in 34 (29%) men.
Conclusion: Men with a complete resection at pcRPLND and <10% viable cells have favorable outcomes without further treatment. Complete retroperitoneal resection seems more important than early pcRPLND.