Histologic and Oncologic Outcomes Following Liver Mass Resection With Retroperitoneal Lymph Node Dissection in Patients With Nonseminomatous Germ Cell Tumor.

Objective: To evaluate the oncologic outcomes and histologic concordance of postchemotherapy residual liver mass resection with postchemotherapy retroperitoneal lymph node dissection (PC-RPLND).

Methods: Retrospective review of our prospectively maintained germ cell tumor (GCT) surgical database identified patients with nonseminomatous GCT who underwent both postchemotherapy residual liver mass resection and PC-RPLND between 1990 and 2015.

Results: A total of 36 patients were identified, of whom 29 (81%) presented with a liver mass at initial diagnosis and 17 (47%) received second-line chemotherapy before liver resection. Teratoma was found in 8 (22%) and 5 (14%) of PC-RPLND and liver resection specimens, respectively. Viable GCT was found in 5 (14%) and 4 (11%) of PC-RPLND and liver resection specimens, respectively. Histologic discordance was observed in 4 of 19 patients (21%; 95% confidence interval [CI] 6.1%-46%); in all cases, liver resection specimens contained teratoma or viable GCT while PC-RPLND revealed only fibrosis or necrosis. At 3 years after surgical intervention, the Kaplan-Meier estimated probability of cancer-specific survival was 75% (95% CI 55%-85%) and the probability of progression-free survival was 75% (95% CI 56%-87%).

Conclusion: In this contemporary cohort, clinically significant discordance was observed between the histology of metastatic liver masses and that of retroperitoneal lymph nodes. The benefit of postchemotherapy liver mass resection for patients with advanced nonseminomatous GCT is supported by favorable survival outcomes. Until more reliable predictors of postchemotherapy histology exist, complete surgical resection of all sites of residual disease should be performed whenever feasible.