Survival effect of complete surgical resection of the primary tumor in patients with metastatic, high-risk neuroblastoma in a large Canadian cohort

PurposeTo determine whether extent of surgical resection of the primary tumor correlates with survival in patients with International Neuroblastoma Staging System (INSS) stage 4, high-risk neuroblastoma. MethodsData were extracted for patients with newly diagnosed INSS stage 4, high-risk neuroblastoma between 2001 and 2019 from the national Cancer in Young People in Canada (CYPC) database. Complete resection was defined as gross total resection of primary tumor based on operative reports. Primary endpoints were 3 and 5-year event-free (EFS) and overall survival (OS). Survival analyses were completed using log-rank test and Cox proportional hazards regression including covariates of age, sex, decade of treatment (2001-2009 vs. 2010-2019), immunotherapy, and tandem stem cell transplant (SCT). ResultsOne-hundred and forty patients with complete surgical data were included. On univariate analysis, 3-year EFS and OS for patients that had complete versus incomplete resection was 71% (95% CI 57-80%) vs. 48% (36-60%) and 86% (75-93%) vs. 64% (51-74%), p = .008 and p = .002, respectively. 5-year EFS and OS for patients with complete resection also demonstrated significantly improved survival. On Cox Proportional Hazards models adjusted for age, immunotherapy, tandem SCT, and surgical resection, only complete resection was associated with statistically significant improved 3 year EFS and OS, HR = 0.48 (0.29-0.81; p = .006) and HR = 0.42 (0.24-0.73; p = .002). ConclusionsIn a large Canadian INSS stage 4 high-risk neuroblastoma cohort, complete surgical resection was associated with increased EFS and OS. Within the constraints of a retrospective study, these results suggest that the ability to achieve primary tumor complete resection in patients with metastatic high-risk disease is associated with improved survival.