Palliative Resection of Primary Tumor in Metastatic Nonfunctioning Pancreatic Neuroendocrine Tumors.

BACKGROUND: Whether primary tumor resection is beneficial in patients with metastatic nonfunctioning pancreatic neuroendocrine tumors (NF-pNETs) remains unclear. This study aimed to investigate whether palliative resection of primary tumor affected the survival of patients with stage IV NF-pNETs. METHODS: We collected data from patients with stage IV NF-pNET registered in the Surveillance, Epidemiology, and End Results database from 2004 to 2015. Risk-adjusted Cox proportional hazard regression analysis and propensity score-matched analysis were used to analyze overall survival (OS) and cancer-specific survival (CSS) of patients. RESULTS: In total, 1974 stage IV NF-pNETs patients were identified, of whom 392 (19.9%) received palliative primary tumor resection. The latter exhibited significantly prolonged OS (hazard ratio = 2.514, 95% confidence interval: 2.081-3.037, P < 0.001) and CSS (hazard ratio = 2.634, 95% confidence interval: 2.159-3.213, P < 0.001) in multivariate Cox regression analysis. According to propensity score-matched results, patients without primary tumor resection had worse OS and CSS. CONCLUSIONS: This study demonstrates that there is a significant correlation between palliative resection of primary tumor and survival benefit. Therefore, resection could be considered as an additional treatment option in this specific patient population.