Survival Benefit of Primary Tumor Resection Among Elderly Patients with Pancreatic Neuroendocrine Tumors.

Abstract

Pancreatectomy is the main curative therapeutic option for pancreatic neuroendocrine tumors (pNETs). Given the indolent behavior of pNETs and the relatively limited lifetime of elderly patients, the impact of primary site surgery (PSS) of pNETs on long-term outcomes among older patients has been a topic of debate. Patients aged 70 or older with pNETs were identified in the Surveillance, Epidemiology and the End Results (SEER) database from 1998 to 2016. Propensity score matching was used to compare overall (OS) and cancer-specific survival (CSS) of patients who did versus did not undergo PSS. Among 2,319 elderly patients with pNETs, 942 patients (40.6%) underwent PSS, while 1,377 (59.4%) did not undergo PSS (non-PSS: NPSS). After propensity score matching (n = 433 in each group), PSS group had improved survival compared with the NPSS group (5-year OS: 53.4% vs. 37.3%; 5-year CSS: 77.2% vs. 58.1%, both p < 0.001). In contrast, subgroup analysis of individuals aged ≥ 80 revealed no difference in 5-year CSS (PSS: 69.2% vs. NPSS: 67.4%, p = 0.27). A subgroup analysis among patients who had small (≤ 2cm) non-functional (NF) pNETs noted comparable long-term outcomes among patients who underwent PSS versus NPSS patients (5-year OS: 73.1% vs. 66.5%, p = 0.19; 5-year CSS: 98.5% vs. 95.2%, p = 0.14). Approximately 2 in 5 elderly patients with pNETs underwent PSS. While PSS was generally associated with prolonged OS and CSS among older patients, PSS was not associated with improved CSS among a subset of patients aged 80 or older, as well as among patients age ≥ 70years with NF-pNET less than 2cm.