Impact of delay in surgery after diagnosis of pancreatic neuroendocrine tumors: Should you rush to operate?

Background

Current guidelines for the management of pancreatic neuroendocrine tumors consider observation of localized pancreatic neuroendocrine tumors <1 cm, but it remains unclear if larger tumors have a propensity to spread. We aimed to assess the safety of delayed surgery on larger tumors and determine candidacy of a clinically relevant subgroup for nonoperative management.

Methods

Resected M0, T1 (<2 cm), T2 (2-4 cm), and T3 (>4 cm) pancreatic neuroendocrine tumors from the Surveillance, Epidemiology, and End Results program from 2010 to 2022 were included. The interval from diagnosis to surgery and disease-specific survival were analyzed. National Cancer Database patients were then reviewed to assess the effect of surgical delay on incidence of pathologic upstaging and overall survival.

Results

Overall, 4,898 and 9,072 patients from the Surveillance, Epidemiology, and End Results program and the National Cancer Database were included, respectively. Multivariable analysis demonstrated no impact of 3- to 6-month or 6- to 12-month delay to surgery on disease-specific survival (P = .44, .74) or overall survival (P = .51, .39). Subgroup analysis of T2, G1 nonfunctional tumors (Surveillance, Epidemiology, and End Results, n = 988; National Cancer Database, n = 1,645) demonstrated no difference in disease-specific survival (P = .28, .23), overall survival (P = .97, .77), or odds of upstaging (P = .41, .09) with delay to surgery. T2 subgroup patients undergoing nonoperative management (National Cancer Database, n = 350) demonstrated decreased overall survival when compared with surgical treatment on multivariate analysis (hazard ratio, 2.32; 95% confidence interval, 1.55-3.48; P < .01).

Conclusion

Delayed surgery is safe for localized pancreatic neuroendocrine tumors without evidence of metastasis, and necessary time should be taken after diagnosis to optimize modifiable risk factors that impact survival. Expanding nonoperative management to patients with tumors >2 cm should be approached cautiously due to the association of nonoperative management with worse overall survival.