Oncological outcomes following left-sided pancreatic resection for grade 1 and grade 2 pancreatic neuroendocrine tumours: a population-cohort study comparing open with minimally-invasive surgery

BACKGROUND: Minimally invasive left-sided pancreatectomy (MIS-LP) is increasingly adopted for resection of grade 1 and 2 pancreatic neuroendocrine tumours (PNETs), but its oncological equivalence to open left-sided pancreatectomy (O-LP) remains to be fully evaluated. METHODS: We conducted a retrospective cohort study using SEER-Medicare data (2010-2019) including all patients who underwent left-sided pancreatectomy (LP) for PNETs. A multilevel Cox regression model was used to to provide adjusted hazard ratios (HR) for overall survival (OS) and cancer-specific survival (CSS) when comparing between MIS-LP and O-LP. A 6-month landmark survival analysis was performed to account for early postoperative deaths. RESULTS: A total of 772 patients were included, with 257 (33.3%) undergoing MIS-LP. Six-hundred-and-seventy-two patients had grade 1, and 100 patients had grade 2 PNETs. MIS-LP was associated with better OS (HR 0.48, 95% CI 0.26-0.86, P=0.014) and CSS (HR 0.35, 95% CI 0.14-0.88, P=0.026). In the 6-month landmark analysis, O-LP was associated with similar OS and CSS to MIS-LP. CONCLUSION: MIS-LP is associated with improved early survival compared to O-LP in patients with low- to intermediate-grade PNETs.