Minimally Invasive Versus Open Pancreatectomy for Right-Sided and Left-Sided G1/G2 Nonfunctioning Pancreatic Neuroendocrine Tumors: A Multicenter Matched Analysis with an Inverse Probability of Treatment-Weighting Method

Abstract

Background Limited evidence exists for the safety and oncologic efficacy of minimally invasive surgery (MIS) for nonfunctioning pancreatic neuroendocrine tumors (NF-PNETs) according to tumor location. This study aimed to compare the surgical outcomes of MIS and open surgery (OS) for right- or left-sided NF-PNETs. Methods The study collected data on patients who underwent surgical resection (pancreatoduodenectomy, distal/total/central pancreatectomy, duodenum-preserving pancreas head resection, or enucleation) of a localized NF-PNET between January 2000 and July 2017 at 14 institutions. The inverse probability of treatment-weighting method with propensity scores was used for analysis. Results The study enrolled 859 patients: 478 OS and 381 MIS patients. A matched analysis by tumor location showed no differences in resection margin, intraoperative blood loss, or complications between MIS and OS. However, MIS was associated with a longer operation time for right-sided tumors (393.3 vs 316.7 min; P < 0.001) and a shorter postoperative hospital stay for left-sided tumors (8.9 vs 12.9 days; P < 0.01). The MIS group was associated with significantly higher survival rates than the OS group for right- and left-sided tumors, but survival did not differ for the patients divided by tumor grade and location. Multivariable analysis showed that MIS did not affect survival for any tumor location. Conclusion The short-term outcomes offered by MIS were comparable with those of OS except for a longer operation time for right-sided NF-PNETs. The oncologic outcomes were not compromised by MIS regardless of tumor location or grade. These findings suggest that MIS can be performed safely for selected patients with localized NF-PNETs.