Similar Outcomes in Minimally Invasive versus Open Management of Primary Pancreatic Neuroendocrine Tumors: A Regional, Multi-Institutional Collaborative Analysis

SIMPLE SUMMARY: Pancreatic neuroendocrine tumors (PNETs) are rare tumors of the pancreas that are often curable with surgery. Due to their rarity, it is difficult to study whether newer techniques for removing PNETs, specifically minimally invasive surgeries, are as safe and effective as open surgeries in these patients. In this study, we pooled the experience of multiple high-volume institutions who remove PNETs, and studied outcomes in open and minimally invasive surgeries. We discovered that patients receiving a minimally invasive surgery were equally likely to remain alive and without disease as patients receiving an open surgery. Additionally, there was no difference in the most common complications experienced by patients receiving these operations. Therefore, we can recommend the routine use of minimally invasive surgery techniques in appropriately selected patients with PNET, if offered by their surgeon. ABSTRACT: In pancreatic neuroendocrine tumors (PNETs), the impact of minimally invasive (MI) versus open resection on outcomes remains poorly studied. We queried a multi-institutional pancreatic cancer registry for patients with resected non-metastatic PNET from 1996–2020. Recurrence-free (RFS), disease-specific survival (DSS), and operative complications were evaluated. Two hundred and eighty-two patients were identified. Operations were open in 139 (49%) and MI in 143 (51%). Pancreaticoduodenectomy was performed in 77 (27%, n = 23 MI), distal pancreatectomy in 184 (65%, n = 109 MI), enucleation in 13 (5%), and total pancreatectomy in eight (3%). Median follow-up was 50 months. Thirty-six recurrences and 13 deaths from recurrent disease yielded 5-year RFS and DSS of 85% and 95%, respectively. On multivariable analysis, grade 1 (HR 0.07, p < 0.001) and grade 2 (HR 0.20, p = 0.002) tumors were associated with improved RFS, while T3/T4 tumors were associated with worse RFS (OR 2.78, p = 0.04). MI resection was not associated with RFS (HR 0.53, p = 0.14). There was insufficient mortality to evaluate DSS with multivariable analysis. Of 159 patients with available NSQIP data, incisional surgical site infections (SSIs), organ space SSIs, Grade B/C pancreatic fistulas, reoperations, and need for percutaneous drainage did not differ by operative approach (all p > 0.2). Nodal harvest was similar for MI versus open distal pancreatectomies (p = 0.16) and pancreaticoduodenectomies (p = 0.28). Minimally invasive surgical management of PNETs is equivalent for oncologic and postoperative outcomes.