Minimally Invasive Versus Open Treatment for Benign Sporadic Insulinoma Comparison of Short-Term and Long-Term Outcomes.

BACKGROUND: Benign insulinoma is the most common functioning neuroendocrine tumor of the pancreas, and its incidence is estimated at 0.4%. The treatment of choice is organ-preserving resection. The aim of this study was to compare short-term and long-term outcomes of minimally invasive laparoscopic or robotic enucleation (MIC-EN) and open enucleation (O-EN) for sporadic benign insulinoma. METHODS: A retrospective bi-institutional analysis of 71 patients who underwent an enucleation for sporadic benign insulinoma between 2003 and 2016 was performed. Patients were analyzed according to intention-to-treat principle. RESULTS: Fifteen (21%) patients underwent MIC-EN (three robotic and 12 laparoscopic) and 56 (79%) patients O-EN. In all MIC-EN patients, the insulinoma was localized by preoperative imaging compared to only 62.5% (35 of 56) patients in the O-EN group (p = 0.005). Three of the MIC-EN patients (20%) with insulinomas in the pancreatic head had to undergo a conversion. Excluding conversions, MIC-EN procedures were shorter (145 vs 180, p = 0.036) compared to O-EN surgery. Late complications and pathological data did not differ between groups, excluding margin status R1 MIC-EN (26.7%) compared to O-EN (10.7%, p = 0.115). After a median follow-up of 75 (range 1-151) months, all patients were alive, but four (5.6%) patients (one after MIC-EN and three after O-EN) developed a functional recurrence. No patient with a R1 resection had a disease recurrence. CONCLUSIONS: MIC-EN for benign sporadic insulinoma is a safe procedure with at least similar short-term and long-term postoperative outcomes as the open technique. Thus, preoperatively localized benign insulinoma should be approached laparoscopically, if technically feasible.