title: Assessing the short- and long-term outcomes after resection of benign insulinoma.
abstract: BACKGROUND
  Insulinoma is a rare functional pancreatic neuroendocrine tumour (NET) believed to have an excellent long-term outcome, but few studies have solely focused on this issue after apparently curative resection. This study aimed to assess post-operative and long-term outcomes after resection of benign insulinomas.
  
  
  METHODS
  From 1998 to 2013, 36 consecutive patients with insulinomas underwent surgery. Three patients had multiple endocrine neoplasia type-1 (MEN-1). Demographics, operative findings, tumour grade (2010 World Health Organization (WHO) NET classification), post-operative pancreatic fistula (POPF) grade (International Study Group of Pancreatic Fistula (ISGPF)), complications and recurrence were analysed.
  
  
  RESULTS
  Eighteen (50%) had enucleation while the rest underwent pancreatic resection. The majority (86.1%) of insulinomas belonged to WHO NET grade G1. POPF occurred in 58.3% of patients while clinical fistula (ISGPF grades B and C) occurred in 19.4%. One (2.8%) patient required reoperation. The occurrence of POPF was not related to type of resection or surgical approach. There was no perioperative mortality. After a mean follow-up of 83.6 months, two patients (5.7%) developed disease recurrence at 34.4 and 131.9 months after initial surgery. No patients developed distant metastasis. The 10- and 15-year disease-free rates were 95.6 and 85.4%, respectively.
  
  
  CONCLUSIONS
  POPF occurred frequently and posed a significant morbidity after resection of insulinoma. However, it occurred independently of type of resection or surgical approach. Although the immediate cure rate after resection was high (100%), long-term disease recurrence in sporadic (non-MEN-1) cases was not insignificant. Regular long-term follow-up is recommended.
authors.affiliation: Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong, Hong Kong.
authors.forename: Yi-Po
authors.initials: YP
authors.lastname: Tsang
authors.affiliation: Division of Endocrine Surgery, Department of Surgery, The University of Hong Kong, Hong Kong.
authors.forename: Brian Hung-Hin
authors.initials: BH
authors.lastname: Lang
authors.affiliation: Department of Pathology, The University of Hong Kong, Hong Kong.
authors.forename: Tony Wai-Hung
authors.initials: TW
authors.lastname: Shek
mesh_terms: D019160:Endosonography; D005260:Female; D005500:Follow-Up Studies; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007340:Insulinoma / Q000175:diagnosis / Q000601:surgery*; D010535:Laparoscopy / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010180:Pancreatectomy / Q000379:methods*; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: enucleation; insulinoma; pancreatectomy; pancreatic fistula; recurrence