title: Assessing the role of primary tumour resection in patients with synchronous unresectable liver metastases from pancreatic neuroendocrine tumour of the body and tail. A propensity score survival evaluation.
abstract: BACKGROUND
  The role of primary tumour surgery in pancreatic neuroendocrine tumours (PNETs) with unresectable liver metastases is controversial and international guidelines do not recommend surgery in such cases. Resectability of the primary tumour has never been considered in outcome comparisons between operated and non-operated patients.
  
  
  METHODS
  From two institutional prospective databases of patients affected by PNET and unresectable liver metastases, 63 patients who underwent a left-pancreatectomy at diagnosis were identified and compared with a group of 30 patients with a potentially resectable but not-resected primary tumour located in the body or tail. The endpoint was overall survival (OS).
  
  
  RESULTS
  The two groups significantly differed at baseline with regard to liver tumour burden Ki-67 labelling index, site of pancreas, results of the18FDG PET-CT and age. In the operated patients, surgical morbidity comprised 7 cases of pancreatic fistula. Postoperative mortality was nil. Median OS for patients undergoing left-pancreatectomy was 111 months vs 52 for the non operated patients (p = 0.003). At multivariate analysis after propensity score adjustment, no surgery as well as liver tumour burden>25% and higher Ki-67 index were associated with an increased risk of death during follow-up. In patients with unresectable primary tumour, OS was similar in comparison to that in the resectable but non-resected patients, and significantly worse than that in the resected patients (p = 0.032).
  
  
  CONCLUSIONS
  In PNETs located in the body or tail and diffuse liver metastases distal pancreatectomy may be justified in selected patients. Randomized studies may be safely proposed in future on this topic.
authors.affiliation: Division of Hepatobilio-Pancreatic Surgery, European Institute of Oncology, Italy. Electronic address: emilio.bertani@ieo.it.
authors.forename: E
authors.initials: E
authors.lastname: Bertani
authors.affiliation: Gastrointestinal Medical Oncology and Neuroendocrine Tumours Unit, European Institute of Oncology, Milano, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Fazio
authors.affiliation: Division of Epidemiology and Biostatistics, European Institute of Oncology, Milano, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Radice
authors.affiliation: Department of Surgery, Ospedale Sacro Cuore Don Calabria, Negrar, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Zardini
authors.affiliation: Division of Hepatobilio-Pancreatic Surgery, European Institute of Oncology, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Spinoglio
authors.affiliation: Division of Digestive Surgery, European Institute of Oncology, Università Statale di Milano, Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Chiappa
authors.affiliation: Division of Hepatobilio-Pancreatic Surgery, European Institute of Oncology, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Ribero
authors.affiliation: Division of Digestive Surgery, European Institute of Oncology, Università Statale di Milano, Milano, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Biffi
authors.affiliation: Division of Pancreatic Surgery, Ospedale San Raffaele IRCCS, Università Vita e Salute, Milano, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Partelli
authors.affiliation: Division of Pancreatic Surgery, Ospedale San Raffaele IRCCS, Università Vita e Salute, Milano, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Falconi
mesh_terms: D005260:Female; D006801:Humans; D007558:Italy; D008113:Liver Neoplasms / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000601:surgery; D018358:Neuroendocrine Tumors / Q000556:secondary* / Q000601:surgery*; D010180:Pancreatectomy; D010190:Pancreatic Neoplasms / Q000473:pathology* / Q000601:surgery*; D057216:Propensity Score; D011446:Prospective Studies; D012042:Registries; D015996:Survival Rate; D016896:Treatment Outcome
keywords: Pancreatic neuroendocrine tumours; Prognostic factors; Resection; Survival; Synchronous liver metastases