title: Laparoscopic surgical exploration is an effective strategy for locating occult primary neuroendocrine tumors.
abstract: BACKGROUND
  Many patients with neuroendocrine tumors (NETs) have metastases at diagnosis. Despite extensive metastases the primary tumors remain small and difficult to locate.
  
  
  METHODS
  Records of patients diagnosed with metastatic abdominal NETs from 2006 to 2010 were reviewed retrospectively. Results of preoperative imaging, procedures, and surgical explorations were compared for their efficacy at finding primary tumors.
  
  
  RESULTS
  Sixty-three patients were identified. Seventeen percent (11 of 63) of tumors were located by preoperative testing. The sensitivities of preoperative colonoscopy (23% [n = 26]), computed tomography scan (6.7% [n = 60]), and somatostatin receptor scintigraphy (2.0% [n = 52]) were low. No tumors were found by magnetic resonance imaging (n = 9), upper endoscopy (n = 24), capsule endoscopy (n = 2), or bronchoscopy (n = 4). Surgical exploration was the most sensitive (79% [n = 63]) method of tumor detection. Seventy-two percent of surgical localizations were laparoscopic.
  
  
  CONCLUSIONS
  Surgical exploration was superior to all other modalities for locating primary NETs. Laparoscopy had a high probability of finding occult primary neuroendocrine tumors.
authors.affiliation: Division of General Surgery, Department of Surgery, Oregon Health and Science University, Portland, OR, USA.
authors.forename: Kristen P
authors.initials: KP
authors.lastname: Massimino
authors.affiliation: Division of General Surgery, Department of Surgery, Oregon Health and Science University, Portland, OR, USA.
authors.forename: Esther
authors.initials: E
authors.lastname: Han
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Oregon Health and Science University, Mail Code L619, 3181 SW Sam Jackson Park Rd., Portland, OR 97239, USA.
authors.forename: SuEllen J
authors.initials: SJ
authors.lastname: Pommier
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Oregon Health and Science University, Mail Code L619, 3181 SW Sam Jackson Park Rd., Portland, OR 97239, USA. Electronic address: pommierr@ohsu.edu.
authors.forename: Rodney F
authors.initials: RF
authors.lastname: Pommier
mesh_terms: D005260:Female; D006801:Humans; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009382:Neoplasms, Unknown Primary / Q000175:diagnosis*; D018358:Neuroendocrine Tumors / Q000175:diagnosis*; D012189:Retrospective Studies