title: Clinicopathologic characteristics of pancreatic neuroendocrine tumors and relation of somatostatin receptor type 2A to outcomes.
abstract: BACKGROUND
  The impact of somatostatin receptor type 2 (SSTR-2a) expression levels on outcomes in patients with pancreatic neuroendocrine tumors (PNETs) has not been evaluated.
  
  
  METHODS
  Correlations between clinicopathologic characteristics, including SSTR-2a expression and outcomes, were retrospectively studied in 79 patients with pancreatic neuroendocrine tumors (PNETs).
  
  
  RESULTS
  The SSTR-2a score was 0 in 27% of patients, 1 in 24% of patients, 3 in 30% of patients, and 4 in 18% of patients. The overall survival rate was 87% at 1 year, 77% at 3 years, and 71% at 5 years. On univariate analysis, a pancreatic tumor that measured ≥ 20 mm in greatest dimension, stage IV disease, vascular invasion, neuroendocrine carcinoma (NEC), and an SSTR-2a score of 0 were associated significantly with poor outcomes. On multivariate analysis, NEC (P = .000; hazard ratio, 28.8; 95% confidence interval, 7.502-111.240) and an SSTR-2a score of 0 (P = .001; hazard ratio, 3.611; 95% confidence interval, 1.344-9.702) were related independently to poor outcomes.
  
  
  CONCLUSIONS
  The current analysis of prognostic factors in patients with PNETs demonstrated that NEC and an SSTR-2a score of 0 both were significant independent predictors of poor outcomes. The results suggest that the assessment of SSTR-2a may facilitate the selection of treatment regimens and the prediction of outcomes. Because a considerable proportion of patients with NEC have SSTR-2a-positive tumors, further analyses of the usefulness of somatostatin analogues are warranted in patients who have SSTR-2a-positive NEC.
authors.affiliation: Department of Gastroenterology, Kitasato University East Hospital, Kanagawa, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Okuwaki
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kida
authors.forename: Tetuo
authors.initials: T
authors.lastname: Mikami
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamauchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imaizumi
authors.forename: Shiro
authors.initials: S
authors.lastname: Miyazawa
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Iwai
authors.forename: Miyoko
authors.initials: M
authors.lastname: Takezawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Saegusa
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Wasaburo
authors.initials: W
authors.lastname: Koizumi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D018358:Neuroendocrine Tumors / Q000737:chemistry / Q000401:mortality / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000737:chemistry / Q000401:mortality / Q000473:pathology*; D011379:Prognosis; D017481:Receptors, Somatostatin / Q000032:analysis*; D012189:Retrospective Studies
chemical_list: D017481:Receptors, Somatostatin; C093733:somatostatin receptor 2
keywords: 2010 World Health Organization classification; SSTR-2a; neuroendocrine tumor; pancreatic neuroendocrine tumors; somatostatin receptor type 2A