title: Survival outcomes and surgical intervention of small intestinal neuroendocrine tumors: a population based retrospective study.
abstract: BACKGROUND
  Small intestinal neuroendocrine tumors (SiNETs) without distant metastasis typically behave in an indolent manner, but there can be heterogeneity. We aimed to define the survival outcomes and impacts of surgical intervention.
  
  
  METHODS
  A retrospective cohort study was conducted by using data from the Surveillance, Epidemiology, and End Results (SEER) database. Clinicopathologic features were analyzed in 4407 patients between 2000 and 2012. The cancer specific survival (CSS) was calculated by the Kaplan-Meier method. Multivariable Cox regression models with hazard ratios (HRs) were constructed to analyze survival outcomes and risk factors.
  
  
  RESULTS
  The adjusted incidence of early SiNETs is 1.3/100,000. Tumors are most commonly located in the ileum and are small (≤ 2 cm). The 5-year and 10-year CSS rates were 95.0% and 88.5%, respectively. Age > 50 years, large tumor size (> 2cm), poor differentiation, advanced T classification, and absence of surgical treatment were independent predictors of poor survival. Stratified analysis indicated that surgery significantly improved survival in patients that were white (HR, 0.45), > 50 years old (HR, 0.61), had duodenal tumors (HR, 0.43), large tumors (> 2cm) (HR, 0.32), advanced T classification (T3: HR, 0.29; T4: HR, 0.18) or well differentiation (HR, 0.55). There was no significant survival difference between local resection and radical resection (P =0.884).
  
  
  CONCLUSIONS
  Early SiNETs have a favorable prognosis. Surgical resection may improve outcomes, particularly in older patients and those with large tumors. More aggressive resections couldn't improve outcomes.
authors.affiliation: Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.|Institution of Gastroenterology, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Lunpo
authors.initials: L
authors.lastname: Wu
authors.affiliation: Department of Oncology, Zhejiang University Jinhua Hospital, Jinhua, Zhejiang Province, China.
authors.forename: Jianfei
authors.initials: J
authors.lastname: Fu
authors.affiliation: Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.|Institution of Gastroenterology, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wan
authors.affiliation: Department of Endocrinology, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Pan
authors.affiliation: Institution of Gastroenterology, Zhejiang University, Hangzhou, Zhejiang Province, China.|Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Sanchuan
authors.initials: S
authors.lastname: Lai
authors.affiliation: Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.|Institution of Gastroenterology, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhong
authors.affiliation: Gastrointestinal Unit, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Chung
authors.affiliation: Department of Gastroenterology, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang Province, China.|Institution of Gastroenterology, Zhejiang University, Hangzhou, Zhejiang Province, China.
authors.forename: Liangjing
authors.initials: L
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D013505:Digestive System Surgical Procedures; D005260:Female; D006801:Humans; D007414:Intestinal Neoplasms / Q000473:pathology / Q000601:surgery*; D007421:Intestine, Small / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000473:pathology / Q000601:surgery*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018426:SEER Program; D016019:Survival Analysis; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: SEER; neuroendocrine tumors; prognostic factors; small intestine; surgical management