title: Surveillance strategy for rectal neuroendocrine tumors according to recurrence risk stratification.
abstract: OBJECTIVE
  Rectal neuroendocrine tumors (NETs) have been increasing in incidence. However, the recommendations for disease surveillance after tumor resection have not been well established. We evaluated the long-term outcomes of rectal NETs and surveillance strategies according to recurrence risk stratification.
  
  
  METHODS
  From January 2000 to July 2011, 188 patients diagnosed with rectal NETs were included in this study. Patient characteristics, treatment methods, recurrence rates, risk factors of recurrence, and surveillance schedules were analyzed.
  
  
  RESULTS
  The male-to-female ratio was 1.29:1 and the mean age at diagnosis was 50.6 years. The mean tumor size was 6.5 (range 1-30) mm. A total of 144 patients (76.6 %) were treated with endoscopic resection, and 44 patients (23.4 %) were treated with surgical resection as the initial treatment. During the follow-up period, ten patients (5.3 %) had disease recurrence, including one case of local recurrence and nine cases of recurrence at a distant site. Tumor size of >10 mm, invasion of the muscularis propria, increased mitotic index, lymphovascular invasion, and regional lymph node metastases were statistically significant predictors of recurrence by univariate analysis. Among the 152 patients without risk factors of recurrence, only one patient who underwent transanal resection had a local recurrence at 15 months after surgery.
  
  
  CONCLUSIONS
  Our patients with rectal NETs showed favorable clinical outcomes and had a low rate of recurrence. Intensive surveillance with endoscopy or imaging study may not be required in patients without risk factors for recurrence.
authors: Department of Internal Medicine, Institute of Gastroenterology, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, South Korea.
authors: Dong Hyun
authors: DH
authors: Kim
authors: Jin Ha
authors: JH
authors: Lee
authors: Yoon Jin
authors: YJ
authors: Cha
authors: Soo Jung
authors: SJ
authors: Park
authors: Jae Hee
authors: JH
authors: Cheon
authors: Tae Il
authors: TI
authors: Kim
authors: Hoguen
authors: H
authors: Kim
authors: Won Ho
authors: WH
authors: Kim
authors: Sung Pil
authors: SP
authors: Hong
mesh_terms: D000328:Adult; D000368:Aged; D018278:Carcinoma, Neuroendocrine / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D003113:Colonoscopy; D003266:Continuity of Patient Care; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D011159:Population Surveillance / Q000379:methods; D011379:Prognosis; D012004:Rectal Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000601:surgery; D018570:Risk Assessment; D012307:Risk Factors