title: Tumour diameter is a predictor of mesorectal and mesenteric lymph node metastases in anorectal melanoma.
abstract: OBJECTIVE
  Anorectal melanoma is a rare neoplasm with poor prognosis. The aim of this study was to investigate what clinicopathological factors predict lymph node metastases and to investigate their association with survival.
  
  
  METHODS
  Patients undergoing surgery with curative intent for primary anorectal melanoma in Fudan University Shanghai Cancer Center between 1989 and 2011 were studied retrospectively. The associations between clinicopathological factors and lymph node metastases and prognosis were determined.
  
  
  RESULTS
  Forty-three patients underwent a potentially curative resection with a median follow-up of 20 months; the 5-year overall survival rate was 29.6% with median overall survival of 28 months. Tumour diameter > 3 cm was associated with mesorectal and mesenteric lymph node metastases (P = 0.013). Perineural invasion (hazard ratio 5.683; 95% CI 1.978-16.328; P = 0.001) was the only factor that independently predicted survival.
  
  
  CONCLUSIONS
  Tumour diameter was associated with mesorectal and mesenteric lymph node metastases; therefore, wide local excision may not be appropriate for surgery with curative intent for patients with a tumour diameter ≥ 3 cm. Perineural invasion was an important prognostic factor for anorectal melanoma.
authors.affiliation: Department of Colorectal Surgery, Cancer Hospital, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: M
authors.initials: M
authors.lastname: Wang
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: J
authors.initials: J
authors.lastname: Zhu
authors.forename: W
authors.initials: W
authors.lastname: Sheng
authors.forename: P
authors.initials: P
authors.lastname: Lian
authors.forename: F
authors.initials: F
authors.lastname: Liu
authors.forename: S
authors.initials: S
authors.lastname: Cai
authors.forename: Y
authors.initials: Y
authors.lastname: Xu
mesh_terms: D000328:Adult; D000368:Aged; D001005:Anus Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D008643:Mesentery; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies
keywords: Anorectal melanoma; lymph node metastases; prognosis; surgery