title: The survival outcome and prognostic factors for distal cholangiocarcinoma following surgical resection: a meta-analysis for the 5-year survival.
abstract: OBJECTIVE
  To assess the available evidence on the prognostic factors for the 5-year survival for patients with distal cholangiocarcinoma (DCC) following surgical resection.
  
  
  METHODS
  We performed a comprehensive search of abstracts included in databases where relevant studies were published between January 2000 and August 2015. Risk ratios (RRs), 95 % confidence intervals (95 % CIs), and random-effects model were calculated using RevMan 5.3 software.
  
  
  RESULTS
  A total of 23 observational studies involving 2063 patients with DCC were analyzed. The meta-analysis showed that postoperative adjuvant chemotherapy was not confirmed as a prognostic factor, with similar 5-year survival rates between those receiving and not receiving chemotherapy (RR 0.71; 95 % CI 0.21-2.36; P = 0.57). Perineural invasion (RR 0.51; 95 % CI 0.40-0.64; P < 0.00001), lymph node metastasis (RR 0.51; 95 % CI 0.38-0.70; P < 0.0001), positive resection margin status (RR 2.11; 95 % CI 1.36-3.30; P = 0.001), and not-well-differentiated adenocarcinoma (RR 1.77; 95 % CI 1.39-2.25; P < 0.00001) were associated with shorter survival.
  
  
  CONCLUSIONS
  Perineural invasion, lymph node metastasis, resection margin status, and tumor differentiation were the significant prognostic factors for the 5-year survival.
authors.affiliation: Clinic for Surgery, UKSH Campus Lübeck, Lübeck, Germany.
authors.forename: U F
authors.initials: UF
authors.lastname: Wellner
authors.affiliation: Department of Surgery, Hubei Hospital of Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, 430061, People's Republic of China. dfydzsjd@126.com.
authors.forename: YinFeng
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Clinic for Surgery, UKSH Campus Lübeck, Lübeck, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Keck
authors.affiliation: Department of Surgery, Hubei Hospital of Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, 430061, People's Republic of China.
authors.forename: WenYin
authors.initials: W
authors.lastname: Jin
authors.affiliation: Department of Surgery, Hubei Hospital of Chinese Medicine, Hubei University of Chinese Medicine, Wuhan, 430061, People's Republic of China.
authors.forename: Ze
authors.initials: Z
authors.lastname: Xu
mesh_terms: D000368:Aged; D001650:Bile Duct Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D017024:Chemotherapy, Adjuvant; D018281:Cholangiocarcinoma / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D000072662:Margins of Excision; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009380:Neoplasms, Nerve Tissue / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome
keywords: Distal cholangiocarcinoma; Meta-analysis; Prognostic factors