title: Oral anticoagulation may prolong survival of a subgroup of patients with cancer: a cochrane systematic review.
abstract: To evaluate the effectiveness and safety of oral anticoagulants in improving survival of cancer patients. We conducted in January 2007 a comprehensive search for relevant randomized clinical trials (RCTs). We extracted data on methodological quality, participants, interventions and outcomes using a standardized form. Five RCTs fulfilled the inclusion criteria and all compared warfarin to either placebo or no intervention. Their overall methodological quality was acceptable. The effect of warfarin on mortality was not statistically significant at 6 months (RR = 0.96; 95% CI 0.80-1.16), at 1 year (RR = 0.95; 95% CI 0.86-1.05), at 2 years (RR = 0.97; 95% CI 0.87-1.08) or at 5 years (RR 0.91; 95% CI 0.83-1.01). In the subgroup of patients with small cell lung cancer (SCLC), warfarin reduced mortality at 6 months (RR = 0.69; 95% CI 0.50-0.96) but not at 1 year (RR = 0.88; 95% CI 0.77-1.01). This 6 months mortality benefit was statistically significant in the subgroup of extensive SCLC (RR = 0.65; 95% CI 0.45-0.93) but not in the subgroup of limited SCLC (RR = 0.68; 95% CI 0.36-1.28). Warfarin increased both major bleeding (RR = 4.24; 95% CI 1.85-9.68) and minor bleeding (RR = 3.34; 95% CI 1.66-6.74). The evidence suggests a survival benefit from warfarin in patients with extensive SCLC, but not in other patient groups. This survival benefit should be weighed against the increased risk for hemorrhage.
authors.affiliation: Department of Medicine, State University of New York at Buffalo, NY 14215, USA. elieakl@buffalo.edu
authors.forename: E A
authors.initials: EA
authors.lastname: Akl
authors.forename: G
authors.initials: G
authors.lastname: Kamath
authors.forename: S Y
authors.initials: SY
authors.lastname: Kim
authors.forename: V
authors.initials: V
authors.lastname: Yosuico
authors.forename: M
authors.initials: M
authors.lastname: Barba
authors.forename: I
authors.initials: I
authors.lastname: Terrenato
authors.forename: F
authors.initials: F
authors.lastname: Sperati
authors.forename: H J
authors.initials: HJ
authors.lastname: Schünemann
mesh_terms: D000284:Administration, Oral; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D018288:Carcinoma, Small Cell / Q000188:drug therapy / Q000401:mortality; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000401:mortality; D009369:Neoplasms / Q000188:drug therapy* / Q000401:mortality*; D016032:Randomized Controlled Trials as Topic; D016019:Survival Analysis; D014859:Warfarin / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D000925:Anticoagulants; D014859:Warfarin