title: Use of aspirin postdiagnosis improves survival for colon cancer patients.
abstract: BACKGROUND
  The preventive role of non-steroid anti-inflammatory drugs (NSAIDs) and aspirin, in particular, on colorectal cancer is well established. More recently, it has been suggested that aspirin may also have a therapeutic role. Aim of the present observational population-based study was to assess the therapeutic effect on overall survival of aspirin/NSAIDs as adjuvant treatment used after the diagnosis of colorectal cancer patients.
  
  
  METHODS
  Data concerning prescriptions were obtained from PHARMO record linkage systems and all patients diagnosed with colorectal cancer (1998-2007) were selected from the Eindhoven Cancer Registry (population-based cancer registry). Aspirin/NSAID use was classified as none, prediagnosis and postdiagnosis and only postdiagnosis. Patients were defined as non-user of aspirin/NSAIDs from the date of diagnosis of the colorectal cancer to the date of first use of aspirin or NSAIDs and user from first use to the end of follow-up. Poisson regression was performed with user status as time-varying exposure.
  
  
  RESULTS
  In total, 1176 (26%) patients were non-users, 2086 (47%) were prediagnosis and postdiagnosis users and 1219 (27%) were only postdiagnosis users (total n=4481). Compared with non-users, a survival gain was observed for aspirin users; the adjusted rate ratio (RR) was 0.77 (95% confidence interval (CI) 0.63-0.95; P=0.015). Stratified for colon and rectal, the survival gain was only present in colon cancer (adjusted RR 0.65 (95%CI 0.50-0.84; P=0.001)). For frequent users survival gain was larger (adjusted RR 0.61 (95%CI 0.46-0.81; P=0.001). In rectal cancer, aspirin use was not associated with survival (adjusted RR 1.10 (95%CI 0.79-1.54; P=0.6). The NSAIDs use was associated with decreased survival (adjusted RR 1.93 (95%CI 1.70-2.20; P<0.001).
  
  
  CONCLUSIONS
  Aspirin use initiated or continued after diagnosis of colon cancer is associated with a lower risk of overall mortality. These findings strongly support initiation of a placebo-controlled trial that investigates the role of aspirin as adjuvant treatment in colon cancer patients.
authors.affiliation: Department of Surgery, Leiden University Medical Centre, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Bastiaannet
authors.forename: K
authors.initials: K
authors.lastname: Sampieri
authors.forename: O M
authors.initials: OM
authors.lastname: Dekkers
authors.forename: A J M
authors.initials: AJ
authors.lastname: de Craen
authors.forename: M P P
authors.initials: MP
authors.lastname: van Herk-Sukel
authors.forename: V
authors.initials: V
authors.lastname: Lemmens
authors.forename: C B M
authors.initials: CB
authors.lastname: van den Broek
authors.forename: J W
authors.initials: JW
authors.lastname: Coebergh
authors.forename: R M C
authors.initials: RM
authors.lastname: Herings
authors.forename: C J H
authors.initials: CJ
authors.lastname: van de Velde
authors.forename: R
authors.initials: R
authors.lastname: Fodde
authors.forename: G J
authors.initials: GJ
authors.lastname: Liefers
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use*; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009426:Netherlands / Q000453:epidemiology; D011379:Prognosis; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control*; D012307:Risk Factors; D015996:Survival Rate; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D001241:Aspirin