title: Effect of low-dose aspirin use on survival of patients with gastrointestinal malignancies; an observational study.
abstract: Previous studies suggested a relationship between aspirin use and mortality reduction. The mechanism for the effect of aspirin on cancer outcomes remains unclear. The aim of this study was to evaluate aspirin use and survival in patients with gastrointestinal tract cancer.
  
  
  
  Patients with gastrointestinal tract cancer diagnosed between 1998 and 2011 were included. The population-based Eindhoven Cancer Registry was linked to drug-dispensing data from the PHARMO Database Network. The association between aspirin use after diagnosis and overall survival was analysed using Cox regression models.
  
  
  
  In total, 13 715 patients were diagnosed with gastrointestinal cancer. A total of 1008 patients were identified as aspirin users, and 8278 patients were identified as nonusers. The adjusted hazard ratio for aspirin users vs nonusers was 0.52 (95% CI 0.44-0.63). A significant association between aspirin use and survival was observed for patients with oesophageal, hepatobiliary and colorectal cancer.
  
  
  
  Post-diagnosis use of aspirin in patients with gastrointestinal tract malignancies is associated with increased survival in cancers with different sites of origin and biology. This adds weight to the hypothesis that the anti-cancer effects of aspirin are not tumour-site specific and may be modulated through the tumour micro-environment.
authors.affiliation: Department of Surgical Oncology, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Frouws
authors.affiliation: Department of Surgical Oncology, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Bastiaannet
authors.affiliation: MRC Clinical Trials Unit, University College London, Institute of Clinical Trials and Methodology, Aviation House 125 Kingsway, London WC2B 6NH, UK.
authors.forename: R E
authors.initials: RE
authors.lastname: Langley
authors.affiliation: Department of Medical Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore.
authors.forename: W K
authors.initials: WK
authors.lastname: Chia
authors.affiliation: PHARMO Institute for Drug Outcomes Research, Van Deventerlaan 30/40, Utrecht 3528 AE, The Netherlands.
authors.forename: M P P
authors.initials: MP
authors.lastname: van Herk-Sukel
authors.affiliation: Comprehensive Cancer Organisation The Netherlands, Eindhoven 5600 AE, The Netherlands.|Department of Public Health, Erasmus MC Medical Centre, PO Box 2040, Rotterdam 3000 CA, The Netherlands.
authors.forename: V E P P
authors.initials: VE
authors.lastname: Lemmens
authors.affiliation: Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Putter
authors.affiliation: Department of Surgical Oncology, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: H H
authors.initials: HH
authors.lastname: Hartgrink
authors.affiliation: Department of Surgical Oncology, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: B A
authors.initials: BA
authors.lastname: Bonsing
authors.affiliation: Department of Surgical Oncology, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: C J H
authors.initials: CJ
authors.lastname: Van de Velde
authors.affiliation: Department of Medical Oncology, Haga Hospital, Leyweg 275, The Hague 2545 CH, The Netherlands.
authors.forename: J E A
authors.initials: JE
authors.lastname: Portielje
authors.affiliation: Department of Surgical Oncology, Leiden University Medical Center, Leiden 2300 RC, The Netherlands.
authors.forename: G J
authors.initials: GJ
authors.lastname: Liefers
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001241:Aspirin / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D001241:Aspirin