Intra-abdominal cancer risk with abdominal pain: a prospective cohort primary-care study

Abstract

Background: Quantifying cancer risk in primary-care patients reporting abdominal pain would inform diagnostic strategies. Aim: To quantify oesophagogastric, colorectal, liver, pancreatic, ovarian, uterine, kidney and bladder cancer risks associated with newly reported abdominal pain with or without other symptoms, signs or abnormal blood tests (i.e. features) indicative of possible cancer. Design and setting: Observational prospective cohort study using Clinical Practice Research Datalink records with English cancer registry linkage. Methods: Participants (N=125,793) aged ≥40 years had newly reported abdominal pain in primary care during 01/01/2009-31/12/2013. The outcomes were 1-year cumulative incidence of cancer, and the composite 1-year cumulative incidence of cancers with shared additional features, stratified by age and sex. Results: With abdominal pain, overall risk was greater in men and increased with age, reaching 3.4% (95%CI 3.0–3.7%; predominantly colorectal cancer 1.9%, 1.6–2.1%) in men ≥70 years, compared with their expected incidence of 0.88% (0.87%–0.89%). Additional features increased cancer risk; for example, colorectal or pancreatic cancer risk with abdominal pain plus diarrhoea at 60–69 and ≥70, respectively, was 3.1% (1.9–4.9%) and 4.9% (3.7–6.4%), predominantly colorectal cancer (2.2%, 2–3.8% and 3.3%, 2.0–4.9%). Conclusions: Abdominal pain increases intra-abdominal cancer risk nearly fourfold in men aged ≥70, exceeding the 3% threshold warranting investigation. This threshold is surpassed for the over-60s only with additional features. These results help direct appropriate referral and testing strategies for patients based on their demographic profile and reporting features. We suggest non-invasive strategies first, such as faecal immunochemical testing, with safety-netting in a shared decision-making framework.