PT  - JOURNAL ARTICLE
AU  - Roma Robertson
AU  - Christine Campbell
AU  - David P Weller
AU  - Rob Elton
AU  - David Mant
AU  - John Primrose
AU  - Karen Nugent
AU  - Una Macleod
AU  - Rita Sharma
TI  - Predicting colorectal cancer risk in patients with rectal bleeding
DP  - 2006 Oct 01
TA  - British Journal of General Practice
PG  - 763--767
VI  - 56
IP  - 531
4099  - http://bjgp.org/content/56/531/763.short
4100  - http://bjgp.org/content/56/531/763.full
SO  - Br J Gen Pract2006 Oct 01; 56
AB  - Background Rectal bleeding is an important symptom of colorectal cancer but has low predictive value in primary care.Aim To determine which characteristics of rectal bleeding, along with other factors, are predictive of colorectal cancer.Design of study Observation study of patients with rectal bleeding referred to an open-access diagnostic clinic.Setting Primary care, southern England.Method Symptom data were collected, using a self-completed questionnaire. Logistic regression techniques were used to determine predictors of colorectal cancer.Results There were 604 patients in the study and 22 (3.6%, 95% confidence interval [CI] = 2.0% to 5.2%) were diagnosed with colorectal cancer. Significant predictors of colorectal cancer were found to be age (<50 years: odds ratio [OR] = 1; 50–69 years: OR = 5.1, 95% CI = 1.4 to 18.6; ≥70 years: OR = 8.2, 95% CI = 2.1 to 31.8) and blood mixed with the stool (Likelihood ratio [LR] 1.5; adjusted OR = 3.8; 95% CI = 1.4 to 10.5). Presence of haemorrhoids associated with bright red bleeding not mixed with stool reduced the likelihood of cancer (OR = 0.4, 95% CI = 0.1 to 1.2) but did not eliminate it — a cancer was present in 2% of patients with these symptoms.Conclusion Patient-reported type of rectal bleeding as an isolated symptom has insufficient diagnostic value to be useful in general practice. By studying referred patients, we may even have overestimated its value. At best, it could be useful as a component of a composite symptom score to guide referral decisions.