This Week In The Bmj

Rectal bleeding indicates colorectal cancer more accurately after age 60

BMJ 2000; 321 doi: (Published 21 October 2000) Cite this as: BMJ 2000;321:g

To study the value of rectal bleeding presenting in general practice in diagnosing colorectal cancer Wauters et al used data from a network of general practitioners to perform a prospective study of patients presenting with rectal bleeding in 1993–4 and a retrospective study of those diagnosed with colorectal cancer in the same period (p 998). Among 83 890 patient years, 106 patients had colorectal cancer, and of these 31 had consulted their doctor with rectal bleeding (sensitivity 29.2%). Among 386 patients with bleeding 27 had cancer (positive predictive value 7.0%). Positive predictive value, but not sensitivity, increased with age. The authors conclude that the probability of cancer in people with rectal bleeding increases greatly in those over 60 and in association with fatigue, weight loss, and a palpable mass.