How common is blood in stool in rectal cancer?

Rectal cancer can bleed when a growth in the rectum is irritated by passing stool. Blood may be visible as bright red blood, or it may be mixed with stool. Bleeding can come and go, so an episode that settles does not establish what caused it. Haemorrhoids, anal fissures, bowel inflammation, and other problems can also lead to blood in stool.

Book a medical appointment for any new, unexplained, or recurring blood in stool. A clinician may ask about the timing and appearance of bleeding, changes in stool shape or bowel habit, abdominal symptoms, and medicines. They can decide whether an examination, blood tests, or inspection of the bowel is appropriate. Bring a list of symptoms and relevant family history.

Get urgent help for heavy bleeding, dizziness, fainting, severe belly pain, black tar-like stool, or severe weakness. Seek prompt review when bleeding accompanies an ongoing change in bowel habit, unexplained weight loss, increasing tiredness, or a sensation that the bowel does not empty. Urgency depends on these warning signs, not on guessing the cause.

Ask what examinations could identify the bleeding source, what other symptoms matter in your case, and how soon you should return if bleeding recurs. Tell the clinician about blood-thinning medicines, prior bowel tests, inflammatory bowel disease, and bowel cancer in close relatives.