What are the symptoms of rectal cancer?

Changes may include constipation, looser stools, narrower stools, urgency, or switching between constipation and diarrhoea. A person may feel they still need to open the bowel after going. Blood can appear bright red on paper or mixed with stool; darker stool can suggest bleeding higher in the digestive tract.

Some people develop tiredness from ongoing blood loss, reduced appetite, abdominal bloating, or unintentional weight loss. Haemorrhoids, infections, inflammatory bowel disease, and other conditions can also cause these symptoms, so they need assessment rather than a self-diagnosis.

Contact a clinician when blood in stool, altered bowel habits, urgency, or incomplete emptying persists or keeps returning. Note the colour of blood, stool pattern, pain, mucus, and any family history of bowel disease. The assessment may involve an examination, blood tests, stool tests, and an endoscopic examination such as colonoscopy.

If rectal cancer is found, treatment is planned around its position, depth, and spread. It may include radiotherapy, chemotherapy before surgery, rectal resection, or stoma surgery. Your team can explain why a particular sequence is recommended.

Seek urgent care for heavy or continuous rectal bleeding, black tar-like stool, dizziness, fainting, severe abdominal swelling or pain, repeated vomiting, or inability to pass stool and gas. These signs can indicate significant bleeding or bowel blockage.

Ask what could explain the bowel change, whether you need an urgent referral, and which tests will clarify the cause. If cancer is diagnosed, ask how tumour location affects radiotherapy, surgery, bowel function, and the possible need for a stoma.