How effective is radiotherapy for rectal cancer?

Radiotherapy targets the rectum and nearby tissues to damage cancer cells. Before surgery, it may reduce the tumour's extent and help the surgeon achieve local control. It can also be used after surgery in selected situations, or to ease bleeding, pain or pressure when the cancer cannot be removed immediately.

The benefit depends on the tumour's height in the rectum, depth through the bowel wall, lymph-node involvement, nearby organ relationships and whether chemotherapy is included. Response is assessed with examination, scans and sometimes endoscopy. Bowel habit changes, tiredness, skin irritation and urinary or sexual effects can occur, and the team can offer measures to manage them.

Ask whether radiotherapy is being used before surgery, after surgery, or for symptom relief. Confirm how the target will be defined, how bowel and bladder preparation works, how chemotherapy fits in, and when surgery or reassessment is expected. Tell the team about inflammatory bowel disease, prior pelvic treatment, bowel obstruction and current medicines.

Call the treatment team promptly for persistent vomiting, inability to keep fluids down, worsening abdominal swelling, severe diarrhoea, fever, increasing rectal bleeding or inability to pass stool or gas. Emergency help is needed for collapse, severe abdominal pain, heavy bleeding or confusion.

What is the purpose of radiotherapy in my sequence of care? Could it change the operation planned? Will chemotherapy be given with it? How will response be measured, and which bowel or urinary changes require urgent advice?