Radiotherapy for bladder cancer: what to know

External-beam radiotherapy directs radiation from a machine towards the bladder and the area selected by the oncology team. Planning scans help map the bladder, tumour and nearby bowel. Treatment may be combined with chemotherapy, used after an operation, or chosen as part of a bladder-preserving plan. The exact approach depends on tumour features, scans, previous treatment and your general health.

During a course, you usually attend repeated appointments. Side effects can build gradually. Bladder irritation may cause more frequent or urgent urination, burning, or difficulty passing urine. Bowel irritation can lead to looser stools or discomfort. Skin in the treated area may become sensitive. Your team can adjust supportive care as symptoms change.

Ask how to prepare your bladder before each session and whether your medicines need review. Keep a record of urinary and bowel changes, drink according to the instructions given to you, and protect treated skin from friction or unapproved creams. Attend planning and review appointments so the team can check your response and manage side effects. Cystoscopy or scans may be used to assess the bladder, while surgery, chemotherapy, immunotherapy or intravesical BCG may be discussed in different situations.

Contact your oncology team promptly if you cannot pass urine, develop increasing blood in the urine, have severe pain, repeated vomiting, worsening diarrhoea, fever, or feel suddenly unwell. Difficulty passing urine needs timely assessment because bladder irritation, swelling or another problem may need treatment. Seek emergency help for severe weakness, confusion, collapse, or breathing difficulty.

Which part of the bladder and nearby tissues will be treated? Is the aim to control the cancer, relieve a symptom, or support bladder preservation? How will treatment affect urination, bowel function and daily activities? What symptoms should be reported the same day?