Pelvic radiotherapy can damage the nerves that control the bladder muscles. It can also narrow the tube that carries urine out of the body (the urethra).

About difficulty passing urine

Sometimes after pelvic radiotherapy you may have difficulty passing urine. This is called retention. It can happen if the nerves that control the bladder are damaged or if the tube that drains urine from the body (the urethra) is narrowed, called a urethral stricture.

These may start during treatment and not get better. Or it may develop months or years after treatment.

If you have any difficulty passing urine, it is important to get this checked. If urine builds up in the bladder, it can cause infections and damage the kidneys. Your doctor or continence adviser will do tests to find out the cause so they can offer you the right treatment for your situation.

Nerve damage

Sometimes, nerve damage means the bladder muscle cannot squeeze strongly enough. This means the bladder does not empty completely.

Some people may need to use a catheter to empty their bladder a few times a day. This is called intermittent self-catheterisation. Your doctor or continence adviser can tell you more about this.

Urethral stricture

Narrowing of the urethra (a urethral stricture) can be treated in several ways, depending on its size.

Small strictures can be treated by passing a thin, plastic tube through the urethra to widen (dilate) it. This can be done under a general or local anaesthetic. Sometimes it may need to be repeated.

Another possible treatment for smaller strictures is an operation called a urethrotomy. This is done under a spinal anaesthetic (where you are awake but do not feel anything from the waist down) or general anaesthetic. The surgeon passes a cystoscope (a thin tube with a camera on the end) into the urethra. This lets them make small cuts to widen the urethra.

A larger stricture may need to be treated with an operation that uses tissue from another part of the body to repair the urethra. This is called a reconstruction.

If bladder problems do not improve

If your bladder symptoms continue or do not improve after having these treatments, your specialist may talk to you about other possibilities. When symptoms are severe, an operation to remove the bladder may be an option, but this is rare.

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