Bladder cancer

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Side effects of radiation therapy for bladder cancer

Side effects can happen with any type of treatment for bladder cancer, but everyone’s experience is different. Some people have many side effects. Other people have few or none at all.

During radiation therapy, the healthcare team protects healthy cells in the treatment area as much as possible. Damage to these healthy cells may cause side effects. Side effects can happen any time during, immediately after or a few days or weeks after radiation therapy. Sometimes late side effects develop months or years after radiation therapy. Most side effects go away on their own or can be treated, but some side effects may last a long time or become permanent.

Side effects of radiation therapy will depend mainly on the:

  • size of the area being treated
  • specific area or organs being treated
  • total dose
  • treatment schedule

Tell your healthcare team if you have these side effects or others you think might be from radiation therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.


Fatigue is one of the most common side effects of radiation therapy. Fatigue may be caused by anemia, poor appetite or depression. It may also be related to toxic substances that are made when cancer cells break down and die. During radiation therapy, the body uses more energy to heal itself, so fatigue will not always be relieved by rest. Making daily trips for radiation treatments can also be tiring.

Radiation therapy to any area of the body can make you feel more tired than usual, but fatigue is more common when larger areas of the body are treated. Anemia is more likely to occur when the treatment area includes bones where blood cells are formed in the bone marrow, such as the pelvic bones.

Fatigue usually occurs during or after the second week of radiation therapy. You may have more symptoms of fatigue or they may become more severe over the course of treatment. Fatigue usually goes away gradually after treatment has ended, but some people continue to feel tired for several weeks or months after radiation therapy.

Find out more about fatigue and anemia.

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Skin reactions

Skin reactions occur because external beam radiation travels through the skin to reach the area being targeted for treatment. The skin in the treated area may become red, dry or itchy. Most skin reactions occur within 2 weeks of receiving radiation treatment. They usually go away a few weeks after treatment. Some skin changes, like darkening or scarring, can last a long time.

Find out more about skin problems.

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Bladder problems

Radiation therapy can irritate the bladder and make it inflamed (called radiation cystitis). Symptoms of bladder irritation or inflammation include:

  • burning or pain during urination
  • intense need to urinate (called urinary urgency)
  • need to urinate often (called urinary frequency)
  • blood in the urine (called hematuria)
  • loss of bladder control (called urinary incontinence)

Symptoms usually occur 3–5 weeks after radiation therapy starts and go away after treatment is finished. Some symptoms may continue or develop after treatment is over.

Try to drink plenty of fluids to ensure a regular flow of urine and empty the bladder often. Report burning, pain and frequent urination to the radiation therapy team. These can also be symptoms of infection.

Medicines may be used to help treat some of the symptoms of bladder problems.

Find out more about urinary incontinence.

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Bowel problems

Radiation to the pelvis can irritate the intestines and cause a variety of bowel problems, including:

  • diarrhea
  • irritation and inflammation of the large or small intestines (called radiation enteritis)
  • pain or itching when having a bowel movement (if the rectal area is treated with radiation)
  • narrowing, or stricture, of the rectum
  • sudden, involuntary and often painful contraction of the rectal muscle (called rectal spasm)
  • some loss of bowel control (called partial incontinence)
  • irritation and inflammation of the rectum or anus (called proctitis), which causes bloody stools and a frequent urge to have a bowel movement
  • rectal bleeding
  • flare-up of hemorrhoids (especially if you had them before treatment)

Bowel habits usually return to normal and symptoms gradually go away after treatment is finished. Some symptoms may continue or develop after treatment is over.

The radiation therapy team can suggest ways to help manage diarrhea, itching and hemorrhoids. Treatment options for severe rectal problems may include:

  • anti-inflammatory drugs, corticosteroid drugs or medicines to treat spasms
  • dilation (widening) of rectal strictures
  • surgery (if bowel problems are severe)

Find out more about diarrhea and radiation enteritis.

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Hair loss

Hair loss, or alopecia, can occur in the area where radiation is directed. How much hair you lose and when and how it regrows is different for everyone. It depends on the dose of radiation.

Loss of some pubic hair may occur during radiation therapy to the pelvis. When treatment is finished, the hair often grows back. However, the hair may be thinner and finer than it was before treatment.

Find out more about hair loss.

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Fertility and sexual problems

Radiation therapy to the pelvis can affect the reproductive organs in men and women. Changes to reproductive organs can lead to:

  • fertility problems in both men and women
  • treatment-induced menopause, including vaginal dryness, in women
  • vaginal narrowing in women
  • erectile dysfunction, or impotence, in men

These can be long-term problems.

Find out more about fertility problems.

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Any steroid hormone that acts as an anti-inflammatory by reducing swelling and lowering the body’s immune response (the immune system’s reaction to the presence of foreign substances).

Corticosteroids are made by the adrenal gland. They can also be produced in the lab.


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