Radiation therapy uses high-energy radiation to kill cancer cells. External beam radiation therapy focuses radiation from outside of the body on the cancer. Local or interstitial radiation therapy uses a small pellet of radioactive material placed directly into the cancer.
 

After surgery, radiation can kill small deposits of cancer cells that may not be visible during surgery. The combination of radiation therapy and chemotherapy given after transurethral bladder surgery is sometimes able to completely destroy cancers that would otherwise need to be treated with cystectomy. This approach can be used to treat smaller tumors (about an inch or less in size) as long as there are no signs of kidney blockage. If the treatment doesn't work or the cancer comes back, you will need cystectomy.
 

Side effects of radiation depend on the dose given and the area being treated and they tend to be worse if chemotherapy is given with the radiation. Side effects may include:

• skin changes - ranging from redness to severe irritation with blistering
• nausea and vomiting
• bladder symptoms, like burning or pain with urination, feeling the need to go often, or blood in the urine
• diarrhea
• fatigue
• low blood counts

These symptoms are usually temporary, although long-term problems sometimes occur. In some people radiation treatments can lead to incontinence (problems holding urine) later on. In some, radiation can damage the lining of the bladder. This is known as radiation cystitis and can cause long-term problems such as blood in the urine or pain with urination. If you have side effects from radiation therapy, you should discuss them with your health care team. They can suggest ways to ease many of these discomforts.