Dear Dr. SerVaas,

I have a question about radiation implants for prostate cancer. Can these radiation implants destroy the muscles and nerves in the rectum and colon? Your reply to this question will be sincerely appreciated.

Milton Lesemann
Edwardsville, Illinois

We sent your letter to Dr. Michael Koch, IU chair of the department of urology, Dr, Koch explains:

"Sufficient amounts of radiation can destroy any tissue. When prostate cancer is treated with radiation therapy, techniques are always employed to minimize the dose to the rectum. In most cases, the impact on nerves and muscles in the radiation field is minimal."