Radiation
Radiation treatment is commonly used to treat a variety of cancers, including prostate cancer. Radiation therapy works by bombarding cancerous tumors with high energy X-ray beams. These beams cause damage to cells that are rapidly dividing, killing them. Because cancer cells tend to divide more rapidly than the tissue around them, radiation therapy tends to damage the cancer cells more than the healthy surrounding tissue. In the case of prostate cancer, radiation is typically delivered from outside the body by a machine that generates the X-ray beams, a process called external beam therapy.
Procedure
The first step for treating prostate cancer with radiation therapy is called the simulation. During the simulation, the "target area" is marked on the skin using red ink. A computed axial tomography, or CAT, scan machine is then aimed at the target area using a laser beam that helps make sure the machine is oriented properly. Next, the CAT scan takes an image of the area, which generates a three-dimensional image of the tumor. This allows the radiologists to use a computer to determine the best angles and plan for delivering the radiation, since the beams can be aimed at the tumor from a variety of angles. This plan allows the radiologists to efficiently deliver the most radiation to the tumor without causing too much damage to the surrounding tissue. The treatment is given five days a week for seven or eight weeks, with each session lasting 20 to 30 minutes.
Side Effects
Although radiation therapy is designed to minimize the damage to the surrounding tissue, some damage does occur. Side effects from the treatment typically begin during the fourth week of treatment and can last for up to two years. These side effects include irritation of the skin near the prostate and of the anus. Diarrhea, cramping, and abdominal discomfort may also occur, although these can be treated with anti-diarrhea and gas medications. Radiation can also cause patients to urinate more frequently and experience a burning sensation when urinating. Patients may also experience loss of their pubic hair and mild scarring around the prostate.
