Reducing Radiation Risk

Reducing the Risks of Radiation Therapy
According to the American Society for Therapeutic Radiology and Oncology, about 50 to 60 percent of cancer patients receive radiation therapy. The treatment uses high doses of energy to destroy cancer cells or inhibit the ability of the cells to grow and divide. The treatment may be given before surgery to shrink a tumor or after surgery to control or prevent growth, or reduce the risk of recurrence. In a typical treatment regimen, patients receive radiation therapy five days a week for 5 to 7 weeks.

One of the risks associated with radiation therapy is the chance of developing a second cancer. Researchers first noticed an increase in cancer rates in survivors of the atomic bomb blast in Japan. Some cases of leukemia are believed to be related to earlier treatment with radiation therapy. In some cases, secondary cancers can occur more than 15 years later.

When patients receive radiation therapy for breast cancer, the beams of energy are aimed at the site of the tumor. However, some of the radiation can scatter over the other breast. Doctors say a single radiation treatment can expose the opposing breast to a radiation equivalent of 40 to 60 mammograms, or at least 30 dental X-rays. That extra radiation can increase the risk of developing another breast cancer. The risk is greatest for younger women under 45.

To reduce exposure from unintentional (scatter) radiation, doctors at Eastern Virginia Medical School have developed a moldable breast shield. The shield is made from thin sheets of lead. Since lead is a soft metal, it can be shaped to precisely cover the breast. Doctors say the device is easy to make and cheap – costing only about $2.00/shield.

The breast shield doesn't completely eliminate unwanted radiation exposure since some of the energy can scatter sideways inside the body. However, doctors estimate the shield reduces the dose of scatter radiation by about 300 percent. The shield is only recommended for patients 50 and under. In older women, scatter radiation appears to have little effect on the risk for breast cancer.

For information on radiation therapy: American Society for Therapeutic Radiology and Oncology (ASTRO), 12500 Fair Lakes Circle, Suite 375, Fairfax, VA 22033,

For information on breast cancer:
American Cancer Society, contact your local chapter, or visit their website at
National Cancer Institute,, or (800) 4-CANCER