A woman with breast cancer who has had a lumpectomy also may have radiation to improve her odds of beating the disease. However, her heart and lungs wind up being exposed to the radiation, too, which increases her long-term risk of developing potentially deadly heart problems or lung cancer. New research suggests a simple way to reduce this risk—just have the woman roll over. Here’s the idea…

Usually, a woman receiving radiation lies on her back to give access to the breast tissue being targeted. Researchers wondered what would happen if she were instead to lie on her stomach, on a table that has an opening so that the affected breast is hanging down and not squished beneath her.

The study included 400 breast cancer patients. Half had had a lumpectomy in the right breast and the other half had had a lumpectomy in the left breast. Normally, prior to radiation, a CT scan is done to pinpoint the location of the breast tissue being targeted. For this study, each participant had two CT scans—one lying faceup and the other lying facedown—so that researchers could compare the amount of lung and heart tissue that would be within the radiation field in each position. (The amount of radiation from the extra CT scan was nowhere near as potentially harmful as the radiation used in actual cancer treatments.)

Results: In all patients, the facedown position vastly reduced the lung volume that was exposed to radiation, as compared with the faceup position. For women with left breast cancer, it was a whopping 91% reduction…for women with right breast cancer, it was an 86% reduction.

To gauge the effects on the heart, researchers looked only at the women who had had cancer in the left breast (since the heart risk is much smaller when the right breast receives radiation). Among these patients, the facedown position reduced the amount of heart tissue within the field of radiation by 86%, on average, as compared with the faceup position. However, for 15% of these women—most of whom had relatively small breasts—the faceup position was either the same or slightly better for reducing heart exposure.

Keep in mind that this is a preliminary study. The researchers did not actually compare the long-term effects of faceup versus facedown radiation treatment, so there’s no way yet to quantify how a patient’s position would affect her odds of developing heart or lung problems from radiation. Still, the data in radiation oncology suggest that keeping normal tissue out of the radiation field drastically reduces the risk for treatment complications.

More studies will come. In the meantime, if you or a woman you love ever needs radiation for breast cancer, talk to your oncologist about the possible advantages of the facedown position. Some radiation centers already provide facedown breast radiation, with the dose coming from below or from the side rather than from above—so ask your doctor for a referral. Why take chances with your heart or lungs if you might be able to avoid it just by rolling over?