Radiation therapy for early stage breast cancer carries a small, but real, risk of heart disease, new research finds.
The lifetime risk ranges from 0.05 percent to 3.5 percent, depending on how the radiation was delivered and a woman’s overall risk for heart disease, the researchers report.
Women at greatest risk are the ones receiving radiation on their left breast while lying on their back and who also are at risk for heart disease.
Radiation of the left breast ups the risk since that also exposes the heart to radiation, the study authors explained.
The lowest risk is among women receiving radiation for their right breast while lying face down. When radiation is given on the right side, the heart is totally out of the field of radiation, they noted.
“Our findings confirm that the radiation exposure associated with left-breast cancer radiotherapy is associated with a generally small, increased risk of heart disease later in life,” said lead researcher David Brenner, a professor of radiation biophysics at Columbia University Medical Center, in New York City.
“Of course, that side effect needs to be balanced against the fact that lumpectomy plus radiation is of well-proven efficacy for treating early stage breast cancer,” he said. “All cancer therapies involve balancing benefits and risks.”
In addition, the doses of radiation used today are much lower than they were 20 years ago, so the heart receives less exposure than it once did. “The risk of radiation-associated heart disease is lower for patients treated now than it was in the past,” Brenner added.
For women who need radiation for their left breast, the risk of developing heart disease can be lessened by lying face down during treatment, the researchers found.
In addition, since women most at risk of developing heart disease are those who are already at risk for it, Brenner suggests they can reduce their risk by not smoking and keeping blood pressure and cholesterol under control.
The report was published in a research letter online Oct. 28 in the journal JAMA Internal Medicine.
Read more at: MedlinePlus