May 17, 2007 - According to a study recently today in the International Journal of Radiation Oncology Biology Physics, the official journal of ASTRO, elderly women who receive radiation therapy for early-stage breast cancer appear to have no increased risk of a heart attack after taking pre-existing cardiac risk factors into account. Pre-existing cardiac risk factors such as diabetes, hypertension and hyperlipidemia do not potentiate the effects of radiation on the heart.
Using the Surveillance, Epidemiology and End-Results (SEER) database, researchers conducted a retrospective study of female Medicare recipients aged 65 and older who were diagnosed with breast cancer from 1992 to 2000. Researchers then reviewed the records of more than 48,000 breast cancer patients. Of those women, 19,897 had lumpectomies (42 percent) and 26,534 had mastectomies (55 percent). Of all the patients in the study, 21,502 (45 percent) received radiation therapy and 4,151 (9 percent) received both radiation and chemotherapy. Patients with pre-existing heart disease were less likely to receive radiation.
After adjusting for pre-existing heart problems as well as other health and socioeconomic factors like age, race, marital status, income, rural versus urban living and receipt of chemotherapy, doctors found that women who received radiation were not at an increased risk of having heart attacks. As would be expected, heart attacks were more likely to be found among individuals already at higher risk for heart disease, such as women of increased age, African-American ethnicity and those with more co-morbid conditions.
February 16, 2026 
