Radiation treatment for breast cancer can increase a woman’s
risk of heart disease, doctors have long known. But the size of
the added risk has not been clear. Now, a new study offers a way
to estimate the risk. It finds that for most women the risk is
modest, and that it is outweighed by the benefit from the
treatment, which can halve the recurrence rate and lower the
death rate from breast cancer by about one-sixth. According to
the study, a 50-year-old woman with no cardiovascular risk
factors has a 1.9 percent chance of dying of heart disease
before she turns 80. Radiation treatment for breast cancer would
increase that risk by 2.4 percent to 3.4 percent, depending on
how much radiation hits the heart. “It would be a real tragedy
if this put women off having radiotherapy for breast cancer,"
said Sarah Darby, a professor of medical statistics at the
University of Oxford in Britain, and the lead author of the
study, published earlier this week in The New England Journal of
Medicine. Dr. Silvia Formenti, the