According to a study published more than 10 years ago, many women over 70 who are treated for early-stage breast cancer receive no additional benefit from radiation treatments, but a new study finds that nearly two-thirds of them continue to receive radiation treatment.
For some of those women, radiation may be appropriate, according to the authors of the new study, published in the journal Cancer. But for others, especially those who face additional health risks, radiation does not appear to reduce the recurrence of cancer or increase survival.
"We know that having a lumpectomy plus radiation reduces recurrence by 70 percent," said lead author Dr. Rachel C. Blitzblau, assistant professor of radiation oncology at Duke Cancer Institute in Durham, N.C. "It has a very big impact, so if you have a lumpectomy you should have radiation. Also, there are women over 70 who face a much higher risk of breast cancer, and we would never think of leaving radiation out for them."
Blitzblau suspects that many doctors continue to administer radiation for older breast cancer patients because studies that show it confers no significant benefit generally follow women for only five years. Maybe after 10 or 15 years those who received radiation would show lower rates of recurrence and longer survival.
That's a reasonable concern, Blitzblau said, and in fact she recommends radiation for older breast cancer patients who are extremely healthy and stand a chance of living another 20 or 25 years.
"It's not uncommon now for women to live into their 90s," she said. "For those women, early-stage breast cancer may still be the most threatening medical problem they face, so it may still be reasonable to consider radiation. Such women might get a huge reduction in their risk of recurrence."
However, older women who have diabetes, heart disease, dementia or other medical problems likely to shorten their lives would receive little, if any, benefit from radiation. Besides, older patients are more likely to develop "indolent" breast cancer, which is less aggressive and poses a smaller threat.
Above all, doctors should consider the wishes of each patient, Blitzblau said. "I can report the results of trials to two women and they'll respond very differently," she said. "One might say, 'I hear you saying there's a small benefit to the radiation and it won't improve survival, so I don't want to do it,' while the other woman says, 'I'd like my recurrence risk to be 2 percent rather than 9 percent in 10 years.' "
So given this new information, what should women do?
"I think the most important thing for patients is to ask their doctor what kind of benefit they can expect from treatment, and what side effects to expect," Blitzblau said. "In cancer treatment, we're always trying to decide if treatment will help the patient or be outweighed by side effects. If patients ask questions, they can weigh the pros and cons for themselves."
Tom Valeo writes on health matters. Contact him at email@example.com.