Updated

Some elderly women with early-stage breast cancer may be getting extra treatment that does them little good but comes with costs and possible side effects, according to a new study.

Researchers found that about three-quarters of women 70 and older with stage I breast cancer were treated with radiation to stave off recurrences, in addition to standard breast-conserving surgery.

Current guidelines say it's generally okay to skip radiation in those patients, as it hasn't been shown to help them live longer.

One of the main issues with radiation is not that it has a really high complication rate. The question is, are the benefits really there?" said Dr. Cary Gross, from the Yale School of Medicine in New Haven, who worked on the study.

Some women have skin irritation or discomfort after radiation, while lung, bone or heart problems near the site of the radiation are much more rare, Gross said.

In addition, there's the inconvenience of getting to appointments -- which may be more of a burden in the elderly. Radiation therapy costs about $7,000, paid for in older people by Medicare.

In one 2004 study, researchers including Dr. Kevin Hughes from the Harvard Medical School in Boston found that adding radiation on top of breast-conserving surgery didn't improve survival in elderly stage I breast cancer patients, probably because of differences in tumor characteristics in older women.

That prompted the no-radiation option to be added to guidelines from the National Comprehensive Cancer Network in 2005, meaning optimal treatment of that group could include or not include radiation.

To see whether those changes affected care, Gross and his team analyzed data from close to 13,000 women, age 70 and older, who were covered by Medicare and diagnosed with stage I breast cancer between 2001 and 2007.

Of those women, almost 77 percent were treated with radiation along with breast-conserving surgery, with only a slight decline before and after the 2004 report and subsequent guidelines change.

Among women expected to live less than five years based on their age and other diseases, 44 percent received radiation before the report, and 41 percent after, according to findings published in the Journal of Clinical Oncology.

More treatment, similar outcome

In the 2004 study, one percent of women who had breast-conserving surgery and radiation had a cancer recurrence by five years, compared to four percent of those who only received surgery, also known as lumpectomy.

Those women were all also prescribed the breast cancer drug tamoxifen.

That means you have to basically treat 33 women (with radiation) in order to prevent one recurrence at five years," Gross told Reuters Health, noting that recurrences are treatable.

The problem is this: you don't know which of the 33 women is the one you're going to help."

When Hughes' team tracked the same women from the original report out ten years, the researchers still didn't find a difference in deaths between the two treatment groups.

Still, even after the guideline change, Gross said, doctors may chose to treat older women with radiation to feel like they're doing everything they can for their patients.

Hughes told Reuters Health that it's “disappointing" more doctors haven't followed the evidence and stopped using radiation so far, but he expects that shift will come slowly.

As physicians we don't want to give any treatment to a patient that's not necessary," added Hughes, who didn't participate in the current study.

The researchers agreed that older women would gain from being more involved in decisions about their own cancer care.

We need to do a better job of allowing patients to make informed choices," Gross said.

Hughes said that older patients should also speak up and ask their doctors whether they really need radiation.

It's time to start decreasing the amount of treatment we're giving, if we're getting the same effect in the long run," he said.