Women with early-stage breast cancer who need to undergo lumpectomy must choose one of three types of radiation. If you’re ever faced with this difficult decision, weigh your options carefully, because a new study shows that depending on the type of radiation you choose, the odds of the cancer returning and your having to get a mastectomy can be very different.
One kind, called intraoperative radiation therapy, can be performed during the lumpectomy, but it has yet to gain widespread implementation in the US (there is some data supporting its use, but it’s considered controversial). A more traditional approach is whole-breast radiation, which radiates the entire breast after the lumpectomy. The third technique is brachytherapy. Also performed after the lumpectomy, this partial breast radiation delivers a targeted dose of radiation only to and around the tumor(s) through an implanted catheter. Brachytherapy is often an option, though not always, because the tumor has to have a certain geometry to allow for safe placement of the catheter.
To discuss the pros and cons of each type of breast cancer radiation, I called the study’s lead author, Benjamin Smith, MD, assistant professor of radiation oncology at The University of Texas MD Anderson Cancer Center in Houston—and he told me that even he was surprised by what his study discovered.
TWO TYPES OF TREATMENT
Before we jumped into the research, Dr. Smith told me more about the two main kinds of radiation—whole breast and brachytherapy—and why a woman might choose one over the other. Approved by the FDA in 2002, brachytherapy definitely has its advantages. While whole-breast radiation typically requires daily hospital visits for three to seven weeks, brachytherapy can be done twice a day over about one week—a big benefit for many women, including those with work or child-care schedules that are hard to alter and older women who are perhaps less mobile than their younger counterparts, Dr. Smith said. This added convenience surely factors into the therapy’s increasing popularity.
WHICH IS MORE EFFECTIVE?
Dr. Smith told me that his research, which he presented in December 2011 at the San Antonio Breast Cancer Symposium, was the first to amass data comparing whole-breast radiation with brachytherapy from across the US and that it included more women who underwent brachytherapy than any prior study. He and his colleagues looked at the Medicare records of 130,535 women who were all over the age of 66, had been diagnosed with early-stage breast cancer, and had undergone a lumpectomy and then either brachytherapy or whole-breast radiation. (Intraoperative radiation therapy was not part of this study.)
The vast majority of women in the study chose to undergo whole-breast radiation—only about 7,300 of them (or about 6% of them) chose brachytherapy. But of those 7,300 women, the researchers found that 4% of them had mastectomies in the following five years…compared with only 2.2% of the women who chose whole-breast radiation. While the mastectomy percentages in both groups were small, the difference does represent nearly double the risk of having to have a mastectomy within five years of having brachytherapy. When Dr. Smith and his team plucked out only the women who had mastectomies because their cancer had returned (not due to side effects like, say, a radiation burn), they still had double the risk.
So why doesn’t brachytherapy appear to be as effective? Since it treats only the tumor and about a centimeter around it, rogue cancer cells lurking in another part of the breast—while uncommon—may be missed, Dr. Smith said.
In terms of complication rates, brachytherapy also didn’t fare well. Nearly 16% of women treated with brachytherapy experienced a complication after their procedure, compared with 8% in the whole-breast radiation group. And the infection rates were 16%, versus 10%, respectively. But the complication and infection rates didn’t surprise Dr. Smith. “When you have a catheter implanted in your breast, there is a real risk that bacteria will enter the body, especially if patients, physicians and the nursing staff do not pay meticulous attention to keeping the catheter clean,” said Dr. Smith.
IT’S YOUR DECISION
This study certainly suggests that whole-breast radiation has several advantages compared with brachytherapy. But, since life is far from simple, other factors may make brachytherapy the best choice for some women—even those who learn about these new statistics, said Dr. Smith. “Some patients might feel that a 4% return rate of cancer is still quite low, and they might be delighted to choose brachytherapy and do one week of radiation rather than suffering through three to seven weeks of it,” he said. “But other patients may want to do everything in their power to give themselves the highest chance for a cure—or the idea of having a catheter implanted in their chest, which is more invasive, might really concern them, so those women might opt for whole-breast radiation.”
Brachytherapy is only 10 years old, said Dr. Smith, so large, long-term studies haven’t been performed until now. As more data emerges, doctors will have an even clearer picture of the benefits and risks—and you know I’ll keep you posted.