Shorter, More Intense Radiation OK for Some Breast Cancers
WEDNESDAY Nov. 4, 2009 -- A shorter, more intense course of whole-breast radiation works as well as the traditional six-week course, at least for some early-stage breast cancers, a new study shows.
"This concept of a shorter length of treatment is gaining acceptance," said Dr. Manjeet Chadha, associate chair of radiation oncology at Beth Israel Medical Center and associate professor of radiation oncology at Albert Einstein College of Medicine, both in New York City. Chadha led the study and is scheduled to present the results Wednesday at the American Society for Radiation Oncology annual meeting, in Chicago.
Researchers previously have tried to investigate whether they can alter the duration of radiation therapy or the volume, Chadha said. "My study focuses on the duration of it," she said.
In her three-week treatment -- called accelerated hypofractionated whole breast irradiation -- a woman gets the entire affected breast irradiated and receives a ''boost,'' or extra dose, at the site where the tumor was removed. Other approaches include giving a boost dose after the entire radiation treatment to the whole breast is completed.
Chadha's study is ongoing, but she planned to report on 122 patients with early-stage breast cancers who underwent lumpectomies followed by the accelerated treatment. They were then tracked for a median of two and a half years (half followed longer, half less). The patients' median age was 66.
No relapses were noted, and the three-year survival rate was nearly 95 percent, Chadha said.
''It sounds encouraging," she said of her results. To further evaluate the accelerated treatment, she compared the first 50 patients on the briefer approach to a matched group of 70 patients who got the more traditional six-week radiation treatment.
Side effects, such as skin irritation and redness, were similar, she found. ''There was no difference in fatigue or breast edema [swelling]," she said. The cosmetic results were satisfactory, too.
The new study adds some valuable information for doctors trying to decide for individual women which radiation treatment approach might be best, said Dr. Nayana Vora, a professor of radiation oncology and associate member of the developmental cancer therapeutics program at the City of Hope Comprehensive Cancer Center in Duarte, Calif.
''It's a short follow-up,'' she said, noting that some side effects may surface later. But, she noted that a study outside the United States that looked at the briefer treatments has followed patients for up to 12 years with results similar to Chadha's study.
''Very few studies have been documented in the U.S. with external whole beam [to the whole breast] and a concomitant boost," Vora said. ''It tell us that, yes, patients can be treated with a short course of radiation treatment. Will it become the standard of care? I don't know."
While Vora typically offers her patients the six-week treatment unless they can't commit to that time period because of transportation problem or other obstacles, she said she now may consider the shorter treatment.
In another study to be presented at the oncology meeting, researchers reported that breast cancer patients who have a mastectomy and then receive radiation to the lymph nodes behind the breast bone (the internal mammary lymph nodes) do not live longer than those who don't get those nodes treated.
The study evaluated 1,334 women with stage 1 or 2 breast cancers that had spread to the axillary lymph nodes under the arms or whose original tumor was in a central, internal location. All got radiation to the chest wall and nodes above the collar bone. But half got the internal mammary radiation and half did not.
After a decade, survival differences between the groups were small, with 60 percent of those who didn't get the extra radiation still alive, and 63 percent of those who got it surviving.
Most radiation oncologists are reluctant to radiate the internal mammary nodes, Vora explained, because of their proximity to the heart.
To learn more about radiation therapy, visit the U.S. National Library of Medicine.
Posted: November 2009