WEDNESDAY, Jan. 19, 2005 (HealthDayNews) -- Adding radiation therapy to chemotherapy improves survival in patients with high-risk breast cancer who have had a modified radical or full mastectomy, a 20-year follow-up on a key study finds.
The new report includes two decades of followup on patients who began treatment from 1979 through 1986. "We have confirmed with even more significance that, as time goes on, the survival difference is even more significant," said Dr. Joseph Ragaz, director of oncology at the McGill University Health Center in Monteal and the lead author of the new research.
In the original trial, known as the British Columbia randomized radiation trial, 318 breast cancer patients were randomly assigned to either receive radiation therapy after a modified radical mastectomy and chemotherapy or get no additional therapy.
In an earlier follow-up, encompassing 15 years, radiation therapy was associated with a significant improvement in breast cancer survival but a borderline statically significant improvement in overall survival.
The 20-year follow-up found improvement in all aspects: the addition of radiation therapy resulted in a 32 percent reduction in breast cancer deaths and a 27 percent reduction in overall deaths compared to the use of just chemotherapy after surgery.
The findings appear in the Jan. 19 issue of the Journal of the National Cancer Institute.
All the patients in the study had high-risk breast cancer, defined as having at least four lymph nodes involved, Ragaz said.
And while the study did not cover the value of radiation therapy for lumpectomy patients, Ragaz added, "Our data is acceptable enough to say, whether the breast is left or not, [if] the patient is high risk . . . . radiation should be given to the lymph nodes and the breast to improve survival."
"The study is really good news," said Dr. Timothy Whelan, an associate professor of medicine at McMaster University in Hamilton, Ontario, who wrote an editorial accompanying the report. "It confirms findings from years ago. This study shows if radiation is given carefully and to the right group of patients, it can be a win-win situation."
In previous research, radiation has been associated with an increase in some instances of heart disease, but those studies involved radiation given to the heart area, Whelan said.
"Now, with newer techniques, we can avoid radiation to the heart pretty much entirely," he said.
In the study period reported by Ragaz, the radiation involved targeting the heart area but the benefits persisted, he said.
What is yet to be studied, Whelan said, is whether women at moderate risk of recurrence should also get radiation therapy.
Ragaz is now studying whether radiation should also be used in patients with fewer lymph nodes involved.
To learn more about radiation therapy and its effects, visit the American Cancer Society.