Shorter, more intense courses of radiation treatment work just as well as more drawn-out therapy for early-stage breast cancer patients, researchers reported.
The treatments took only one to three weeks, as opposed to five to seven weeks for standard therapy, two teams of researchers told a meeting of the American Society for Therapeutic Radiology and Oncology in Boston on Monday.
Canadian researchers tested the approach, called accelerated hypofractionated whole breast irradiation, in 1,200 women randomly assigned to either accelerated radiation treatment or standard therapy between 1993 and 1996.
The alternative approach requires three weeks of daily, 15-minute visits compared to five weeks of standard therapy and cost two-thirds as much.
After 10 to 12 years, cancer had returned in 6.2 percent of patients treated with accelerated radiation therapy, compared to 6.7 percent of patients given standard therapy.
"We were surprised that the risk of local recurrence and side effects for women treated with accelerated whole breast irradiation was so low even at 12 years," said Dr. Timothy Whelan of McMaster University in Hamilton, Ontario, who led the study.
Many women with breast cancer that has not spread far can have what is known as a lumpectomy, to take out only the tumor and surrounding tissue and save most of the breast.
This is usually followed by a course of daily radiation therapy to kill any cancer cells that may remain.
The study affirms British findings published in March.
In a second study presented at the meeting, Dr. Peter Beitsch and colleagues at Medical City Dallas Hospital in Texas tested an approach called accelerated partial breast irradiation.
It uses little radioactive "seeds" implanted in the region after a tumor has been removed. It worked as well as standard radiation among 400 women followed for four years.
"Not only does it make radiation treatment much more convenient, it may actually increase the rate of breast conservation, since some women choose mastectomy because they live too far from a radiation center and cannot afford the time and expense of six to seven weeks of living or traveling to the center," Beitsch said in a statement.
Breast cancer is the leading cause of cancer death among women worldwide, according to the American Cancer Society, which estimated that about 465,000 women died from it globally in 2007.