A research led by Dr. Tim Whelan, a Professor of Oncology of the Michael G. DeGroote School of Medicine at McMaster University, has concluded that an intense three-week course of radiation therapy is just as effective as the standard five-week regimen, for women with early-stage breast cancer.

Dr. Whelan exclaimed that the study's results will change cancer treatment practice not just in Canada, but throughout North America and around the world.

"This is win-win: shorter intense treatment is better for the patient and less costly to provide", said Dr. Whelan.

The study involved 1,234 women with invasive breast cancer who had a lumpectomy, which involves removing the cancerous lump and a small amount of normal tissue around it. After surgery, they either had the standard radiation treatment over a 35-day period or an accelerated treatment over 22 days.

About 10 years later, the risk for local recurrence of the cancer was 6.7 percent among the women who had received standard radiation treatment and 6.2 percent among those who received the briefer treatment.

Dr. Manjeet Chadha, Associate Chairperson of Radiation Oncology at Beth Israel Medical Center in New York City, found that a three-week course of radiation works well for early-stage breast cancers.