Radiation therapy combined with hormone therapy after surgery is more effective in keeping the breast cancer from returning

The current standard of care for early-stage breast cancer is breast conserving surgery (lumpectomy) to remove the tumor followed by radiation and hormone therapy to kill any remaining cells.

Physicians in Austria tested whether patients were more likely to have their cancer return if radiation therapy was removed from the mix. They found that radiation therapy combined with hormone therapy after surgery is more effective in keeping the cancer from returning, according to a study presented October 17, 2005, at the American Society for Therapeutic Radiology and Oncology's 47th Annual Meeting in Denver.

The study, conducted between 1996 and 2004, enrolled 869 women into the Austrian Breast and Colorectal Cancer Study Group. The patients were randomly split into two groups: one receiving whole breast radiation therapy (with a boost to the tumor bed) plus hormone therapy (either Tamoxifin or Arimidex) after surgery and one receiving only hormone therapy following surgery.

The results show a significant reduction in cancer returning in the breast among the patients who received radiation. Only one relapse in the radiation/hormone therapy group was observed compared with 13 relapses in the hormone therapy only group. Although the radiation therapy helped prevent the breast cancer from returning, researchers found patients in both groups lived just as long and were just as likely to have the cancer spread to other parts of the body.

"The overall survival rate was excellent at 97 percent. Although the overall survival rate for both patients was unchanged, radiation therapy as part of the post-lumpectomy regimen prevents the recurrence of cancer in the breast by almost 100 percent," said Richard Poetter, M.D., lead author of the study and a radiation oncologist at the University Clinic for Radiotherapy and Radiobiology in Vienna, Austria. "It seems that the current standard of care of surgery followed by radiation and hormone therapy is the best treatment for women with early-stage breast cancer."