Taking hormone therapy drugs for additional five years improves outcomes in breast cancer patients

Breast cancer patients significantly benefit by taking hormone therapy drugs called aromatase inhibitors for an additional five years, according to a major study presented at the Plenary Session of the American Society of Clinical Oncology annual meeting in Chicago and published in the New England Journal of Medicine.

Loyola University Medical Center is among the centers funded by the National Cancer Institute that enrolled patients in the trial. "This will have enormous implications for thousands of women with breast cancer," said Kathy S. Albain, MD, FACP, FASCO, principal investigator for the Loyola site. "It will change practice standards worldwide." The trial included postmenopausal women with early-stage breast cancer. Some of the women had taken anti-estrogen therapy with aromatase inhibitors for five years. Other women in the study had taken the anti-estrogen drug tamoxifen for five years, followed by five years of aromatase inhibitors. The study found that in both groups, extending the use of aromatase inhibitors for an additional five years significantly improved the amount of time the women lived without their cancer returning. "This is the first time ever that we have proof that taking anti-estrogen therapy for five years longer than the usual five-to-ten years makes a big difference in breast cancer outcomes," Dr. Albain said. The study was led by the Canadian Cancer Trials Group.