The largest study ever done of breast cancer treatment finds that most women with the most common form of the disease can skip chemotherapy without hurting their chances of beating the cancer.
The results are expected to spare up to 70,000 patients a year in the United States and many more elsewhere the ordeal and expense of these drugs.
The study involved early-stage breast cancer that has not spread to lymph nodes, is fueled by hormones and is not the type targeted by the drug Herceptin.
Gene-guided testing showed that most women don't need treatment beyond surgery and hormone blockers, and chemo did not improve survival.
Results were discussed Sunday at a cancer conference in Chicago and published by the New England Journal of Medicine.