They found that the use of trastuzumab produced a 37 percent improvement in survival and a 40 percent reduction in risk of cancer occurrence, compared to patients treated with chemotherapy alone. These findings, published in the Journal of Clinical Oncology, demonstrate how important trastuzumab has been to the treatment of this form of breast cancer, says the study’s lead author, Edith A. Perez, M.D., deputy director at large, Mayo Clinic Cancer Center and director of the Breast Cancer Translational Genomics Program at Mayo Clinic in Florida. “This long follow-up of patients shows that we have really altered the natural history of this disease,” says Dr…