Breast cancer patients who have additional tissue removed during a partial mastectomy are half as likely to need a second surgery, according to a Yale Cancer Center study released today. The study could have a major impact on thousands of patients, sparing them a second operation, according to researchers. “No one likes going back to the operating room, especially not the patients who face the emotional burden of another surgery,” said Dr. Anees Chagpar, the study’s lead author, associate professor of surgery at Yale School of Medicine and director of The Breast Center, Smilow Cancer Hospital at Yale-New Haven. Nearly 300,000 women nationwide are diagnosed with breast cancer each year. Most of them have early stages of the disease, and more than half of those undergo partial mastectomies to remove the cancer, Chagpar said.