SAN ANTONIO (EGMN) - Young women with a benign breast biopsy showing complete lobular involution are at below-average risk of future breast cancer, according to a large prospective Mayo Clinic study.This finding - that lobular involution constitutes a novel protective factor against breast cancer in young women with benign breast disease - is an important advance in the effort to better stratify breast cancer risk in the 1 million American women per year who undergo a biopsy showing benign breast...