Breast Pathology 2019

Lobular carcinoma In Situ

Lobular carcinoma in situ (LCIS) is an uncommon condition in which abnormal cells form in the milk glands (lobules) in the breast. LCIS isn't cancer. But being diagnosed with LCIS indicates that you have an increased risk of developing breast cancer. It begins when cells in a milk-producing gland of a breast develop genetic mutations that cause the cells to appear abnormal. The abnormal cells remain in the lobule and don't extend into, or invade, nearby breast tissue. LCIS is viewed as an uncommon condition, but we don’t know exactly how many people are affected. That’s because LCIS does not cause symptoms and usually does not show up on a mammogram. It tends to be diagnosed as a result of a biopsy performed on the breast for some other reason. It is usually diagnosed before menopause, most often between the ages of 40 and 50. Less than 10% of women diagnosed with LCIS have already gone through menopause. This is extremely uncommon in men. This is described as pleomorphic or if it has necrosis (areas of dead cells), in which case it might be more likely to grow quickly.