Lobular carcinoma in situ (LCIS) is a condition where abnormal cells are found in the lobules of the breast, which are the glands that produce milk. Although it is not considered breast cancer, LCIS indicates an increased risk of developing breast cancer in the future. It is usually detected during a biopsy for another issue, as it often does not cause any noticeable symptoms. LCIS is classified as a non-invasive condition, meaning the abnormal cells have not spread beyond the lobules. Treatment options may include regular monitoring, lifestyle changes, or preventive measures, depending on individual risk factors and preferences.