The difference between breast cancer and lobular hyperplasia is as follows: Lobular hyperplasia primarily manifests as nodular lumps that can be felt within one or both breasts. These lumps vary in size, are tough but not hard, and sometimes tender to touch. The boundaries of the lumps with the surrounding breast tissue are not clear, but they are not adherent to the skin or chest muscles, sometimes presenting as areas of thickening with unclear boundaries. Breast cancer, on the other hand, appears as a solitary, painless lump that is hard as stone and can be round, oval-shaped, or irregular. It can grow large, has poor mobility, and can easily adhere to the skin and surrounding tissues. The growth of the cancerous lump is not related to the menstrual cycle or emotional changes, and it can grow rapidly in a short time. On a mammogram, breast cancer lumps may show tiny calcifications, abnormal vascular shadows, and spicules.