Breast Cancer

There are many types of breast cancer. The most common types are ductal carcinoma in situ, invasive ductal carcinoma, and invasive lobular carcinoma.

The type of breast cancer is determined by the specific cells in the breast that are affected. Most breast cancers are carcinomas. Carcinomas are tumors that start in the epithelial cells that line organs and tissues throughout the body. Sometimes, an even more specific term is used. For example, most breast cancers are a type of carcinoma called adenocarcinoma, which starts in cells that make up glands (glandular tissue). Breast adenocarcinomas start in the ducts (the milk ducts) or the lobules (milk-producing glands).

There are other, less common, types of breast cancers, too, such as sarcomas, phyllodes, Paget disease, and angiosarcomas which start in the cells of the muscle, fat, or connective tissue.

Sometimes a single breast tumor can be a combination of different types. And in some very rare types of breast cancer, the cancer cells may not form a lump or tumor at all.

When a biopsy is done to find out the specific type of breast cancer, the pathologist will also check if the cancer has spread into the surrounding tissues. The following terms are used to describe the extent of the cancer:

• • In situ breast cancers have not spread.

  • Invasive or infiltrating cancers have spread (invaded) into the surrounding breast tissue.

http://www.cancerresearchuk.org/about-cancer/breast-cancer?dclid=CI-63u3sidsCFUXhGwodCdsCkA

https://www.macmillan.org.uk/information-and-support/breast-cancer