Types of Cancer » Breast Cancer

breast cancer (brest KAN-ser) Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

breast cancer in situ Abnormal cells that are confined to the ducts or lobules in the breast. There are two forms, called ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS).

breast Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.

breast density Describes the relative amount of different tissues present in the breast. A dense breast has less fat than glandular and connective tissue. Mammogram films of breasts with higher density are harder to read and interpret than those of less dense breasts.

breast duct endoscopy A method used to examine the lining of the breast ducts to look for abnormal tissue. A very thin, flexible, lighted tube attached to a camera is inserted through the nipple, and threaded into the breast ducts deep in the breast. Tissue and fluid samples may be removed during the procedure.

Breast Imaging Reporting and Data System BI-RADS. A method used by radiologists to interpret and report in a standardized manner the results of mammography, ultrasound, and MRI used in breast cancer screening and diagnosis.

breast implant A silicone gel-filled or saline-filled sac placed under the chest muscle to restore breast shape.

breast reconstruction Surgery to rebuild the shape of the breast after a mastectomy.

breast self-exam An exam by a woman of her breasts to check for lumps or other changes.

breast-conserving surgery An operation to remove the breast cancer but not the breast itself. Types of breast-conserving surgery include lumpectomy (removal of the lump), quadrantectomy (removal of one quarter, or quadrant, of the breast), and segmental mastectomy (removal of the cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor). Also called breast-sparing surgery.

breast-sparing surgery An operation to remove the breast cancer but not the breast itself. Types of breast-sparing surgery include lumpectomy (removal of the lump), quadrantectomy (removal of one quarter, or quadrant, of the breast), and segmental mastectomy (removal of the cancer as well as some of the breast tissue around the tumor and the lining over the chest muscles below the tumor). Also called breast-conserving surgery.

stage I breast cancer The tumor is 2 centimeters or smaller and has not spread outside the breast.

stage II breast cancer Stage II is divided into stage IIA and stage IIB based on tumor size and whether it has spread to the axillary lymph nodes (the lymph nodes under the arm). In stage IIA, the cancer is either no larger than 2 centimeters and has spread to the axillary lymph nodes, or between 2 and 5 centimeters but has not spread to the axillary lymph nodes. In stage IIB, the cancer is either between 2 and 5 centimeters and has spread to the axillary lymph nodes, or larger than 5 centimeters but has not spread to the axillary lymph nodes.

stage IIA breast cancer Stage II breast cancer is divided into stages IIA and IIB. In stage IIA, (1) no tumor is found in the breast, but cancer is found in the axillary (under the arm) lymph nodes; or (2) the tumor is 2 centimeters or smaller and has spread to the axillary lymph nodes; or (3) the tumor is larger than 2 centimeters but not larger than 5 centimeters and has not spread to the axillary lymph nodes.

stage IIB breast cancer Stage II breast cancer is divided into stages IIA and IIB. In stage IIB, (1) the tumor is larger than 2 centimeters but not larger than 5 centimeters and has spread to the axillary (under the arm) lymph nodes; or (2) the tumor is larger than 5 centimeters but has not spread to the axillary lymph nodes.

stage III breast cancer Stage III is divided into stages IIIA and IIIB. In stage IIIA breast cancer, the cancer (1) is smaller than 5 centimeters (2 inches) and has spread to the lymph nodes in the armpit, which have grown into each other or into other structures and are attached to them; or (2) is larger than 5 centimeters and has spread to the lymph nodes in the armpit. In stage IIIB breast cancer, the cancer (1) has spread to tissues near the breast (skin, chest wall, including the ribs and the muscles in the chest); or (2) has spread to lymph nodes inside the chest wall along the breast bone.

stage IIIA breast cancer Stage III breast cancer is divided into stages IIIA, IIIB, and IIIC. In stage IIIA, (1) no tumor is found in the breast, but cancer is found in axillary (under the arm) lymph nodes that are attached to each other or to other structures; or (2) the tumor is 5 centimeters or smaller and has spread to axillary lymph nodes that are attached to each other or to other structures; or (3) the tumor is larger than 5 centimeters and has spread to axillary lymph nodes that may or may not be attached to each other or to other structures.

stage IIIB breast cancer Stage III breast cancer is divided into stages IIIA, IIIB, and IIIC. In stage IIIB, the cancer may be any size, has spread to tissues near the breast (the skin or chest wall, including the ribs and muscles in the chest), and may have spread to lymph nodes within the breast or under the arm.

stage IV breast cancer Cancer has spread to other organs of the body, most often the bones, lungs, liver, or brain.

cutaneous breast cancer Cancer that has spread from the breast to the skin.