Stages of Breast Cancer
Most breast cancer is a type of carcinoma (cancer of epithelial cells, which line tissues in the body) that starts in either the ducts that lead milk to the nipple (most common) or in the lobules, where milk itself is produced, according to Medline Plus. To help diagnose and treat breast cancer (and other cancers), the progression of the disease is broken down into stages.
In order to determine the stage of a cancer, doctors use a system called TNM, according to BreastCancer.org and the American Cancer Society. In this system, "T" stands for the size of the tumor, "N" stands for whether or not the lymph nodes are affected and "M" stands for metastasis.
Stage 0
Stage 0 breast cancer is also known as ductal or lobular carcinoma in situ (DCIS or LCIS), according to the Medline Plus and BreastCancer.org. It is called "in situ" (Latin for "in place") because it has not moved (metastasized) to areas beyond where it started; for the same reason, these cancers are also referred to as non-invasive.
Stage I
Stage I breast cancer is invasive because it has moved into another area of tissue. According to BreastCancer.org, an invasive breast cancer is stage I if the tumor is 2 centimeters or less and if there is no lymph-node involvement (the cancer has not spread to the lymph nodes).
Stage II
Stage II breast cancer is broken down into two more stages, IIA and IIB. In stage IIA, there is no cancer found in the breast but cancer cells are found in the nearby lymph nodes (under the arm), or there is a tumor 2 centimeters or smaller that has spread to lymph nodes. IIA also includes a tumor sized between 2 and 5 centimeters in the breast but it has not spread to the lymph nodes.
In stage IIB, a tumor is between 2 and 5 centimeters and has spread to the lymph nodes or is bigger than 5 centimeters but has not spread to the lymph nodes, according to BreastCancer.org.
Stage III
Stage III breast cancer is broken into three further stages. In stage IIIA, there may be no cancer found in the breast, but there are cancer cells in clumped arm lymph nodes and perhaps in the lymph nodes by the breastbone. IIIA also includes tumors that may be greater or lesser than 5 centimeters which have spread to clumping arm lymph nodes.
In stage IIIB, a tumor can be any size if it has spread to the chest wall or breast skin and has spread to clumping arm lymph nodes or lymph nodes around the breast bone. Inflammatory (causing inflammation) breast cancer is staged at IIIB or higher.
In breast cancer stage IIIC, there may or may not be evidence of cancer in the breast, but if it is present it may be any size and will have spread to the chest wall or skin of the breast as well as the lymph nodes around the collarbone or the lymph nodes of the arm and breastbone, according to BreastCancer.org.
Stage IV
The last stage of breast cancer is stage IV. This occurs when the cancer has metastasized to other parts of the body, such as bone, the brain, the liver or the lungs, according to BreastCancer.org.
Tags: lymph nodes, breast cancer, spread lymph, spread lymph nodes, Stage breast, Stage Stage, Stage Stage breast
