Breast Cancer Stages: The Numbers, The Letters, And The LingoKatie Taylor
Understanding a breast cancer diagnosis can feel a bit like learning a new language. Ductal Carcinoma In Situ, Tubular Carcinoma, Paget’s Disease of the Breast… and then of course there are different stages for each type, and different systems that doctors use to talk about the stages. You may start to feel like you’re ordering something from an auto-parts store: “Yes, I have a stage 2 invasive papillary carcinoma and I’m looking for a partial mastectomy with sentinel lymph node dissection as well as external beam radiation therapy. Do you have that in stock?”
Let’s break it down step by step. Here we’ll talk about how the stages of cancer are determined, the traditional numbers staging system versus the TNM system, and the definitions of some common cancer-related terms.
The Staging Process
The staging process gives your medical team a common language to accurately describe a specific person’s cancer and quickly understand its progression and prognosis. Breast cancer is assigned a stage 0 through IV, and the stage is determined by the size of the tumor, if the cancer is invasive or non-invasive, if the cancer has spread to the lymph nodes, and if the cancer has spread to other parts of the body.
Stage 0 cancer is also called “carinoma in situ”; the term in situ means that the cancer hasn’t spread from its original origin. Stage 0 may or may not ever become invasive. The three possible types of stage 0 are: ductal carcinoma in situ (DCIS), lobular carcinoma in situ (LCIS), and Paget disease of the nipple.
DCIS is the most common stage 0 cancer. In DCIS, non-invasive abnormal cells have been detected in the lining of the milk ducts, but have not yet spread. Some patients choose active surveillance instead of surgery as treatment, and the five-year survival rate for stage 0 is close to 100 percent.
LCIS is not usually considered cancer as it describes a growth of abnormal, non-invasive cells contained in the ducts or lobules of the breasts.