If you've been diagnosed with breast cancer, you’ll want to know what stage it is. The answers will help you and your doctors know more about what’s ahead and decide on your treatments.
Doctors have many ways to find out what stage of breast cancer you have. Clues come from physical exams, biopsies, X-rays, bone scans and other images, and blood tests. A doctor called a pathologist puts tissue samples from the breast and lymph nodes under the microscope to find out even more.
Based on these findings, doctors string together letters and numbers to assign a stage to every case of breast cancer. It may seem like a strange code, but it’s really just a way to pinpoint exactly what’s going on with your cancer. Think of it like this: The longer the list of letters and numbers, the more exact the diagnosis and the more precise the treatment plan.
Breast Cancer Stages
The stages are the number zero and the Roman numerals I, II, III, or IV (often followed by A, B, or C). In general, the higher the number, the more advanced the cancer. But there’s more to it than that.
Stage 0. The cancer has been diagnosed early. It started in the breast ducts or milk glands and has stayed there. You’re likely to hear or see the words in situ, meaning “in the original place.”
Stage I. Starting at this level, breast cancer is called invasive, meaning it has broken free to attack healthy tissue.
Stage 1A means the cancer has spread into the fatty breast tissue. The tumor itself is no larger than a shelled peanut, or there may be no tumor
Stage IB means some cancer cells, but just tiny amounts, have been found in a few lymph nodes.
Stage II. The cancer has grown, spread, or both.
IIA means the tumor in the breast is still small, if there's one at all. There may be no cancer in the lymph nodes, or it may have spread to as many as three.