Question: What are the different stages of breast cancer?
Answer: There are five stages of breast cancer, numbered 0 to IV.
The first stage, Stage 0, means that the breast cancer is completely confined to the ducts (or the plumbing system) of the breast, or to the lobules (the milk factory part of the breast). And if breast cancer is confined to the ducts or the lobules, we call that Stage 0 or 'in situ' cancer, which means 'in place.' It hasn't yet invaded or become life-threatening.
Now Stage I breast cancers are small cancers, less than two centimeters in size, that do invade the surrounding breast tissue, but have not spread beyond the breast.
Stage II breast cancers are tumors that are larger than 2 centimeters in size in the breast, or tumors that have spread to the lymph nodes under the arm.
Stage III tumors are tumors that are larger than 5 centimeters, which is about 2 inches, and they may or may not involve the lymph nodes under the arm.
And finally, Stage IV breast cancer is metastatic breast cancer, or cancer that has left the breast and spread to other body organs, like lung or liver or bone.