What is stage 1 breast cancer?

Stage 1 breast cancer is the earliest form of invasive breast cancer. At stage 1, the cancer cells start spreading beyond the primary site of origin and into the surrounding area of breast tissue, and in very small traces into the lymph nodes in some cases. Stage 1 tumors are small and therefore difficult to detect. But with a combination of regular self exams and screening (with mammograms), stage 1 breast cancer can be detected early and treated well. When the cancer starts spreading to other healthy parts of the breast tissue, it is called stage 1 breast cancer. Stage 1 breast cancer is invasive. There are two sub-categories to stage 1:

At stage 1A: The tumor is smaller than 2 centimeters across. It has not spread outside the breast, and no lymph nodes are involved.

At stage 1B: There is either no tumor, or the tumor is less than 2 centimeters in size. In this stage, small clusters of breast cancer cells are found in the lymph nodes.

Treatment for stage 1 breast cancer (see full article for early breast cancer treatment)

At stage 1, treatment usually involves breast conserving surgery (lumpectomy plus surgical axillary lymph node staging), followed by chemotherapy and radiation treatment.

Chemotherapy in stage 1 breast cancer depends on the size and other factors.

See also:

Stage 0 breast cancer
Stage 2 breast cancer
Stage 3 breast cancer
Stage 4 breast cancer


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