Stages of breast cancer

Learn what breast cancer stages mean


Content provided by Cancer Therapy & Research Center

Accurate assessment of the extent of disease, or Stage, at the time of diagnosis, is one determinant of prognosis or risk of future recurrence of the cancer, and also determines ideal initial treatment. Thus, the Stage of breast cancer only applies to the extent of cancer at first diagnosis and the stage does not change over time. Any recurrence of cancer after initial treatment is simply called recurrence or metastasis.

The Stage of breast cancer can be a clinical stage, (the extent of breast cancer as determined purely by examination of the patient at the bedside or with basic mammograms or scans), or pathological stage referring to the establishment of extent of the cancer after surgery as determined by microscopic examination of the tissue removed at surgery.

For ideal standardization of the Stage of most cancers, and breast cancer in particular, the standard system (called the TNM system) uses the terms T for extent of the primary tumor, N for the extent of involvement of the neighboring lymph nodes, and M for the presence or absence of distant-site spread of the disease, also called, Metastases. For example, small primary tumors in the breast are staged as T1 and very large tumors are T4; few neighboring nodes are N1 and if extensive lymph nodes are N3. If any evidence of cancer is found at distant sites, the term, M1 is used. So, T1N0M0 denotes early stage cancer or Stage-I, whereas, a T1N1M1 cancer is a Stage-IV.

For more information, click here.

Anand B. Karnad, MD, Professor of Medicine, is the Castella Endowed Chair in Aging, Division of Hematology-Oncology, Department of Medicine, The University of Texas Health Science Center San Antonio.