Breast Cancer Staging

Breast Cancer Stage

Once a person is determined to have a malignant tumor or the diagnosis of breast cancer, the healthcare team will determine staging to communicate how far the disease has progressed. Knowing the stage helps determine the best way to contain and eliminate the breast cancer.

TNM System Of Staging

The most widely used method of staging breast cancer is the TNM system.

TNM stands for:

  • T = Tumor size
  • N = Lymph node status (the number and location of lymph nodes with cancer)
  • M = Metastases (whether or not the cancer has spread to other areas of the body)

In the past, tumor stage was classified with these 3 measures only. Starting in 2018, the TNM system added these measures:

  • Tumor grade
  • Estrogen-receptor status
  • Progesterone-receptor levels in the tumor tissue
  • HER2/neu status
  • Menopausal status
  • General health of the patient

For more information about the TNM classifications for each stage of breast cancer, click here.

If you were diagnosed before 2018, please refer to this staging information.

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