Staging

Staging is a term to describe how far cancer has spread and is used to estimate prognosis and decide on treatment. Breast cancer is first staged by doing either an axillary node dissection or a sentinel node biopsy.  The nodes are called ‘positive’ if they contain cancer cells and ‘negative’ if they do not.  Initial staging is done to determine the best treatment plan.

If cancer has spread beyond the lymph nodes then additional staging tests maybe performed to check for spread to other organs where breast cancer commonly metastasizes (lung, liver, bone).

Stage 0:

Non invasive or insitu carcinoma of the ducts or lobules, or Paget’s disease of the nipple.

Stage I:

Tumour no larger than 2 centimeters (3/4 inch) that has not spread.

Stage II:

Tumour  2-5 cm (about ¾ to 2 inches). Lymph nodes may or may not be positive for cancer. If the tumor is smaller than 2 cm but the lymph nodes are positive, cancer is also considered Stage II.

Stage III:

Tumours greater than 5 cm (2 inches) or cancer with extensive lymph node involvement or cancer spread to the upper chest but not distant metastasis.

Stage IV:

Any size tumour that has spread throughout the body and is found in a major organ.

The TNM (tumour, nodes, and metastasis) is another type of classification system and it categorizes a person’s breast cancer into one of three stages based upon:

• Tumour – The size or the tumour. This information is found on mammography, ultrasound, and pathology reports.
• Nodes - Were the lymph nodes positive or negative? And if the nodes were positive, to what extent? This information is determined by the pathology report of the axillary node dissection or sentinel lymph node biopsy.  CT
• Metastasis – Staging tests revealed spread to other organs.