In order to initiate appropriate treatment for a patient diagnosed with breast cancer, the stage of the cancer should be well known. For this reason, staging tests are applied after diagnosis. The stage of the cancer is the determination of whether the cancer is confined to the breast or whether it has spread.
Tests used in breast cancer staging:
Ultrasound: Information can be obtained whether breast cancer has spread especially to the lymph nodes.
Chest X-ray : It gives an idea about whether the breast cancer has spread to the lung.
PET/CT: The whole body is scanned by giving a harmless protein, which is a special sugar. Along with the breast, there is involvement in other lymph nodes, organs and tissues where cancer cells spread, if any. It gives detailed information about the spread of breast cancer.
Bone scan: Used to evaluate the bones most at risk of metastasis from breast cancer.
Magnetic Resonance Imaging (MR): It gives an idea about the breast tissue and surrounding lymph nodes.
Breast cancer stages:
TNM classification is used in the determination of breast cancer stages as in other cancer types. The T value indicates the size of the tumor, the N value indicates the involvement of the surrounding lymph nodes, and the M value indicates whether there is spread to other organs and tissues.
T0: No tumor,
Tis: Carcinoma in situ (Paget’s Disease etc.),
T1: There is a tumor 2 cm or smaller,
T2: There is a 2-5 cm tumor,
T3: There is a tumor larger than 5 cm,
T4: There is a tumor growing in the chest wall or skin.
N0: Cancer cells have not spread to surrounding lymph nodes,
N1: 1-3 lymph nodes are involved in the armpit,
N2: 4-9 lymph nodes are involved under the armpit.
N3: Ten or more lymph nodes are involved in the armpit or lymph nodes around the collarbone are involved.
M0: No distant organ spread,
M1: There is spread to distant organs (bones, lung, brain, liver, etc.).
Stage is determined according to TNM values.
Breast cancer stages:
Stage 0: Carcinoma in situ
Stage 1: The tumor is smaller than 2 cm, limited to the breast, axillary lymph nodes are not affected.
Stage 2: The tumor is between 2-5 cm, the cancer is limited to the breast, and the axillary lymph nodes are involved.
Stage 3: The tumor is between 2-5 cm, axillary lymph nodes are involved, adherent to breast skin or tissues, no spread to other organs,
Stage 4: The cancer has spread to other regions.
Breast cancer grades:
It shows the growth and spread rate of breast cancer. In the pathology report, it is indicated by a score between 3 and 9, which indicates the degree of breast cancer. The lower the score, the lower the rate of spread of the cancer.
- Well differentiated (grade 1) (3,4.5 points on pathology report): Very slow growing, slow spreading.
- Moderately differentiated (grade 2) (6.7 points on pathology report): It grows and spreads moderately.
- Poorly differentiated (grade 3) (8.9 points on pathology report): Grows fast, spreads quickly.