Breast cancers are given a grade according to:
- How different the cancer cells are to normal breast cells
- How quickly they are growing
The grade of a cancer is different to the cancer stage.
A cancer’s grade is determined when a doctor (pathologist) looks at the cancer cells under a microscope, using tissue from a biopsy or after breast cancer surgery.
There are three grades of invasive breast cancer:
- Grade 1 looks most like normal breast cells and is usually slow growing
- Grade 2 looks less like normal cells and is growing faster
- Grade 3 looks different to normal breast cells and is usually fast growing
Sometimes the grade given to a cancer after a biopsy can change after surgery. This is because after surgery there’s more tissue for the pathologist to look at, which can give them more detailed information about the cancer.
Your treatment team will consider the grade of your cancer when deciding which treatment to offer you.
If you have grade 3 breast cancer, you’re more likely to be offered chemotherapy. This is to help destroy any cancer cells that may have spread as a result of the cancer being faster growing.
Chemotherapy is less likely for grade 1 and grade 2 cancers.
The grade of your cancer alone will not determine what treatment you’re offered. Your treatment team will consider the grade alongside all other information about your cancer when deciding on the best treatment options for you.
Find out more about breast cancer and prognosis.
DCIS is an early form of breast cancer.
There are three grades of DCIS, usually called low, intermediate and high.
You can find out more about grades of DCIS on our DCIS page.