Triple negative breast cancer (TNBC) gets its name from the fact that the cancer cells test negative for 3 different things:
Because these tumours are negative for these things, standard treatments for breast cancer, such as hormonal therapy or trastuzumab (Herceptin) cannot be used with this type of breast cancer.
Basal-like (or basal type) breast cancer has a certain genetic pattern. These cancer cells make abnormally large amounts of the protein cytokeratin5/6 and have too many epidermal growth factor receptors (EGFRs), which signal cell growth and division. In addition to this genetic pattern, basal-like breast cancers are often triple negative. To date, however, there is no internationally accepted definition for basal-like cancers, and there is no genetic test available in clinical practice to identify these tumours.
It is important to remember that triple negative breast cancer and basal-like breast cancer are not the same.
Triple negative tumours are most often invasive ductal cancers, but ductal carcinoma in situ may also be triple negative.
Women under the age of 40 and women of African or Asian ancestry are at higher risk for developing triple negative or basal-like breast cancers. Women with BRCA1 gene mutations are at higher risk of developing basal-like breast tumours that are also triple negative.
Triple negative and basal-like breast cancers also differ from other types of breast cancer:
Treatment options for triple negative and basal-like breast cancer are similar to other types of breast cancer, and may include:
Research is underway to find out:
The Canadian Cancer Society is actively lobbying the federal government to establish a national caregivers strategy to ensure there is more financial support for this important group of people.