Triple-negative breast cancer (TNBC) describes breast cancer cells that do not have estrogen, progesterone, or HER2 receptors. TNBC makes up approximately 10-15 percent of all breast cancers and is usually more aggressive than the other two types, estrogen receptor-positive breast cancer and HER2-positive breast cancer.
TNBC cases are often found in younger women (under 40 years old) and in women of African American or Hispanic background. The disease may also be associated with having an inherited mutation in the BRCA1 gene.
Physicians with Dana-Farber's Susan F. Smith Center for Women's Cancers Breast Oncology Program typically treat TNBC with chemotherapy, specifically the platinum chemotherapy drug Cisplatin, which damages cancer cells' DNA and stops them from dividing. Eribulin, a newer form of chemotherapy, has also been used to treat TNBC.
Although these chemotherapy treatments are effective for TNBC, targeted treatments, such as Herceptin or tamoxifen are not. This is because TNBC lacks three molecules that exist in other types of breast cancer that are the "targets" for Herceptin or tamoxifen. However, researchers at Dana-Farber/Brigham and Women's Cancer Center (DF/BWCC) have discovered some molecular targets for TNBC drug therapy, including the Jak2/Stat3 pathway. They are also actively studying other therapies for TNBC, including the use of PARP inhibitors, PI3 kinase inhibitors and angiogenesis inhibitors. Clinical trials at DF/BWCC are currently underway to investigate these treatments.
To learn more about current and future treatments for triple-negative breast cancer, view this Targeting Triple-Negative Breast Cancer blog post and presentation from Erica Mayer, MD, MPH, or this What's New in Metastatic Research and Clinical Trials: ER Positive and Triple-Negative Breast Cancer presentation from Nancy Lin, MD, both medical oncologists with the Susan F. Smith Center for Women's Cancers at Dana-Farber.