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Triple Negative Breast Cancer (TNBC) | Tigerlily Foundation – If a breast cancer is ER-negative, PR-negative and HER2-negative, it is then known as Triple Negative Breast Cancer (TNBC). 

If a breast cancer is ER-negative, PR-negative and HER2-negative, it is then known as Triple Negative Breast Cancer (TNBC).

What is Triple Negative Breast Cancer (TNBC)?

This type of cancer is determined by a pathology report; it means that you have tested negative for estrogen receptors (ER-), progesterone receptors (PR-) and HER2 (HER2-). This type of cancer accounts for about 10-20% of all cancers. These results mean that your cancer is not supported by the hormones estrogen and progesterone, and is not supported by having too many HER2 receptors. As a result, this type of cancer cannot be treated by hormonal therapy or by HER2-targeting therapy. Other types of treatments are used to fight triple negative cancer.


When I was diagnosed with triple negative breast cancer (TNBC), I felt alone, I was scared, it was the fight of my life that changed me as a person from that moment forward.  It was that feeling of being scared, alone, not having targeted treatments for a disease that could come back at any time.  Seeing so many of my metastatic friends go through unimaginably difficult treatments and the many friends who have lost their life to TNBC. I have spent the last 17 years working to change this outcome.

I have witnessed how TNBC can be more aggressive. It grows and spreads faster, it has fewer treatment options and can have a worse prognosis (outcome), especially for Patients of Color.  When I was diagnosed, I did not see anyone who looked like me. There was no community or advocates that were similar in age, I did not see advocates that were Black or Brown, Patients of Color that I could connect with.  Creating Tigerlily Foundation is my way of supporting all patients after me so they will not feel alone and scared. I dreamed of a future when TNBC and breast cancer would become curable diseases with many targeted treatments designed for Patients of Color and patients of all backgrounds. In this dream treatments are easily accessible; with no barriers to lifesaving cancer treatments.

~ Maimah Karmo, President and Chief Unicorn, Tigerlily Foundation

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