Question: What does triple negative mean regarding breast cancer? My doctor told me that all of the special studies the lab performed on my tumor were negative and that means it can be a more aggressive type of cancer.
Answer:  Triple negative means that the three main studies that pathologists perform on any invasive breast cancer (estrogen receptor, progesterone receptor, and HER2) were all negative. Since the hormone receptors on your cancer are negative you would not qualify to take endocrine therapy (such as Tamoxifen) nor would you qualify for drugs like Herceptin since the HER2 test was also negative.  Studies have shown that these types of cancer can be more aggressive than others, but also may respond well to certain chemotherapies.