Question: I am confused about my pathology report which says my cancer is invasive ductal carcinoma, estrogen receptor negative (less than 10% of cells) and progesterone negative (0% of cells). Why does it say less than 10% for estrogen receptor is negative? Doesn’t that mean some cells are positive? My doctor said since I am negative I don’t qualify for Tamoxifen.

Answer: That may not be true–from what your report says it means some of your cancer cells are expressing estrogen receptor. Many pathologists use different tests for estrogen receptor and different grading schemes for what is positive and negative. I prefer what is called the “Allred score” which is a clinically-validated test that gives a score for your tumor and has been shown to predict response to endocrine therapy. If your cancer has less than 10% positive cells that could still mean 5% were positive, and if that’s the case you could be considered estrogen receptor positive using this system. If you are interested, email me and I can provide you with some more material from the medical literature about this.