Most women are aware of a link between estrogen and breast cancer. Yet, there are three types of breast cancer: ductal (80%), lobular (10%), and inflammatory (1% to 5%), all of which have different receptor characteristics that guide treatment. Approximately 75% of breast cancer is estrogen-receptor (ER) positive. However, there are conditions in which estrogen both fuels and, at other times, kills ER-positive breast cancer cells. One type of breast cancer does not even recognize estrogen at all. It is estimated that in 2015, there will be 231,840 new cases of breast cancer and 60,290 cases of breast carcinoma in situ. And it is predicted that 40,290 women will die of this disease (cancer.org). Understanding the types of breast cancer offers promise for improved surveillance, prevention, and more effective treatments.