Estrogen receptor-positive, HER2-negative breast cancers are the most prevalent type, typically found on screening mammography, have a favorable prognosis, and peak in incidence around age 65.

“there are really three major flavors of breast cancer there is estrogen receptor positive So-Cal her2 or hr2 negative breast cancers and those are the most prevalent kinds of breast cancer um they account for 70 to 75% if not more of all breast cancers they are the tumors most likely to be found on screening mamography as opposed to presenting with a lump in the breast they tend to have ounce for ounce size for size the most favorable prognosis in most but not all instances and um they peak in incidents at around age 65 in the United States”