Exemestane is an oral steroidal aromatase inhibitor used to treat some types of breast cancer such as hormone-receptor- positive type. It also prevents any recurring cancer of this type. Likewise, it treats to what happens to women after the menopausal period. It decreases the amount of estrogen which sometimes contribute increase of breast cancers. Exemestane helps reverse the growth of these cancers or slow down the growth. There has been no detectable effect on the adrenal biosynthesis of corticosteroids. Accordingly, this reduction in tumor concentrations of estrogen delays tumor growth and disease progression.