MPA (also known as depo provera) is a highly potent progestational steroid that has been used worldwide as a contraceptive. There has been a concern about the possibility of an increased risk of breast cancer associated with its use. On the other hand, MPA when employed at high doses (>0.5 - 1.0g / day i.m.) can produce objective remission with improved survival in about 30?% of postmenopausal women with advanced breast cancer resistant to cytotoxic drugs and endocrine therapies. Early results suggest that the response rate can be increased in patients with estrogen and / or progesterone positive receptors.Synonyms: MPA, Medroxy Progesterone Acetate, depo provera