<prompt> Drug useful in breast cancer is -TamoxifenCyproteroneTestosteroneChlorambucil  <response>: Ans. is a i.e., Tamoxifen Pharmacotherapy of breast cancero Many breast carcinomas possess estrogen receptors - Estrogen promotes their growth,o Drugs which decrease the action of estrogen on breast CA by one or other mechanisms, can be used in breast CA.Drugs used in Breast cancero Selective estrogen receptor modulators SERMs - Tamoxifen, Tromifene.o Selective estrogen receptor down regulators SERDs - Fulvestranto Aromatase inhibitors - Letrozole, anastrozole, exemestoneo LHRH GnRh analogueso Aminoglutethemideo High doses progesterones - Megastrol acetate. 