- Anastrozole, a potent and selective aromatase inhibitor, versus megestrol acetate in postmenopausal women with advanced breast cancer: results of overview analysis of two phase III trials. Arimidex Study Group. Buzdar, A., Jonat, W., Howell, A., Jones, S.E., Blomqvist, C., Vogel, C.L., Eiermann, W., Wolter, J.M., Azab, M., Webster, A., Plourde, P.V. J. Clin. Oncol. (1996)