Fulvestrant has been found to be as effective as the third-generation aromatase inhibitors (AIs) anastrozole and letrozole for advanced, post-menopausal, tamoxifen-resistant breast cancer, and also appears to be effective after treatment with non-steroidal AIs.[19] Based on the evidence available, for the patient we presented here, concomitant fulvestrant with irradiation was prescribed under our MDT. This evidence concerns the gene CYP19A1 and breast cancer.