CYP19A1 and breast neoplasm: breast neoplasms/radiotherapy[mh] AND breast neoplasms/surgery[mh] AND (breast neoplasms/drug therapy[mh] OR antineoplastic agents, hormonal[mh] OR tamoxifen[mh] OR aromatase inhibitors[mh]) AND ((concurrent*[tw] OR concomitant*[tw]) AND sequential*[tw]).