TBCRC-059: ETHAN: A phase II study comparing different Endocrine THerapies for mAle breast caNcer

This research study is looking to see 1) how well your breast cancer responds to preoperative treatment with endocrine therapy and 2) which endocrine therapy regimen is the most effective treatment for male breast cancer. The study includes a 3-week window phase containing endocrine therapy followed by a 4-month treatment phase where participants are treated with one of four endocrine therapy treatment combinations.