Endocrine Pharmacology USMLE Step 1 Practice Question
A 54-year-old postmenopausal woman with estrogen receptor-positive breast cancer was started on tamoxifen 2 years ago. She now presents with vaginal bleeding (BP 128/82, HR 82, RR 16, Temp 37°C). Pelvic ultrasound shows endometrial thickness of 12 mm with hyperechoic appearance. Endometrial biopsy confirms hyperplasia without atypia. She denies hormone replacement therapy use. Which selective estrogen receptor modulator is most likely responsible for this complication?
Answer choices
- AMifepristone
- BCombined oral contraceptive pill
- CClomiphene
- DRaloxifene
- ETamoxifenCorrect answer
- FAnastrozole
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