A 45-year-old woman with BRCA1 pathogenic variant and biopsy-confirmed lobular carcinoma in situ in the right breast refuses prophylactic mastectomy. Which chemoprevention agent is LEAST effective in BRCA1 mutation carriers with LCIS?
- A Raloxifene
- B Tamoxifen ✓
- C Anastrozole
- D Exemestane
Explanation
BRCA1-associated breast cancers are predominantly ER-negative and triple-negative; therefore, tamoxifen (which acts via the oestrogen receptor pathway) is substantially less effective as chemoprevention in BRCA1 carriers compared to BRCA2 carriers or sporadic cases. Aromatase inhibitors (anastrozole, exemestane) have shown efficacy in postmenopausal high-risk women and are not limited by BRCA1 ER-negativity in the same way. Raloxifene is also ER-dependent but the marked reduction seen in BRCA1 carriers is particularly poor for tamoxifen compared to other ER-acting agents in this context.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.