A 52-year-old postmenopausal woman has completed five years of adjuvant tamoxifen for oestrogen receptor positive breast cancer. She presents with postmenopausal vaginal bleeding. Long-term tamoxifen therapy is associated with an increased risk of which malignancy?
- A Cervical squamous cell carcinoma
- B Ovarian serous cystadenocarcinoma
- C Endometrial adenocarcinoma ✓
- D Vulvar squamous cell carcinoma
Correct answer: C. Endometrial adenocarcinoma
Explanation
Tamoxifen is an oestrogen antagonist in breast tissue but a partial agonist in the endometrium, where sustained stimulation promotes endometrial hyperplasia and adenocarcinoma. Any postmenopausal bleeding on tamoxifen mandates endometrial evaluation. Venous thromboembolism is the other major long-term risk. Its agonist action is confined to endometrium, liver and bone, and it does not increase ovarian, cervical or vulvar cancers.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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