Tamoxifen predisposes to :
**Core Concept**
Tamoxifen is a selective estrogen receptor modulator (SERM) used primarily in the treatment and prevention of breast cancer. It acts as an estrogen receptor antagonist in breast tissue, thereby inhibiting the growth of estrogen receptor-positive tumors.
**Why the Correct Answer is Right**
Tamoxifen has a dual mechanism of action, acting as an estrogen receptor antagonist in breast tissue and an estrogen receptor agonist in other tissues such as bone, liver, and endometrium. This leads to an increased risk of endometrial cancer, deep vein thrombosis, and pulmonary embolism due to its agonist effects on the estrogen receptors in these tissues.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while tamoxifen does have a risk of inducing thromboembolic events, it is not the most accurate answer choice.
**Option B:** This option is incorrect because tamoxifen is not primarily known for its association with this condition.
**Option C:** This option is incorrect because tamoxifen is not primarily known for its association with this condition.
**Clinical Pearl / High-Yield Fact**
Tamoxifen's agonist effects on estrogen receptors in tissues such as bone and liver lead to an increased risk of osteoporosis and liver toxicity, respectively. It is essential to monitor patients on tamoxifen for these potential side effects.
**Correct Answer: B. Endometrial cancer.**