Following can cause endometrial cancer :
**Core Concept**
Unopposed estrogen stimulation can lead to endometrial hyperplasia and increase the risk of endometrial cancer. This is due to the uncontrolled proliferation of endometrial cells, which can result in genetic mutations and malignant transformation.
**Why the Correct Answer is Right**
The correct answer is an estrogen receptor agonist. Estrogen receptor agonists mimic the action of estrogen by binding to estrogen receptors in the endometrium, leading to an increase in cell proliferation. This is particularly concerning in postmenopausal women, who have a higher risk of endometrial cancer due to the unopposed estrogen stimulation. The continuous exposure to estrogen in the absence of progesterone can lead to endometrial hyperplasia and cancer.
**Why Each Wrong Option is Incorrect**
**Option A:** This is incorrect because progesterone is an estrogen receptor antagonist, which means it counteracts the effects of estrogen on the endometrium and therefore does not increase the risk of endometrial cancer.
**Option B:** This is incorrect because tamoxifen is a selective estrogen receptor modulator (SERM) that can have both estrogen agonist and antagonist effects depending on the tissue type. However, in the endometrium, tamoxifen has a net estrogen agonist effect, which can increase the risk of endometrial cancer.
**Option C:** This is incorrect because progesterone is not a known cause of endometrial cancer, and in fact, progesterone can help to counteract the effects of estrogen on the endometrium.
**Clinical Pearl / High-Yield Fact**
Tamoxifen, a commonly used SERM in breast cancer treatment, can increase the risk of endometrial cancer, particularly in postmenopausal women. This is an important consideration when prescribing tamoxifen for breast cancer treatment.
**Correct Answer: B. Tamoxifen**