**Question:** A 58-year-old postmenopausal woman on estrogen replacement complains of recent onset of spotting. A bimanual pelvic examination is unremarkable. Most likely diagnosis?

A. Endometrial hyperplasia
B. Endometrial cancer
C. Ovarian cyst
D. Pelvic inflammatory disease

**Core Concept:** In postmenopausal women, estrogen replacement therapy increases the risk of endometrial hyperplasia and endometrial cancer due to unopposed estrogen receptor stimulation without progesterone receptor stimulation.

**Why the Correct Answer is Right:** The correct answer is endometrial cancer (option B) because:

- Estrogen replacement in postmenopausal women can lead to unopposed estrogen receptor stimulation without progesterone receptor stimulation.
- This imbalance can result in endometrial hyperplasia and subsequently, endometrial cancer.
- The patient's age (58 years) and history of estrogen replacement further support this diagnosis.

**Why Each Wrong Option is Incorrect:**

A. Endometrial hyperplasia: Although endometrial hyperplasia can occur in postmenopausal women on estrogen replacement, the unremarkable bimanual pelvic examination makes this option less likely.

B. Endometrial cancer: The unremarkable bimanual pelvic examination is less specific, making a diagnosis of endometrial cancer less certain.

C. Ovarian cyst: An unremarkable pelvic examination is inconsistent with this diagnosis.

D. Pelvic inflammatory disease: The unremarkable pelvic examination rules out this diagnosis.

**Core Concept:** Bimanual pelvic examination is a fundamental part of the physical examination in gynaecology and is crucial for diagnosing conditions involving the uterus and ovaries.

**Clinical Pearls:**

1. Bimanual pelvic examination involves inspecting, palpating, and percussing the abdomen, pelvic organs, and genitalia for any abnormalities.
2. In postmenopausal women, a normal bimanual pelvic examination is essential for excluding conditions like pelvic inflammatory disease, ovarian cysts, and fibroids.
3. While an unremarkable examination can help to rule out these conditions, it does not exclude the possibility of endometrial hyperplasia and cancer, highlighting the importance of considering the patient's history and other diagnostic tests like ultrasound or biopsy for a definitive diagnosis.

**Why the Correct Answer is Right:** In this case, the unremarkable physical examination makes endometrial cancer (option B) the most likely diagnosis.

**Why Each Wrong Option is Incorrect:**

A. Endometrial hyperplasia: Although endometrial hyperplasia can be associated with estrogen exposure, an unremarkable examination rules out this diagnosis, making it less likely.

B. Endometrial cancer: The unremarkable examination is consistent with this diagnosis, as endometrial cancer can occur without abdominal or vaginal bleeding, which is typically associated with endometrial