From the Guidelines
The workup for postmenopausal bleeding should begin with a thorough history and physical examination, followed by transvaginal ultrasound to measure endometrial thickness, as it is considered the first-line screening test for endometrial cancer 1.
Key Steps in the Workup
- A thorough history and physical examination to identify risk factors and guide further evaluation
- Transvaginal ultrasound (TVUS) to measure endometrial thickness, with a threshold of 4 mm or greater prompting further investigation 1
- Endometrial sampling, typically via endometrial biopsy in the office setting, for patients with an endometrial thickness greater than 4 mm or persistent bleeding despite a thin endometrium
- Hysteroscopy with dilation and curettage for patients with inadequate office biopsy samples or persistent bleeding despite negative biopsy
- Laboratory tests, including a complete blood count to assess for anemia, and thyroid function tests if clinically indicated
- Current cervical cytology (Pap smear)
Rationale
The approach is guided by the need to exclude endometrial cancer, which is associated with postmenopausal bleeding in approximately 10% of cases, as highlighted in the ESMO clinical practice guidelines for diagnosis, treatment, and follow-up of endometrial cancer 1. While the diagnostic strategy may vary, the use of transvaginal ultrasound with a cut-off point of 4 mm, followed by endometrial sampling, is supported by recent evidence 1. Risk factors such as obesity, diabetes, hypertension, tamoxifen use, and family history of endometrial or colon cancer should increase concern for malignancy and prompt thorough evaluation. Patients should be counseled on the potential need for multiple visits and surgical procedures to ensure accurate diagnosis. The choice of diagnostic steps is influenced by the high sensitivity and specificity of TVUS for detecting endometrial pathology, including cancer, and the importance of timely evaluation to improve outcomes in cases of malignancy 1.
From the Research
Initial Evaluation
The workup for postmenopausal bleeding typically begins with a thorough history and physical examination, including identification of risk factors for endometrial cancer and a medication history 2. A speculum examination should be performed to assess for atrophic changes in the vagina and to look for evidence of cervical malignancy or polyps 2.
Imaging and Biopsy
Transvaginal ultrasonography is usually sufficient for an initial evaluation of postmenopausal bleeding if the ultrasound images reveal a thin endometrial echo (less than or equal to 4 mm) 3, 4. This is because an endometrial thickness of 4 mm or less has a greater than 99% negative predictive value for endometrial cancer 3, 4.
- Key points to consider:
- Endometrial thickness measurement aims to identify which women with postmenopausal bleeding are at significant risk of endometrial cancer 2.
- If the endometrial thickness is greater than 4 mm, further testing such as endometrial biopsy or hysteroscopy may be warranted 3, 4, 5.
- Hysteroscopy with dilation and curettage may be necessary if blind sampling does not reveal endometrial hyperplasia or malignancy, especially in cases of persistent or recurrent bleeding 3, 4.
Further Testing
If the initial evaluation and imaging do not reveal a cause for the bleeding, further testing may be necessary. This can include:
- Hysteroscopy with biopsy, which is considered the gold standard for investigating the endometrial cavity, especially when focal pathology is suspected 5.
- Endometrial biopsy, which provides a histological diagnosis and can help identify endometrial hyperplasia or malignancy 2, 6.
Management
The management of postmenopausal bleeding depends on the underlying cause.