In a premenopausal woman with a 6 × 4 mm vascularized endometrial lesion (overall thickness 7.6 mm) and no abnormal uterine bleeding, what is the likelihood of malignancy and what is the recommended management?

Management of Vascularized Endometrial Lesion in Premenopausal Woman Without Bleeding

In a premenopausal woman without abnormal uterine bleeding, endometrial thickness is NOT a reliable indicator of malignancy, and the presence of a small vascularized focal lesion (6 × 4 mm) with overall thickness of 7.6 mm does not warrant routine intervention. 1

Risk of Malignancy in This Clinical Context

The likelihood of malignancy is extremely low in this scenario for several key reasons:

• Endometrial thickness varies physiologically throughout the menstrual cycle in premenopausal women, and there is no validated absolute upper limit cutoff 1
• Endometrial thickness is NOT a reliable indicator of endometrial pathology in premenopausal women 1
• Even focal lesions with vascularity in asymptomatic premenopausal women have very low malignancy rates, with studies showing that in women without abnormal uterine bleeding, the negative predictive value for excluding focal pathology at thickness <5.2 mm approaches 99% 2
• The absence of abnormal uterine bleeding is the most critical protective factor, as approximately 90% of endometrial cancer patients present with abnormal bleeding 3

Recommended Management Algorithm

Initial Approach: Observation

• Clinical symptoms, rather than thickness alone, should drive further evaluation in premenopausal women 1
• The American College of Radiology recommends focusing on abnormal echogenicity and texture rather than absolute thickness measurements in premenopausal women 1
• No immediate intervention is required for this incidental finding in an asymptomatic patient 1

When to Consider Further Evaluation

Endometrial sampling should be considered based on risk factors for endometrial cancer rather than thickness measurements 1:

• Age >45 years 1
• Obesity 1
• Unopposed estrogen exposure 1
• Development of abnormal uterine bleeding 4

If Further Characterization is Desired

• Sonohysterography can distinguish between focal lesions (polyps) and diffuse pathology with 97% accuracy 5
• Sonohysterography features suggesting a benign endometrial polyp include: intact myometrial-endometrial interface, single vessel, acute angle with endometrium, and homogenous echogenicity 5
• However, sonohysterography cannot distinguish between benign endometrial pathology and endometrial cancer with high certainty 5

Critical Pitfalls to Avoid

• Do NOT apply postmenopausal endometrial thickness thresholds to premenopausal women, as the physiology is fundamentally different 1
• Do NOT perform routine endometrial sampling based solely on thickness or presence of small focal lesions in asymptomatic premenopausal women 1
• The absence of vascularity on Doppler does not exclude pathology, but the presence of vascularity does not confirm malignancy 1
• Currently, there are no definitive studies demonstrating whether Doppler can differentiate between benign and malignant endometrial lesions 5

Follow-Up Strategy

• Educate the patient to report any development of abnormal uterine bleeding promptly 1
• If the patient develops abnormal bleeding, proceed with transvaginal ultrasound with Doppler to assess for structural abnormalities, and consider endometrial sampling based on risk factors 1
• Repeat imaging may be considered if clinical concern develops, but routine surveillance imaging is not indicated for asymptomatic findings 1