Management of postmenopausal women with vaginal bleeding when the endometrium can not be visualized.

Objective: To determine the risk of endometrial cancer when endometrial thickness is not visualized using ultrasonography.

Design: Cross-sectional study.

Setting: Gynecological oncology center in the United Kingdom.

Population: All postmenopausal women referred with vaginal bleeding.

Methods: All women were investigated using gray-scale transvaginal ultrasonography. Women were arbitrarily stratified into four groups according to the endometrial thickness measurement. Women with endometrial thickness that was not adequately visualized on ultrasonography were included in a separate group.

Main Outcome Measures: Endometrial cancer diagnosis.

Results: Over a 50-month period, 4454 women were investigated for postmenopausal vaginal bleeding. A total of 259 (6%) of women were diagnosed with endometrial carcinoma. Endometrial thickness measured 5-9.9 mm in 1201 (27%), 10-14.9 mm in 468 (11%), 15-19.9 mm in 209 (5%), and equal to or greater than 20mm in 197 (4%) of women. In 174 (4%) of women, the endometrial thickness was not visualized on transvaginal ultrasonography. For women where the endometrial thickness was not adequately visualized, the final histology included benign endometrium (124), endometrial cancer (26), endometrial polyps (11), endometritis (7), and other pathology (7). The odds of endometrial cancer in women where the endometrial thickness was not visualized were found to be significantly higher than the odds of cancer for women with an endometrial thickness of 5-9.9 mm (OR = 5.23, 95%CI 3.10-8.85, p-value <0.0001).

Conclusions: For women presenting with postmenopausal bleeding and where the endometrial thickness cannot be adequately visualized on ultrasonography, hysteroscopic evaluation is recommended.