Screening for endometrial thickness (ET) by transvaginal ultrasound (TVUS) missed more cases of endometrial cancer in Black women than in White women, according to a simulated cohort study published in JAMA Oncology.
The study authors noted that advanced stage endometrial cancer is more frequently diagnosed in Black women than in White women, regardless of insurance status or histologic subtype. Because ET screening by TVUS is commonly used to screen women for biopsy for endometrial cancer, this study was designed to determine if the performance of this approach differs between Black and White women.
The researchers used data from the Surveillance, Epidemiology, and End Results (SEER) national cancer registry (2012-2016), the US census, and published estimates of ET distribution and fibroid prevalence for this study. The team constructed a simulated cohort of women, aged 45 years and older, who were experiencing postmenopausal bleeding.
The cohort consisted of 367,073 patients, including 44,611 Black women, 322,462 White women, and 36,708 women with endometrial cancer.
The primary endpoint was accuracy of the TVUS ET threshold to identify endometrial cancer, as determined by sensitivity, negative predictive value (NPV), and area under the curve (AUC).
There was a substantial disparity in prompted biopsies between Black and White women using the currently recommended ET threshold of 4 mm or greater.
Among Black women, the recommended threshold resulted in a biopsy in less than half of endometrial cancer cases. The sensitivity was 47.5%, the specificity was 64.9%, the positive predictive value (PPV) was 13.1%, and the NPV was 91.7% (AUC, 0.57; 95% CI, 0.56-0.57).
Among White women, the 4-mm or greater threshold resulted in a biopsy for most endometrial cancer cases. The sensitivity was 87.9%, the specificity was 42.7%, the PPV was 14.6%, and the NPV was 97.0% (AUC, 0.73; 95% CI, 0.73-0.74).
Similar disparities were present when ET thresholds of at least 3 mm or at least 5 mm were used.
“The findings of this simulated cohort study suggest that use of ET as measured by TVUS to determine the need for EC [endometrial cancer] diagnostic testing in symptomatic women may exacerbate racial disparities in EC stage at diagnosis,” the study authors wrote.
They added that TVUS ET screening missed more cases among Black women due to the greater prevalence of fibroids and nonendometrioid histologic type in Black women.
Disclosure: One study author declared affiliations with a pharmaceutical company and foundations. Please see the original reference for a full list of disclosures.
Doll KM, Romano SS, Marsh EE, Robinson WR. Estimated performance of transvaginal ultrasonography for evaluation of postmenopausal bleeding in a simulated cohort of Black and White women in the US. JAMA Oncol. Published online July 15, 2021. doi:10.1001/jamaoncol.2021.1700