A population-based study of the relationship between endometrial thickness and prevalence of breast mass in postmenopausal women.

Objectives: To determine the relationship between endometrial thickness and the prevalence of breast mass in postmenopausal women.

Methods: The prevalence of breast mass was investigated in 6759 postmenopausal women (≥60 years) with different endometrial thicknesses who underwent breast and transvaginal ultrasonography from January 2015 to June 2017. Multivariable logistic regression analysis was used to obtain odds ratios and 95% confidence intervals for breast mass in postmenopausal women with increased endometrial thickness after adjusting for age, height, and body mass index.

Results: Compared with a baseline endometrial thickness of less than 3 mm, the prevalence of breast mass increased in patients with endometrial thickness ≥3-4.9 mm (OR 1.077; 95% CI, 0.868-1.338), ≥5-9.9 mm (OR 1.910; 95% CI, 1.189-3.067), and ≥10 mm (OR 3.546; 95% CI, 1.458-8.620) (P =0.0026). In subgroup analysis, correlations between endometrial thickness and prevalence of breast mass with malignant possibility (BI-RADS ≥3) were similar and remained significant (P =0.035).

Conclusion: Postmenopausal women with endometrial thickness greater than or equal to 5 mm have a significantly increased prevalence of breast mass and breast mass with malignant possibility (BI-RADS ≥3). Breast cancer screening for postmenopausal women with increased endometrial thickness should be given greater attention.