Assessing myometrial infiltration by endometrial cancer: uterine virtual navigation with three-dimensional US

Abstract

Purpose: To describe and analyze the diagnostic performance of uterine virtual navigation with three-dimensional (3D) ultrasonography (US) for the assessment of the depth of myometrial infiltration by endometrial cancer.

Materials and methods: Institutional review board approval was obtained; patients gave oral informed consent. Women with endometrial cancer were evaluated by using 3D US prior to surgical staging. A 3D volume of the whole uterus was obtained and analyzed by using software. Virtual navigation through three orthogonal planes was performed to identify the shortest myometrial tumor-free distance to serosa (TDS) by analyzing the lateral, anterior, posterior, and fundal portions of the myometrium. Myometrial infiltration was also assessed by subjective impression of an examiner. Histologic findings of myometrial infiltration and TDS measured by a pathologist were used as the reference standard. A receiver operating characteristic curve was plotted to identify the best cutoff for TDS for identifying myometrial infiltration of 50% or more.

Results: Ninety-six women (mean age, 61.8 years; range, 31-86 years) with endometrial cancer were included in the study. At histologic analysis, myometrial invasion was found to be less than 50% in 69 (72%) cases and 50% or more in 27 (28%) cases. TDS measured with US was positively correlated with histologically measured TDS (r = 0.649; 95% confidence interval: 0.52, 0.76). The best cutoff for US-measured TDS was 9.0 mm (sensitivity, 100%; specificity, 61%; negative predictive value, 100%; positive predictive value, 50%). Subjective impression had a sensitivity of 92.6%, a specificity of 82.3%, a negative predictive value of 96.6%, and a positive predictive value of 67.7%.

Conclusion: Uterine virtual navigation with 3D US is a reliable method for the assessment of myometrial infiltration in patients with endometrial cancer.