Aim: To predict the myometrial invasion with three-dimensional (3D) ultrasonography in a cohort of patients with endometrial carcinoma by a previously described technique. Material and methods: The moyometrial infiltration was evaluated by 3D ultrasonography before surgery in 54 patients with endometrial carcinoma. After scanning the whole uterus by ultrasonography, three perpendicular planes were identified to find the shortest myometrial tumor-free distance to serosa (TDS) by examining the lateral, anterior, posterior, and fundal parts of the myometrium. Myometrial infiltration was also estimated by the subjective impression of the examiner. The reference standards consist of myometrial infiltration and TDS which are measured by an experi...