Uterine extension determined by MRI: a useful parameter for differentiating subserosal leiomyomas from ovarian tumors.

Abstract

This study aimed to evaluate the utility of uterine extension determined via MRI for the differentiation of large subserosal leiomyomas from ovarian tumors. In total, 55 patients with subserosal leiomyomas and 127 patients with ovarian tumors were included in this study. These patients were selected from a cohort of female patients whose pelvic masses were larger than 10cm and who underwent preoperative MRI. We retrospectively reviewed the MRI and compared the diagnostic ability of uterine extension measurements and bridging vascular signs for differentiating subserosal leiomyomas from ovarian tumors. The vertical height of the uterus (107.2 ± 36.4mm vs. 59.9 ± 24.9mm, p < 0.01), the uterine length (114.4 ± 34.9mm vs. 80.4 ± 23.8mm, p < 0.01), and the frequency of the bridging vascular sign (78% vs. 6%, p < 0.01) were significantly higher in subserosal leiomyomas than in ovarian tumors. For diagnosing subserosal leiomyoma, the area under the curve, sensitivity, and specificity of vertical height of the uterus, using cutoff threshold > 81mm, were 0.89, 89%, and 80% and those of the uterine length, using cutoff threshold > 84mm, were 0.85, 69%, and 93%, respectively. Alternatively, the sensitivity and specificity of bridging vascular sign were 78% and 94%, respectively. Uterine extension determined via MRI is a useful parameter for differentiating large subserosal leiomyomas from ovarian tumors.