Accuracy of MR imaging for the prediction of myometrial invasion of endometrial carcinoma

Objectives.To retrospectively evaluate the accuracy of magnetic resonance (MR) imaging for the prediction of depth of myometrial invasion in the preoperative assessment of women with endometrial carcinoma.Methods.We retrospectively reviewed the medical records and MR imaging reports of 120 women with pathologically-proven endometrial carcinoma who underwent preoperative pelvic MR imaging between June 1997 and February 2006. Tumor signal intensity, the appearance of the junctional zone (JZ), the presence of large polypoid tumors and leiomyomas were analyzed. Univariate logistic-regression analysis was performed to identify associations between incorrect MR staging and the study variables.Results.Data from 120 patients were registered for the current study and analyzed. The sensitivity, specificity and accuracy of the MR imaging in assessment of myometrial invasion among patients with endometrial carcinoma were: 50.6%, 89.2% and 62.5% respectively. MR differentiation of deep myometrial invasion from superficial disease had an 83.3% accuracy (100 of 120 cases). Isointense JZ to myometrium (P < 0.001), and the presence of polypoid tumors (P = 0.037) on MR imaging were significantly associated with an underestimation of myometrial invasion by endometrial carcinoma.Conclusions.Isointense JZ to myometrium and polypoid tumors are difficult to accurately evaluate for myometrial invasion of endometrial carcinoma by MR imaging.