Preoperative transvaginal ultrasonography and intraoperative gross examination for assessing myometrial invasion by endometrial cancer

Objective. Endometrial cancer is the most common gynecologic malignancy. The cornerstone of treatment remains surgery according to International Federation of Gynecology and Obstetrics staging. The aim of this study was to evaluate the concordance between myometrial infiltration detected by ultrasonography and gross examination with respect to definitive histologic examination and to select a population in which lymphadenectomy could be excluded. We also evaluated the concordance for the degree of tumor differentiation between diagnostic biopsy and final histologic results. Methods. Our study included 75 patients with International Federation of Gynecology and Obstetrics stage I endometrial cancer. We evaluated preoperative and definitive grading and myometrial infiltration detected by ultrasonography and gross examination. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the procedures under study were determined with the Bayes theorem. To determine the predictive value of preoperative transvaginal ultrasonography and intraoperative gross examination for myometrial invasion, we used a multiple logistic regression model with a statistical software package. Results. Our study showed 60% concordance between biopsy and histologic results. In 80% of the cases with discordant results, the tumor was undergraded. Ultrasonography had diagnostic accuracy of 73%, whereas gross examination correctly determined myometrial invasion in 82.6% of the patients, with sensitivity of 62% and specificity of 79%. Conclusions. Preoperative transvaginal ultrasonography and macroscopic gross examination appear to be simple, fast, and reliable methods to predict in myometrial invasion in patients with a low risk for lymph node metastasis, for which lymphadenectomy can reasonably be avoided. Key words: endometrial cancer; histologic grading; intraoperative gross examination; myometrial invasion; preoperative transvaginal ultrasonography.