Adjunctive use of the uterine artery resistance index in the preoperative prediction of myometrial invasion in endometrial carcinoma

Abstract

Objective. The aim of this study was to evaluate the value of transvaginal ultrasonography (TVUS) and uterine artery flow velocimetry indices in the preoperative detection of deep myometrial invasion in endometrial carcinoma (EC). Methods. Thirty-nine patients with EC underwent TVUS and Doppler flow velocimetry studies, during which endometrial, myometrial, and uterine measurements, presence and depth of myometrial invasion, and pulsatility and resistance indices (PI and RI, respectively) of uterine arteries were noted. TVUS and Doppler findings were correlated with pathological findings obtained by surgical staging. The respective diagnostic accuracies of these variables, and of age and grade, in detecting deep myometrial invasion were assessed with the use of histological findings as the standard. Results. All patients with Grade 3 tumors had deep myometrial invasion, compared to 19% of patients with Grade 1 tumors. The mean age of patients with deep invasion was significantly higher, and their mean PI and RI were significantly lower, than patients with lesser degrees of invasion. While the sensitivity and specificity of TVUS in detecting deep invasion were 37 and 90%, respectively, the corresponding figures for age, grade, and uterine artery RI, found to be independent discriminators of deep invasion, were in the range of 58-84% and 60-70%. The combined use of the latter three parameters resulted in a sensitivity of 100% and specificity of 95%. Conclusions. Our findings indicate that TVUS is unreliable in diagnosing deep myometrial invasion. Detection rates of this pathological feature can be greatly improved, however, with the concomitant use of age, tumor grade, and uterine artery RI.