A Comparative Study of Calcified Epithelioma of Malherbe And Epidermoid Cyst With Ultrasound

Objective: To explore the ultrasonic(US)features of calcified epithelioma Malherbe (CEM) and epidermoid cyst(EC) in differential diagnosis and improve the accuracy of US diagnosis of CEM.Materials and Methods: We retrospectively analyzed 309 subjects, who underwent US examination before operation and pathological diagnosis for CEM or EC post-operation. The subjects were categorized into the training and validation sets according to different inspection times. The US and clinical features of CEM were evaluated through univariate analysis. A multivariate logistic regression model was used to establish the diagnostic model. Results: Statistically significant variables in univariate analysis(P<0.05)were included in the multivariate logistic regression model. The results demonstrated that the diagnostic model for CEM was statistically significant (P<0.001). The risk factors included posterior echo attenuation and hypoechoic halos (OR=9.277, 10.254) and the protective factors included age, thickness diameter, and posterior echo enhancement (OR=0.936, 0.302, 0.156). The diagnostic models tested in the training set (AUC=0.974, 95% CI=0.955-0.994) and the validation set(AUC=0.967, 95% CI=0.926-1.000) demonstrated good discriminant ability.Conclusions: The diagnostic accuracy for CEM is higher compared to EC when the nodule is characterized by posterior echo attenuation, hypoechoic halos, smaller thickness, and younger age. US diagnostic model can guide the diagnosis of CEM.