Amide proton transfer imaging in differentiation of type II and type I endometrial carcinoma: a pilot study

PURPOSE: This study aimed at evaluating the efficacy of amide proton transfer (APT) imaging in differentiation of type II and type I uterine endometrial carcinoma. MATERIALS AND METHODS: Thirty-three patients diagnosed with uterine endometrial carcinoma, including 24 with type I and 9 with type II carcinomas, underwent APT imaging. Two readers evaluated the magnetization transfer ratio at 3.5 ppm [MTR(asym) (3.5 ppm)] in each type of carcinoma. The average MTR(asym) (APT(mean)) and the maximum MTR(asym) (APT(max)) were analyzed. The receiver operating characteristic (ROC) curve analysis was performed. RESULTS: The APT(max) was significantly higher in type II carcinomas than in type I carcinomas (reader1, p = 0.004; reader 2, p = 0.014; respectively). However, APT(mean) showed no significant difference between type I and II carcinomas. Based on the results reported by reader 1, the area under the curve (AUC) pertaining to the APT(max) for distinguishing type I from type II carcinomas was 0.826, with a cut-off, sensitivity, and specificity of 9.90%, 66.7%, and 91.3%, respectively. Moreover, based on the results reported by reader 2, the AUC was 0.750, with a cut-off, sensitivity, and specificity of 9.80%, 62.5%, and 87.5%, respectively. CONCLUSION: APT imaging has the potential to determine the type of endometrial cancer.