Myometrial invasion and overall staging of endometrial carcinoma: assessment using fusion of T2-weighted magnetic resonance imaging and diffusion-weighted magnetic resonance imaging.

BACKGROUND: The age of onset of endometrial carcinoma has been decreasing in recent years. In endometrial carcinoma, it is important to accurately assess invasion depth and preoperative staging. Fusion of T2-weighted magnetic resonance imaging (T2WI) and diffusion-weighted magnetic resonance imaging (DWI) may contribute to the improvement of anatomical localization of lesions.

MATERIALS AND METHODS: In our study, a total of 58 endometrial carcinoma cases were included. Based on the revised 2009 International Federation of Gynecology and Obstetrics staging system, a fusion of T2WI and DWI was utilized for the evaluation of invasion depth and determination of the overall stage. Postoperative pathologic assessment was considered as the reference standard. The consistency of T2WI image staging and pathologic staging, and the consistency of fused T2WI and DWI and pathologic staging were all analyzed using Kappa statistics.

RESULTS: Compared with the T2WI group, a significantly higher diagnostic accuracy was observed for myometrial invasion with fusion of T2WI and DWI (77.6% for T2WI; 94.8% for T2WI-DWI). For the identification of deep invasion, we calculated values for diagnostic sensitivity (69.2% for T2WI; 92.3% for T2WI-DWI), specificity (80% for T2WI; 95.6% for T2WI-DWI), positive predictive value (50% for T2WI; 85.7% for T2WI-DWI), and negative predictive value (90% for T2WI; 97.7% for T2WI-DWI). In summary, T2WI-DWI fusion exhibits higher diagnostic accuracy with respect to staging relative to T2WI only (81.0% for T2WI; 94.8% for T2WI-DWI).

CONCLUSION: Fused T2WI-DWI may represent a noninvasive, lower cost approach for the effective assessment of myometrial invasion and staging of endometrial carcinoma.