Risk Stratification Prediction of Endometrial Cancer Using Microstructural Mapping Based on Time-Dependent Diffusion MRI

Time-dependent diffusion MRI (t-dMRI) has potential in characterizing microstructural features; however, its value in imaging endometrioid endometrial adenocarcinoma (EEA) remains uncertain. Patients surgically confirmed with EEA were finally enrolled in our study. The t-dMRI data were acquired using pulsed gradient spin echo sequence and oscillating gradient spin echo sequences. The microstructural markers, including cell diameter, intracellular volume fraction (V), cellularity, and extracellular diffusivity (D), were fitted with the imaging microstructural parameters using a limited spectrally edited diffusion (IMPULSED) model. The parameters were compared between low- and high-risk groups and between low- and high-proliferation groups. The diagnostic performance was evaluated using receiver-operating characteristic curve and logistic regression analysis. Diameter, D, ADC, ADC, and ADC were significantly low, whereas cellularity, ΔADC1 and ΔADC2 were significantly high in the high-risk and high-proliferation groups. Cellularity, ΔADC1, and ΔADC2 demonstrated excellent diagnostic efficacy in predicting both risk stratification and proliferation status. Cellularity was the only independent predictor for risk stratification, which exhibited a satisfactory positive correlation with cell density in histopathologic examination. The diagnostic potential of t-dMRI-based microstructural mapping was demonstrated to noninvasively probe the pathologic characteristics of patients with EEA in a clinical setting, which provided a valuable contribution to surgical guidance.