intravoxel incoherent motion MRI for prediction of histological grade and muscle invasion in bladder urothelial carcinoma / 中国医学影像技术

ABSTRACT

Objective To observe the utility value of MR intravoxel incoherent motion (IVIM) in histological grading and muscle invasion of bladder urothelial carcinoma.Methods According to postoperative histologic grade and T staging,60 patients with bladder urothelial carcinoma confirmed by surgery and pathology were divided into low grade (LG) group and high grade (HG) group,as well as muscle-noninvasive bladder cancer (NMIBC) or muscle-invasive bladder cancer (MIBC) group.MR IVIM parameters (apparent diffusion coefficient standard [ADCst],true diffusion coefficient [D],pseudodiffusion coefficient [D*] and perfusion fraction [f]) were compared with independent-samples t tests.A binary Logistic regression model was established to evaluate the predicted probability of combined IVIM parameters.ROC curves of IVIM parameters and their combination's predicted probability were drawn,and the diagnostic efficiency was evaluated.Results ADCst,D and f values of HG group were significantly lower than those of LG group (all P＜0.05).Area under ROC curve (AUCs) for ADCst,D and f value to differentiate HG from LG were 0.88,0.86 and 0.72,respectively (all P＜0.01),and AUCs for predicted probability of combined ADCst and D,combined ADCst and f and combined D and f were 0.91,0.90 and 0.88,respectively (all P＜0.0001).ADCst,D and f values of M1BC group were significantly lower than those of NMIBC group (all P＜0.0001).AUCs for ADCst,D and f value to differentiate MIBC from NMIBC were 0.91,0.85 and 0.88,respectively (all P＜0.0001),and all AUCs for predicted probability of combined ADCst and D,combined ADCst and f and combined D and f were both 0.93 (all P＜0.000 1).Conclusion Lower ADCst,D and f values may indicate greater possibility of high grade and muscle invasion of bladder urothelial carcinoma.Combination of IVIM parameters can improve diagnostic efficacy.