The value of diffusion weighted MR imaging in T staging and correlation with histologic grading in urinary bladder cancer

PurposeTo evaluate role of diffusion weighted MR imaging (DW MRI) in T staging of urinary bladder carcinoma and to measure correlation between ADC value and histopathological grade.Patients and methodsDuring the period between February 2012 and April 2014, 30 patients (28 males and 2 females) presenting with hematuria were enrolled prospectively. All patients underwent transurethral cystoscopy followed by standard MRI protocol and diffusion weighted MR imaging of urinary bladder tumors and histological examination of resected specimens.ResultsCorrelation between standard MR staging of bladder carcinoma and histopathological results revealed that 26 patients (86.7%) had the same T stage while 4 patients (13.3%) were overstaged. DWI and ADC values were able to declare the cause of overstating by discrimination between tumoral tissue and peritumoral inflammation. A statistically significant difference is found between ADC values of the bladder tumor and those of urine. Also a statistically significant difference is found between ADC values of G1 and G3 (p < 0.01) and between G2 and G3 (p < 0.01) but not between G1 and G2.ConclusionAccurate predictions for T staging of urinary bladder carcinoma can be made by means of DWI and ADC quantification. ADC value is a beneficial method for providing information about grade of bladder carcinomas.