Value of diffusion weighted magnetic resonance imaging in grading of urinary bladder carcinoma

Aim of the study: to evaluate the role of diffusion weighted magnetic resonance imaging in urinary bladder cancer grading in comparison to histopathological grading. Patients and methods: This prospective study included 50 patients; 30 males and 20 females with mean age 66.4 years. All patients were referred clinically for bladder cancer and hence all of them underwent MR imaging. T2 weighted images were acquired followed by diffusion study in the same plane, b value = 800 s/mm(2). Results: pathologic staging was between Tis and T1 (superficial) in 28% of tumors. More than T1 (Deep) in 72%. The mean ADC value was 1.203 x 10(-3) with a standard deviation of +/- 0.385 x 10(-3). The mean ADC value for stages Tis to T1 tumors was 1.505 x 10(-3) +/- 0.270 SD; and stages T2 to T4 tumors was 1.085 +/- 0.385 SD; P < 0.001. Cutoff ADC value was 1.275 x 10(-3) as a useful indicator for differentiating stages Tis to T1 from T2 to T4; P < 0.005. Conclusion: DW imaging is a noninvasive reliable modality for predicting histopathological aggressiveness of bladder cancer.