Application Value Of 3.0T Magnetic Resonance Imaging In Preoperative Staging And Grading Of Urinary Bladder Cancer

Part Ⅰ. Application value of different MR sequencescombination in preoperative staging of urinary bladder cancerObjective:To evaluate the application value of different magnetic resonance imaging (MRI) sequences combination in preoperative staging diagnosis of urinary bladder cancer.Methods:Different MRI sequences (T1WI, T2WI, DWI and DCE-MRI) were performed in 68 patients with bladder carcinoma. The images were analyzed by two radiologists and decisions were reached by consensus. To make differential diagnosis of the tumor staging, the sequences were divided into four kinds of combination: T2WI+T1WI(combination 1), T2WI+DWI(combination 2), T2WI+DCE-MRI (combination 3) and T2WI+DWI+DCE-MRI (combination 4). Calculate the sensitivity, specificity and accuracy for each combination, and apply Ttest method for comparison.Results:For the differential diagnosis of non-muscle invasive(NMIBC) and muscle invasive bladder cancer(MIBC), the area under the ROC curve of four combination in descending order:combined combination of 4 (0.970), combination of 2 (0.941), combination of 3 (0.895), combination 1 (0.816); combination 2, 4 and 1 have significant difference (p<0.05);combination of 3 and 4 have significant difference (p< 0.05).Sensitivity as follows:combination 2 to 4 (93.6%), combination 1 (80.7%); combination 2-4 and 1 have significant difference (p< 0.05).Specificity as follows:combination 4 (97.3%), combination 2 (94.0%), combination 3 (86.5%), combination 1 (75.7%); combination 2-4 and 1 have significant difference (p< 0.05) combination of 3 and 4 have significant difference (p< 0.05).Accuracy as follows:combination 4 (95.6%), combination 2 (93.7%), combination 3 (89.7%), combination 1 (77.9%); combination 2-4 and 1 have significant difference (p<0.05) combination of 3 and 4 have significant difference (p< 0.05). Four serial combination MRI in differentiating the differential diagnosis of bladder cancer Tis-T2 and T3-T4 staging,AUC as follows:combination 4 (0.946), combination 2 (0.910), combination 3 (0.843), combination 1 (0.745); combination 2,4 and 1 have significant difference (p= 0.025).Sensitivity as follows:combination 4 (88.2%), combination 2 (85.2%), combination 3 (76.5%), combination 1 (58.6%); combination 2,4 and 1 have significant difference (p=0.025). Specificity as follows:combination 4 (96.1%), combination 3 (90.2%), combination 2 (88.3%), combination 1 (82.4%); combination4 and 1 have significant difference (p=0.046).Accuracy as follows:combination 4 (94.1%), combination 3 (88.2%), combination 2 (87.2%), combination 1 (80.2%); combination4 and 1 have significant difference (p= 0.046).Conclusions:Combined use of MR sequences can improve the accuracy of urinary bladder cancer staging, while T2WI+DWI is expected to become the common combination in daily work, especially for NMIBC staging.Part Ⅱ. Application value of apparent diffusion coefficient in preoperative grading of urinary bladder cancerObjective:To analyze the application value of apparent diffusion coefficient in preoperative grading diagnosis of urinary bladder cancer.Methods:A total of 40 patients with bladder masses, undergone TIWI, T2WI and DWI scans (b=1200,1500 s/mm2). The images were analyzed by two radiologists and decisions were reached by consensus. To make differential diagnosis of the lesions, and to diagnose the grading of bladder cancers, The ADC values were measured and compared with pathological results.Results:Among 40 cases of patients, benign lesions was 32.5%(13/40), urothelial carcinoma was 67.5%(27/40), the low grade bladder cancer was 59.3%(16/27), high grade bladder cancer was 40.7%(11/27).Detection rate of DWI was 92.7%, higher than T2WI (83.6%) and T1WI (72.7%).b= 1200 s/mm2,the ADC values of benign and malignant lesions was (1.30±0.10)×10-3mm2/s and (0.84±0.08)×10-3mm2/s;b=1500 s/mm2, the average ADC values of benign and malignant lesions was (1.23±0.07) ×10-3mm2/s, (0.79±0.06)×10-3 mm2/s respectively; the ADC values between this two group have significant difference (p< 0.05).b= 1200 s/mm2, the ADC values of high and low grade urothelial carcinoma was (0.73±0.05) ×10-3 mm2/s, (0.90±0.02)×10-3 mm2/s respectively; b=1500 s/mm2,the ADC values of high and low grade urothelial carcinoma was (0.67±0.01)×10-3 mm2/s, (0.84±0.07) ×10-3 mm2/s respectively; the ADC values between two group have significant difference (p<0.05).Conclusion:ADC values are useful in the differential diagnosis of urinary bladder disease, the ADC values can play a crucial role in preoperative grading diagnosis of bladder cancer.