The role of diffusion-weighted MR imaging in diagnosis of bladder cancer
10.3781/j.issn.1000-7431.2012.12.013
- Author:
Lian-Hua ZHANG
1
Author Information
1. Department of Urology
- Publication Type:Journal Article
- Keywords:
Apparent diffusion coefficient;
Diagnostic imging;
Magnetic resonance imaging;
Urinary bladder neoplsams
- From:
Tumor
2012;32(12):1025-1029
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To evaluate the value of DWI (diffusion-weighted imaging) of MR (magnetic resonance) and ADC (apparent diffusion coefficient) in diagnosis, staging and grading of bladder cancer. Methods: The DWI images of 73 patients with bladder masses were collected and the diagnostic sensitivity, specificity and accuracy of bladder cancer were evaluated. The ADC values of bladder cancer, the surrounding structures, the urine and the bladder inflammation were measured. The staging based on the DWI of bladder cancer was compared with pathology. The ADC values of different grades of urothelial carcinoma were determined and compared. Results: The diagnostic sensitivity, specificity and accuracy of bladder cancer by DWI were 92.3%, 75.0% and 90.4%, respectively. The mean ADC values of bladder cancer, the bladder inflammation, the surrounding structures and the urine were (0.97±0.25)×10-3, (1.49±0.15)×10-3, (1.47±0.13)×10 -3 and (2.57±0.17)×10-3 mm2/s, respectively. There were significant differences between bladder cancer and the surrounding structures, urine, and bladder inflammation. The sensitivity, specificity and accuracy to distinguish Tis-T1 and T 2-T4 bladder cancer by DWI were 93.2%, 68.8% and 86.7%, respectively, which were 77.3%, 50.0% and 70.0% by conventional MRI sequences, respectively. There was a difference between DWI and conventional MRI sequences (P = 0.027). The mean ADC values of high- and low-grade urothelial carcinoma were (0.78±0.13)×10-3 and (1.14±0.21) ×10-3 mm2/s. There was a significant difference between high- and low-grade urothelial carcinoma (P < 0.01). By using the ROC (receiver operating characteristic) curve, given the ADC value of 1.04×10-3 mm2/s considered as a threshold for distinguishing high- and low-grade urothelial carcinoma, the sensitivity and specificity were 84.8% and 91.7%, respectively. Conclusion: DWI and ADC value are helpful in diagnosis, staging and grading of bladder cancer. Copyright © 2012 by TUMOR.
