Apparent diffusion coefficient on magnetic resonance imaging (MRI) in bladder cancer: relations with recurrence/progression risk

Abstract

AIMS :To evaluate the relationship between the apparent diffusion coefficient (ADC) value for bladder cancer and the recurrence/progression risk of post -transurethral resection (TUR). METHODS : Forty -one patients with initial and non -muscle -invasive bladder cancer underwent MRI from 2009 to 2012. Two radiologists measured ADC values. A pathologist calculated the recurrence/progression scores, and risk was classified based on the scores. Pearson's correlation was used to analyze the correlations of ADC value with each score and with each risk group, and the optimal cut -off value was established based on receiver operating characteristic (ROC) curve analysis. Furthermore, the relationship between actual recurrence / progression of cases and ADC values was examined by Unpaird U test. RESULTS : There were significant correlations between ADC value and the recurrence score as well as the progression score (P<0.01, P<0.01, respectively). There were also significant correlations between ADC value and the recurrence risk group as well as progression risk group (P=0.042, P<0.01, respectively). The ADC cut -off value on ROC analysis was 1.365 (sensitivity 100% ; specificity 97.4%) for the low and intermediate recurrence risk groups, 1.024 (sensitivity 47.4% ; specificity 100%) for the intermediate and high recurrence risk groups, 1.252 (sensitivity 83.3% ; specificity 81.3%) for the low and intermediate progression risk groups, and 0.955 (sensitivity 87.5% ; specificity 63.2%) between the intermediate and high progression risk groups. The difference between the ADC values of the recurrence and nonrecurrence group in Unpaired t test was significant (P<0.05). CONCLUSION : ADC on MRI in bladder cancer could potentially be useful, non -invasive measurement for estimating the risks of recurrence and progression.

VI‐RADS for Bladder Cancer: Current Applications and Future Developments

“…The VI‐RADS score might become a tool for prediction of both tumor aggressiveness and response to therapy, as well as a clinical predictor for perioperative outcomes. Several studies have demonstrated how MRI functional sequences are reliable in determining and predicting tumor aggressiveness 46,87–91 . Notably, ADC value quantification has been proposed as a potential biomarker by Kobayashi et al, showing that an ADC cutoff value of 0.86 × 10 –3 mm 2 /s (sensitivity of 88%, a specificity of 85%, and an accuracy of 87%) could be used to identify clinically aggressive phenotypes differentiating high grade tumors from less aggressive phenotypes 92 .…”

“…Several studies have demonstrated how MRI functional sequences are reliable in determining and predicting tumor aggressiveness. 46,[87][88][89][90][91] Notably, ADC value quantification has been proposed as a potential biomarker by Kobayashi et al, showing that an ADC cutoff value of 0.86 × 10 -3 mm 2 /s (sensitivity of 88%, a specificity of 85%, and an accuracy of 87%) could be used to identify clinically aggressive phenotypes differentiating high grade tumors from less aggressive phenotypes. 92 A few years before Takeuchi et al proposed the ADC value as a predictor of BCa grading, there were significant differences between the values of G1 and G3 and between G2 and G3.…”

A glance at imaging bladder cancer

“…The combination of ADC and wash-out rate determined the BCa aggressiveness with 96.7% sensitivity, 94.9% specificity, and 95.7% accuracy [43]. Also, ADC was useful for determining the recurrence and progression risk of BCa [19, 40, 44–46]. DWI-MRI however, helps distinguish benign and malignant bladder lesions, for staging, and for the assessment of efficacy of chemo-radiotherapy treatment [36].…”