Correlation between apparent diffusion coefficient values and histopathological grading of cerebral gliomas

Objective To investigate the relationship between apparent diffusion coefficient (ADC) values and histopathological grading of cerebral gliomas. Methods A retrospective analysis was performed to investigate the clinical data of 76 patients with cerebral gliomas, admitted to our hospital from April 2013 to December 2016. According to Classification Criteria of Central Nervous System Tumors by WHO in 2016, these 76 patients were divided into low grade cerebral glioma group (grading I-II, n=21), moderate grade cerebral glioma group (grading III, n=23) and high grade cerebral glioma group (grading IV, n=32). MR imaging, enhanced MR imaging and diffusion weighted imaging (3.0T, b value: 1000 s/mm2) were performed to detect the ADC values. One-way ANOVA was used to compare ADC values between the 3 different histopathological groups. Spearman correlation analysis was used to analyze the correlation between histopathological grading of cerebral gliomas and ADC values. A receiver operating characteristic curve (ROC) analysis was performed to evaluate the diagnostic efficiency of ADC values. Results The ADC values of low grade, moderate grade and high grade cerebral gliomas were (1.37±0.26)×10-3 mm2/s, (0.97±0.11)×10-3 mm2/s, (0.75±0.13)×10-3 mm2/s, respectively; statistically significant differences were observed between each two groups (P<0.05). There was a negative correlation between ADC values and histopathological grading of cerebral gliomas (r=-0.868, P=0.000). ROC analysis showed that the optimal cutoff point of ADC values was 1.11×10-3 mm2/s in diagnosing low grade cerebral gliomas, enjoying sensitivity and specificity of differential diagnosis of 95.2% and 96.4%; ROC curve showed that the optimal cutoff point of ADC values was 0.93×10-3 mm2/s in diagnosing high cerebral gliomas, enjoying sensitivity and specificity of differential diagnosis of 81.8% and 93.7%. Conclusion ADC values are important for predicting histopathological grading of cerebral gliomas. Key words: Cerebral glioma; Apparent diffusion coefficient; Magnetic resonance imaging; Diffusion magnetic resonance imaging; Pathology