Texture analysis of CT colonography to develop a novel imaging biomarker for the management of colorectal cancer

Background: Recent studies have focused on evaluating the biomarker value of textural features in radiological images. Our study investigated whether or not a texture analysis of computed tomographic colonography (CTC) images could be a novel biomarker for colorectal cancer (CRC).

Methods: This retrospective study investigated 263 patients with CRC who underwent contrast-enhanced CTC (CE-CTC) before curative surgery between January 2014 and December 2017. Multiple texture analyses (fractal, histogram, and gray-level co-occurrence matrix [GLCM] texture analyses) were applied to CE-CTC (portal-venous phase), and fractal dimension (FD), skewness, kurtosis, entropy, and GLCM texture parameters, including GLCM-correlation, GLCM-autocorrelation, GLCM-entropy, and GLCM-homogeneity, of the tumor were calculated. These texture parameters were compared with pathological factors (tumor depth, lymph node metastasis, vascular invasion, and lymphatic invasion) and overall survival (OS).

Results: Tumor depth was significantly associated with FD, kurtosis, entropy, GLCM-correlation, GLCM-autocorrelation, GLCM-entropy, and GLCM-homogeneity (p = 0.001, 0.001, 0.001, 0.001, 0.018, 0.008, and 0.001, respectively); lymph node metastasis was associated with GLCM-homogeneity (p = 0.004); lymphatic invasion was associated with GLCM-correlation and GLCM-homogeneity (p = 0.001 and 0.012, respectively); and venous invasion was associated with FD, entropy, GLCM-correlation, GLCM-autocorrelation, and GLCM-entropy of the tumor (p = 0.001, 0.033, 0.021, 0.046, respectively). In the Kaplan-Meier analysis, patients with high GLCM-correlation tumors or high GLCM-homogeneity tumors showed a significantly worse OS than others (p = 0.001 and 0.04, respectively). Multivariate analyses showed that the GLCM correlation was an independent prognostic factor for the OS (p = 0.021).

Conclusion: CE-CTC-derived texture parameters may be clinically useful biomarkers for managing CRC patients.