Radiomic Parameters for the Evaluation of Response to Treatment in Metastatic Colorectal Cancer Patients with Liver Metastasis: Findings from the CAVE-GOIM mCRC Phase 2 Trial

Background CAVE is a single arm, Phase 2 trial, that demonstrated anti-tumor activity of cetuximab rechallenge plus avelumab in patients with RAS wild type (wt) metastatic colorectal cancer (mCRC). Objective We conducted a post hoc analysis to identify potential radiomic biomarkers for patients with CRC liver metastasis (LM). Patients and Methods Patients with LM that could be measured by enhanced contrast phase computed tomography (CT) imaging at baseline and at first response evaluation were included. Multiple texture parameters were extracted with the LifeX Software. Delta-texture (D-TA) variations were calculated by comparing data at baseline and after treatment. Results Overall, 55/77 patients (71%) had LM; 39 met the inclusion criteria for the current analysis. The D-TA parameters that significantly correlated at univariate analysis with median progression-free survival (mPFS) were Entropy Histogram ( p = 0.021), Homogeneity GLCM ( p < 0.001) and Dissimilarity GLCM ( p = 0.002). At multivariate analysis, only Homogeneity GLCM resulted significant for PFS ( p = 0.001). Patients (19/39, 48.7%) with reduction of Homogeneity GLCM experienced better mPFS (4.6 vs 2.9 months; HR 0.45; 95% CI 0.23–0.88; p = 0.021) and median overall survival (mOS) (17.3 vs 6.8 months; HR 0.40, 95% CI 0.21–0.80; p = 0.010). A trend to better mPFS, was also observed in patients with RAS/BRAF wt circulating tumor DNA and reduction of Homogeneity GLCM . Overall survival was significantly better in this subgroup of patients with low Homogeneity GLCM : mOS was 17.8 (95% CI 15.5–20.2) versus 6.8 months (95% CI 3.6–10.0) (HR 0.34, 95% CI 0.14–0.81; p = 0.016). Conclusion Reduction in the D-TA parameter Homogeneity GLCM by radiomic analysis correlates with improved outcomes in patients with LM receiving cetuximab rechallenge plus avelumab therapy. Larger prospective studies are needed to validate and confirm these findings.