RESUMEN
We report the case of a patient with a BRAFV600E mutant mCRC, with evidence of acquired 'NeoBRAF wild-type' (wt) state. The patient, longitudinally assessed by liquid biopsy, obtained a remarkable clinical outcome with a multimodal approach including surgery, systemic treatment and targeted therapy. In patients with newly diagnosed RAS and BRAFV600E mutant mCRC, longitudinal assessment with liquid biopsy is not routinely used in clinical practice. We report the case of a patient with a BRAFV600E mutant mCRC, with evidence of acquired 'neoBRAF wild-type' (wt) state. The patient obtained a remarkable clinical outcome and has been longitudinally assessed by liquid biopsy.
RESUMEN
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 EntropyHistogram (p = 0.021), HomogeneityGLCM (p < 0.001) and Dissimilarity GLCM (p = 0.002). At multivariate analysis, only HomogeneityGLCM resulted significant for PFS (p = 0.001). Patients (19/39, 48.7%) with reduction of HomogeneityGLCM 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 HomogeneityGLCM. Overall survival was significantly better in this subgroup of patients with low HomogeneityGLCM: 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 HomogeneityGLCM 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.