EGFR and dermatological toxicity: At univariate analysis for PFS, besides skin toxicity, another three variables were associated with an improvement in PFS: number of metastatic sites ≤2 (HR, 0.54; CI 95%, 0.33–0.87; p = 0.013); surgery of primary tumor (HR, 0.58; CI 95%, 0.36–0.94; p = 0.028); and RAS/BRAF/EGFR WT ctDNA status at baseline liquid biopsy analysis (HR, 0,41; CI 95%, 0.23–0.75; p = 0.004).