Treatment with anti–epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) in combination with chemotherapy is a standard of care as first-line treatment for patients with RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC).1 Despite an initial antitumor activity with high overall response rate (ORR), disease progression almost inevitably occurs as a result of cancer cells acquiring resistance.2,3. This evidence concerns the gene BRAF and metastatic colorectal cancer.