A New Hope: Dual Human Epidermal Growth Factor Receptor 2 Blockade and Chemotherapy in Human Epidermal Growth Factor Receptor 2-Amplified Colorectal Cancer - A Case Report and Literature Review.

Introduction: Monoclonal antibodies targeting epidermal growth factor receptors (EGFRs) are currently the preferred targeted therapeutic agents for RAS wild-type, left-sided metastatic colorectal cancer (mCRC). Nonetheless, certain molecular alterations within mCRC confer resistance to anti-EGFR monoclonal antibody therapy, notably alterations involving human epidermal growth factor receptor 2 (HER2). Colorectal cancer (CRC) characterized by HER2 amplification or overexpression may have markedly different prognoses than HER2-negative CRC does. Recent clinical trials have demonstrated that dual HER2 blockade leads to significant improvements in clinical outcomes for these patients. Case Presentation: In this study, we present a case in which HER2-positive mCRC was successfully treated with HER2-targeted agents combined with chemotherapy, resulting in favorable clinical outcomes. Conclusion: Dual HER2-targeted therapy combined with chemotherapy is a promising strategy for HER2-positive mCRC patients with good performance status. This approach warrants validation in large-scale clinical trials to confirm its efficacy.