Abstract

Epidermal growth factor receptor (EGFR) is a key driver in the pathogenesis of nonsmall cell lung cancer (NSCLC) and colorectal cancer (CRC), making it a central target in precision oncology. This review examines the clinical utility of EGFR-targeted therapies, including tyrosine kinase inhibitors (TKIs) and monoclonal antibodies (mAbs), while addressing the mechanisms of therapeutic resistance that limit long-term efficacy. Emphasis is placed on the diagnostic landscape, from traditional PCR-based assays and tissue biopsies to advanced tools such as liquid biopsy, droplet digital PCR (ddPCR), and nextgeneration sequencing (NGS). The review also explores emerging platforms, including nanotechnology and CRISPR-based diagnostics, for their potential to enhance mutation detection accuracy and real-time monitoring. By evaluating current limitations, detection gaps, and integration challenges, this paper underscores the urgent need for multi-modal, high-sensitivity approaches to improve clinical decision-making and optimize outcomes in EGFR-driven malignancies.

Keywords

colorectal cancer, tyrosine kinase inhibitors, liquid biopsy, T790M, mutation detection, personalized therapy, next-generation sequencing, drug resistance, immunohistochemistry, CRISPR diagnostics