Overcoming cancer resistance in pancreatic cancer: toward dynamic precision oncology

Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal malignancy, largely because of its profound and evolving therapeutic resistance. Resistance is not determined by a single molecular alteration but arises from interconnected mechanisms, including intrinsic resistance, treatment-induced adaptive resistance, acquired resistance, genomic evolution, clonal selection, cancer stemness, phenotypic plasticity, metabolic adaptation, and tumor microenvironment-mediated effects. Emerging therapeutic approaches targeting KRAS/RAS signaling, stromal and immune components, metabolic dependencies, and DNA damage repair pathways offer opportunities to address these mechanisms, although durable efficacy remains limited by biological heterogeneity and adaptive responses. In this review, we examine therapeutic resistance as an evolutionary and multidimensional process and summarize emerging strategies for overcoming resistance. We further propose a Dynamic Precision Oncology (DPO) framework that extends conventional precision oncology beyond baseline molecular profiling by integrating longitudinal assessment of tumor genomics, circulating tumor DNA, CA19-9, imaging, radiomics, and clinical characteristics. This framework emphasizes iterative detection and characterization of emerging resistance, mechanism-informed treatment adaptation, and subsequent reassessment rather than automatic treatment modification based on a single biomarker. DPO may provide a conceptual framework for integrating evolving tumor biology into treatment decision-making, while prospective studies are needed to validate biomarkers, define actionable thresholds, and determine whether longitudinal resistance-guided strategies improve clinical outcomes in PDAC.