Assoc. Prof. Huy Trinh Le (Hanoi Medical University, Vietnam) expanded the session to gastrointestinal malignancies, focusing on colorectal and gastric cancer. He emphasized the critical role of advanced biomarkers in stratifying patients, guiding treatment decisions, and predicting outcomes. In colorectal cancer, routine evaluation includes KRAS, NRAS, BRAF, PIK3CA, MSI/dMMR, TMB, and gene fusions. For gastric cancer, key markers include HER2, CLDN18.2, MSI/dMMR, and PD-L1.
Using two clinical cases, he illustrated how comprehensive genomic profiling (tissue + liquid) and circulating tumor DNA (ctDNA) analysis via the K-TRACK platform can be applied in practice. In the first case (stage III colon cancer at the splenic flexure), CGP detected KRAS and PIK3CA mutations along with dMMR status. Persistent ctDNA positivity after surgery and chemotherapy signaled a high-risk of recurrence despite standard care. In the second case (stage III cecal cancer), CGP identified a BRAF V600E mutation with pMMR, and ctDNA remained positive, indicating poor prognosis and supporting the continuation of maintenance therapy during follow-up. In both cases, dual liquid and tissue CGP enabled comprehensive molecular risk stratification and informed treatment planning, while ctDNA proved valuable for detecting minimal residual disease.
“From a prognostic perspective, Patients with positive ctDNA after curative treatment (stage II–III) have significantly worse survival outcomes. Thus, ctDNA is clearly useful for prognostic assessment,” he concluded. However, he noted that more evidence is still needed before ctDNA can routinely guide treatment changes. Looking ahead, Assoc. Prof. Huy highlighted the shift toward a multi-omics approach, which holds a significant potential by integrating genomic and transcriptomic insights with tumor microenvironment factors.
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