Age-Related Multigene Analysis of Colorectal Cancer Using Next-Generation Sequencing

Colorectal cancer (CRC) remains a major global health problem, with rising incidence among younger individuals. The implementation of next-generation sequencing (NGS) has enabled comprehensive multigene analysis to identify cancer-predisposing variants and molecular alterations in tumors. However, data on age-related genetic differences in CRC from Central and Eastern European populations, including Poland, remain limited.

This study aimed to explore molecular differences in CRC between patients aged ≤50 and >50 years in a Polish cohort. Tumor DNA was extracted from formalin-fixed, paraffin-embedded (FFPE) tissue samples obtained from 54 treatment-naive patients. Targeted sequencing of hot spot regions of 50 genes with known association to cancer was performed using an AmpliSeq for Illumina Cancer Hotspot Panel v2.

Variant frequencies in younger vs. older patients were: TP53 (71.4% vs. 57.6%), APC (57.1% vs. 45.5%), KRAS (28.1% vs. 72.7%), NRAS (28.6% vs. 0%), SMAD4 (9.5% vs. 12.1%), PIK3CA (14.3% vs. 24.2%), and FBXW7 (4.8% vs. 14.7%). Co-occurrence of APC/KRAS/TP53 variants was observed in 20% of cases. KRAS mutations were significantly more frequent in older patients (p-value = 0.001), while NRAS mutations occurred exclusively in younger patients (29% vs. 0%, p = 0.021). Overall, 46% of patients exhibited multiple gene alterations (≥3 mutations). Notably, IDH1 and CTNNB1 variants were found only in patients with better prognosis, whereas TP53 variants were nearly five times more frequent in patients with worse outcomes.

Multigene panel sequencing revealed distinct age-related molecular patterns in CRC. Younger patients were more likely to harbor NRAS variants, whereas KRAS alterations predominated in older individuals. These findings underscore the relevance of NGS-based multigene profiling for risk stratification and personalized therapy in colorectal cancer.