Two Transcriptomic Analyses Converge on a Five-Gene Core for Colorectal Cancer Discrimination: External Validation in Independent Tissue Cohorts

Background/Objectives: Colorectal cancer (CRC) is a leading cause of neoplasia-related morbidity and mortality worldwide and the first cause of cancer death in Mexico, where early detection remains a challenge, and reliable molecular biomarkers could support earlier diagnosis. Transcriptomic signatures for CRC have been published, but different studies arrive at gene lists that barely overlap, and since each study differs in both cohort and analysis, the source of that disagreement cannot be identified. This study aimed to identify a gene set for CRC discrimination whose selection depends neither on how the batch effect is handled nor on the criterion by which candidates are chosen and to validate that set in repositories that took no part in its selection.