For gastrointestinal cancer patients, 8 tier-1 genes, namely APC, CASP8, GRIN2A, MYH9, TP53, ASXL1, CDH11, and KRAS, were consistently identified by both ctDNA WES and tumor WES as the most frequently mutated genes (Fig 4B). This evidence concerns the gene ASXL1 and neoplasm.