To identify the critical genes which could effectively delineate this distinct set of HST/HSN, among the 42 CRC reference genes, 8 reference genes (CLTC, SDC1, FAM120A, ARPC5, HEBP2, RAB1A, RAB1B, ACTR2) with relatively greater CV values among HST were selected (Additional file 1: Figure S3a). This evidence concerns the gene SDC1 and colorectal carcinoma.