Immunohistochemistry (IHC) for VSIG1, MUC17, CTSE, TFF2 and REG4 in a panel of routinely formalin fixed and paraffin embedded SSA/Ps, hyperplastic polyps, adenomatous polyps, and control specimens was done to further validate the RNA-seq data, identify the cell types involved in overexpression and to investigate their potential diagnostic utility for differentiating SSA/Ps from other polyps. This evidence concerns the gene CTSE and hyperplastic polyp.