Several studies have assessed HER2 overexpression in CRC, with some reporting membranous expression, varying in the range 2.1–11% in 9, 10, 11, 12, 13, 14, 15, and others reporting cytoplasmic overexpression in the range 47.4–68.5% 12, 16, 17. This evidence concerns the gene ERBB2 and colorectal carcinoma.