Tumor histological studies showed that approximately 25.8% of colorectal primary tumors express an undetectable level of ARID1A and that another 50% of colorectal primary tumors express low levels of ARID1A (75.8% of colorectal tumors express a low or undetectable level of ARID1A)90. This evidence concerns the gene ARID1A and colorectal neoplasm.