PIK3CA and colorectal carcinoma: In CRC, the mutation rate of MAPK pathway genes was 16.7% in group 1, 25.0% in group 2, and 76.5% in group 3, whereas that of PI3K/MTOR pathway genes was 33.3% in group 1, 62.5% in group 2, and 70.6% in group 3.