It has been reported that 82% of non-metastatic rectal cancers have mutations in cancer-driving genes belonging to the PI3K and MAPK pathways, including KRAS, PIK3CA, and TP53 [17], similar to colon cancer, but the distribution of these mutations was different between rectal and colon samples [14,16]. The gene discussed is PIK3CA; the disease is colonic neoplasm.