With regard to specific gene mutations in non-hereditary (i.e., somatic) CRC, APC is mutated in 85%, TP53 in 40–50%, PIK3CA in 35% (activating mutations), and TGFBR2 in 45–50% of sporadic CRCs (Markowitz and Bertagnolli, 2009). The gene discussed is PIK3CA; the disease is colorectal carcinoma.