BRAF and colorectal carcinoma: Two large studies of 77 and 126 patients respectively, suggest that the risk of CRC in HPS is approximately 30–40% [28], [58], and coupled with a high background of somatic BRAF mutation (30–40% of CRC arising in HPS have a somatic BRAF mutation) [59], such an elevated risk may simply serve to overwhelm any effect of smoking on BRAF-mutated CRC.