Mutations in both the MAPK/ERK pathway (e.g. BRAF, KRAS, NRAS, ERBB2, and ERBB3) and the PI3K/AKT/mTOR pathway (e.g. PIK3CA, IGF2, PTEN, and PIK3R1) are frequent in rectal cancer [1]. The gene discussed is PIK3CA; the disease is rectal cancer.