CEACAM5 and colorectal carcinoma: For stage I CRC, 92% (11/12) samples were PPP1R3C methylation(+), whereas only 17% (2/12) were CEA(+) (P = 3 × 10−4, Fisher's exact test) and 0% (0/12) was CA19-9(+) (P = 5 × 10−6).