CEACAM5 and colorectal carcinoma: To further confirm these results, we divided 134 CRC patients after capecitabine treatment into two groups based on the level of CEA or CA199, and compared the expression level of CD16 on CD11b+CD16+myeloid cells between CEA-high (CEA > 5 ng) and CEA-low (CEA ≤ 5 ng) groups, or between CA199-high (CA199 > 27 ng) and CA199-low (CA199 ≤ 27 ng) groups.