CEACAM5 and neoplasm: While Sm1 tumors have a LNM rate of 3.4%, the rate goes up to 22.6% if the lower third of the Sm is infiltrated (27), while CRC Sm1 tumors have a LNM rate of 3.4%, similar to our findings of tumor size <3 cm, well differentiated, negative CEA level, and adenocarcinoma in elderly patients with T1 colorectal cancer of LNM rate 4.6% (15 out of 325).