CEACAM5 and neoplasm: However, we noted that both ESMO (including lymph nodes sampling <12; poorly differentiated tumor; vascular or lymphatic or perineural invasion; tumor presentation with obstruction or tumor perforation and pT4 stage) and ASCO (including patients with inadequately sampled nodes, T4 lesions, perforation, or poorly differentiated histology) did not regard elevated serum CEA levels as one of high-risk factors of stage II colon cancer (6, 7).