CEACAM5 and neoplasm: Among patients with carcinoembryonic antigen levels above the threshold (Table 5), exon 19 deletion (P = 0.031), large tumour size (P = 0.001), IAC pathology (P = 0.012), confirmed lymphatic metastasis (P = 0.001), and advanced pathological stage (P = 0.029) were found by univariate analysis to be unfavourable for disease-free survival.