CEACAM5 and metastatic malignant neoplasm in the lymph nodes: As shown in Table 1, tissue hsa_circ_0001811 expression level was related to CEA (P = .0347), tissue differentiation (P = .0138), and lymph node metastasis (P = .0234), while plasma hsa_circ_0001811 level (Table 2) was related to CA19‐9 (P = .0278), lymph node metastasis (P = .0469) and distant metastasis (P = .0384), and age (P = .0085).