CEACAM5 and cholangiocarcinoma: As shown in Table 4, we found that preoperative cholangitis (p = 0.001, HR = 2.128, 95% CI (1.371–3.301)), elevated CEA level (p < 0.0001, HR = 2.313, 95% CI (1.488–3.594)), and nerve invasion (p = 0.038, HR = 1.596, 95% CI (1.027–2.481)) were risk factors for the OS of cholangiocarcinoma patients, while the high LMR level (p = 0.003, HR = 0.517, 95% CI (0.336–0.796)) and postoperative treatment (p = 0.009, HR = 0.582, 95% CI (0.387–0.875)) were protective factors for the OS of cholangiocarcinoma patients.