To investigate the survival and prognosis of distal cholangiocarcinoma (DCCA) and its prognostic factors.

Clinicopathological data of 116 DCCA patients who underwent pancreaticoduodenectomy from January 2011 to December 2019 were retrospectively analyzed. The informed consents of all patients were obtained and the local ethical committee approval was received. Among them, 71 patients were male and 45 female, aged from 31 to 82 years, with a median age of 65 years. The survival and prognosis were followed up. Survival analysis was performed by Kaplan-Meier method and Log-rank test. The influencing factors of survival and prognosis were analyzed by multivariate Cox’s regression analysis.

The 1-, 3- and 5-year overall survival rates of patients with DCCA after operation were 75.2%, 41.9% and 31.5%, respectively. Multivariate Cox’s regression analysis showed that the expression level of epidermal growth factor receptor (EGFR) (RR=1.600, 95%CI: 1.086-2.357), metastatic lymph node ratio (MLNR) (RR=2.899, 95%CI: 1.365-6.158) and degree of tumor differentiation (RR=2.009, 95%CI: 1.245-3.243) were the independent risk factors for long-term survival of DCCA patients after operation. The 1-,3- and 5-year survival rates of patients with MLNR=0 were 83.0%, 50.7% and 42.5%, and 80.5%, 37.4% and 37.4% for those with 0<MLNR≤0.17, and 48.2%, 0 and 0 for those with MLNR>0.17, respectively. The higher the MLNR, the worse the prognosis (χ²=26.834, P=0.006). The 1-, 3- and 5-year survival rates of EGFR-negative patients were 80.3%, 50.3% and 41.2%, and 81.3%, 16.2% and 16.2% for those with weak expression of positive EGFR, and 27.8%, 0 and 0 for those with moderate and high expression of positive EGFR, respectively. The higher the EGFR expression, the worse the overall survival (χ²=20.848, P=0.017). The 1-, 3- and 5-year survival rates of highly-differentiated DCCA patients were 92.9%, 68.8% and 68.8%, and 83.8%, 40.3% and 32.3% for those with moderately-differentiated DCCA, and 50.8%, 19.8% and 19.8% for those with poorly-differentiated DCCA, respectively. The lower the degree of tumor differentiation, the worse the prognosis (χ²=32.493, P=0.004).

Pancreaticoduodenectomy remains the optimal treatment for patients with DCCA. The expression levels of MLNR, EGFR and the degree of tumor differentiation are the independent risk factors of postoperative survival of DCCA patients. The higher the MLNR, the worse the prognosis. The higher the EGFR expression level, the worse the prognosis. The lower the degree of tumor differentiation, the worse the prognosis.