Abstract： Objectives:To construct a nomogram for the prediction of lymph node metastases of intrahepatic cholangiocarcinoma (ICC) based on inflammation-related markers,and to conduct its clinical verification.Methods:Clinical and pathological data from 858 ICC patients who underwent radical resection were retrospectively collected from 10 domestic tertiary hospitals in China from January 2010 to December 2018. Among the 508 patients who underwent lymph node dissection,207 cases had complete variable clinical data to construct the nomogram,including 84 males and 123 females,109 patients≥60 years,98 patients<60 years and 69 patients were pathologically diagnosed with positive lymph nodes after surgery. The receiver operating characteristic curve was drawn to calculate the accuracy of preoperative imaging examinations to determine the status of the lymph nodes,and the difference in overall survival time was compared by Log-rank test. Partial regression squares and statistically significant preoperative variables were screened by backward stepwise regression analysis. Software R was applied to construct a nomogram,clinical decision curve, clinical influence curve,and the Bootstrap method was used for internal verification. Additionally,retrospectively collecting clinical information from 107 ICC patients with intraoperative lymph node dissection admitted to 9 tertiary hospitals in China from January 2019 to June 2021 was for external verification to verify the accuracy of the nomogram. Eighty patients with complete clinical data but without lymph node dissection were divided into high-risk lymph node metastasis group and low-risk group according to the nomogram score among the 858 patients. Log-rank test was used to compare the overall survival of patients with or without lymph node metastasis diagnosed by pathology.Results:The area under the curve of preoperative imaging examinations for the assessment of lymph node status of 440 patients was 0.615,with a false negative rate of 62.8% (113/180) and a false positive rate of 14.2% (37/260). The median survival time of 207 patients used to construct a nomogram with positive or negative postoperative pathological lymph node metastases was 18.5 months and 27.1 months,respectively ( P<0.05). Five variables related to lymph node metastasis were screened by a stepwise backward regression analysis,which were combined calculi,neutrophil/lymphocyte ratio,albumin,invasion of the liver capsule and the systemic immune inflammation index,according to which a nomogram was constructed with concordance index(C-index) of 0.737 (95% CI: 0.667 to 0.806). The C-index of external verification was 0.674 (95% CI:0.569 to 0.779). The calibration prediction curve was in good agreement with the reference curve. The results of the clinical decision curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set at about 0.32,the maximum net benefit could be obtained by 0.11,and the cost/benefit ratio was 1∶2. The results of the clinical influence curve showed that when the risk threshold for high lymph node metastases in the nomogram was set to about 0.6,the probability of correctly predicting lymph node metastasis could reach more than 90%. There were no significant differences in overall survival time between patients with high/low risk of lymph node metastasis assessed by the nomogram and those with pathologically confirmed lymph node metastasis or without lymph node metastasis (Log-rank test: P=0.082 and 0.510,respectively). Conclusion:The prediction accuracy of the preoperative nomogram for ICC lymph node metastasis based on inflammation-related markers is satisfactory,which can be used as a supplementary method for the preoperative diagnosis of lymph node metastasis and is helpful for clinicians to make a personalized decision about lymph node dissection for patients with ICC.