To investigate the diagnostic value of neutrophil/lymphocyte ratio (NLR) combined with CA19-9 for intrahepatic cholangiocarcinoma (ICC).

70 ICC patients (ICC group), 80 patients with benign bile duct lesions (benign lesion group) and 80 healthy subjects (control group) admitted to the Third Affiliated Hospital of Sun Yat-sen University from January 2012 to October 2017 were enrolled. The informed consents of all patients were obtained and the local ethical committee approval was received. In the ICC group, 44 patients were male and 26 female, aged (54±12) years on average. In the benign lesion group, 54 cases were male and 26 female, aged (55±13) years on average. In the control group, 52 patients were male and 28 female, aged (51±10) years on average. Upon the initial admission, blood routine test, CA19-9 and CA125 of the patients were collected and NLR and platelet/lymphocyte ratio (PLR) were calculated. The diagnostic efficiency of single and combined parameters for ICC was evaluated by the ROC curve.

The area under ROC curve of NLR, PLR, CA19-9 and CA125 in diagnosis of ICC was 0.848, 0.780, 0.881 and 0.860, respectively. The diagnostic threshold values were 2.3, 168, 19 kU/L and 21 kU/L, respectively. The sensitivity of NLR, PLR, CA19-9 and CA125 was 0.81, 0.51, 0.74 and 0.67, respectively. The specificity of NLR, PLR, CA19-9 and CA125 was 0.86, 0.91, 0.98 and 0.90, respectively. The area under ROC curve of NLR+PLR, NLR+CA19-9, NLR+CA125 and CA19-9+CA125 was 0.857, 0.963, 0.927 and 0.938, respectively. The sensitivity was 0.86, 0.96, 0.93 and 0.89, and the specificity was 0.81, 0.88, 0.84 and 0.88, respectively.

Single detection of NLR, PLR, CA19-9 and CA125 is of certain value in the diagnosis of ICC with relatively high diagnostic efficiency. However, the combined detection of NLR and CA19-9 yields better diagnostic value compared with single parameter.