Neutrophil-to-Lymphocyte Ratio: A Systemic Inflammatory Index for Primary Diagnosis and Prognosis of Cholangiocarcinoma

Abstract

Cholangiocarcinoma (CCA) is a major cause of cancer death in the northeastern Thailand. A primary diagnosis for CCA is essential to reduce the mortality of CCA patients. In this study, the Neutrophil-to-Lymphocyte ratio (NLR) was demonstrated for the first time to be a potential primary diagnostic index for CCA. NLR was determined in parallel with serum CA19-9, in histologically proven CCA patients (n=103) and non-CCA subjects (n = 217). CCA patients exhibited significantly higher NLRs (mean ± SD, 4.88 ± 3.95) than the non-CCA subjects (2.34 ± 1.63) (P <0.001). NLR had diagnostic power for CCA with an area under curve (AUC) of 0.773, comparable with that of CA19-9. A cut-off NLR at 2.3 provided diagnostic values for CCA with 70.9% sensitivity, 69.1% specificity, and 69.7% accuracy. Furthermore, a high NLR (> 2.3) was associated with larger tumor sizes, shorter survival of CCA patients (P = 0.001) and was suggested to be an independent poor prognostic indicator for CCA. In conclusion, besides being an indicator of poor prognosis, NLR is as good as serum CA19-9 in discriminating CCA from non-CCA conditions. This suggested the potential of using NLR as a primary diagnostic indicator of CCA, especially in the peripheral clinics where advanced biomarkers cannot be offered.