Prognostic role of neutrophil-to-lymphocyte ratio in unresectable hepatocellular cancer patients treated with trans-arterial chemoembolization

The neutrophil-to-lymphocyte ratio (NLR), a useful biomarker, reflects systemic inflammation responses which are closely associated with the prognosis of various malignancies. Nevertheless, the prognostic significance of NLR in patients with hepatocellular carcinoma (HCC) undergoing trans-arterial chemoembolization (TACE) remains controversial. The study was designed to determine the prognostic value of NLR in survival outcomes of HCC patients receiving TACE by systematical review of present literature. Medline, Embase, Web of Science and Cochrane library databases were searched according to a pre-specified inclusive strategy to identify studies concerning survival in HCC patients receiving TACE with high or low pre- or post-TACE NLR. An electronic Excel table was used to extract epidemiological information, clinical pathological characteristics as well as primary outcome data. Initially, 598 relevant articles were selected, of which, 13 articles including 1,648 unresectable HCC patients undergoing TACE were ultimately enrolled. Our review and meta-analysis demonstrated that a high pre-TACE NLR reflected unfavorable overall survival (OS) [pooled hazard ratio (HR): 1.53, pooled 95% confidence interval (CI): 1.29-1.78, P<0.001], but had no significant prognostic relationship with progression free survival (PFS) (P>0.05) and tumor response (P=0.088). A high post-TACE NLR was closely associated with metastasis (OR: 1.57, 95% CI: 0.732-3.382, P=0.246), but not with time to progression (TTP) (P=0.18) and tumor response (P=0.229), and controversial role with OS (P value: 0.001 vs. 0.342). The NLR change trend between pre- and post-TACE was not correlated with either tumor response to TACE (P=0.89) or hepatic progression (P=0.55), whereas its prognostic role with OS was also controversial (P>0.05 or <0.05). As a convenient, inexpensive and easily available inflammatory biomarker, NLR harbored its important value in prognostic prediction in patients with unresectable HCC undergoing TACE. However, the association of the changing trends of NLR and NLR at different stages with different prognostic endpoints in HCC patients undergoing TACE was still in controversy, therefore further large-scale, prospective studies are needed to confirm these findings.