IDO and intra-tumoral neutrophils were independent prognostic factors for overall survival for hepatocellular carcinoma

BACKGROUND: Both Indole-amine-2,3-dioxygenase (IDO) and neutrophils were proved to have pro-tumor effect in some kinds of solid tumors by immune suppression. However, little is known about their effect on hepatocellular carcinoma (HCC) and the relationship between these two immune-suppressive factors. The aim of this study was to evaluate the prognostic significance of IDO and intra-tumoral neutrophils and their correlations in HCC. METHODS: Specimens' tissue microarray (TMA) for 153 HCC patients was used in this study. We examined intra-tumoral expression of IDO and CD66b in TMA. The Kaplan-Meier method and Cox regression models were used to evaluate the prognostic value of IDO expression and CD66b. RESULTS: Multivariate analysis showed both IDO expression and intra-tumoral neutrophils infiltration were independent prognostic factors for overall survival (OS). In high IDO expression group, the percentage of intra-tumoral neutrophils infiltration was higher than that in low IDO expression group. CONCLUSION: Both IDO and intra-tumoral neutrophils were independent prognostic factors for overall survival for HCC.