Low counts of γδ T cells in peritumoral liver tissue are related to more frequent recurrence in patients with hepatocellular carcinoma after curative resection.

OBJECTIVES TCR- gamma-delta + T cells (γδ T cells) are non-conventional T lymphocytes that can recognize and eradicate tumor cells. Our previous studies showed that infiltration and function of γδT cells were substantially attenuated in hepatocellular carcinoma (HCC). However, their prognostic value was not clarified. METHODS The association between γδ T cells and the clinical outcomes was determined by immunohistochemistry (IHC) in a HCC patient cohort (n = 342). RESULTS Immunohistochemistry showed decreased infiltration of γδ T cells in tumoral tissues compared with paired peritumoral tissues. The counts of γδ T cells in peritumoral tissues were negatively correlated with tumor size (P = 0.005). Survival analysis showed that the levels of peritumoral γδ T cells were related to both time to recurrence (TTR) and overall survival (OS) (P = 0.010 and P = 0.036, respectively) in univariate analysis, and related to TTR in multivariate analysis (P = 0.014, H.R. [95% CI] = 0.682 [0.502-0.927]). Furthermore, the level of peritumoral γδ T cells showed independent prognostic value for TTR in Barcelona Clinic Liver Cancer (BCLC) stage A patients (P = 0.038, H.R. [95% CI] = 0.727 [0.537-0.984]). However, tumoral γδ T cells did not show independent prognostic value for either TTR or OS in HCC patients. CONCLUSIONS Low counts of γδ T cells in peritumoral liver tissue are related to a higher incidence of recurrence in HCC and can predict postoperative recurrence, especially in those with early-stage HCC.