ObjectiveTo investigate the effect of the expression level of diacylglycerol kinase gamma (DGKγ) in paracancerous tissue on the postoperative prognosis of patients with hepatocellular carcinoma (HCC) and its clinical value. MethodsRelated clinical data were collected from 78 HCC patients who were admitted and underwent surgical resection from December 2008 to August 2012 in the Affiliated Cancer Hospital of Zhengzhou University. Quantitative real-time PCR was used to measure the mRNA expression level of DGKγ in paracancerous tissue, and then the 78 patients were divided into low expression group (DGKγ ＜0.086 2, LEP group) and high expression group (DGKγ ≥0.086 2, HEP group). Basic data and clinical features were compared between the two groups. The t-test and the Mann-Whitney U test were used for comparison of continuous data, and the chi-square test and the corrected chi-square test were used for comparison of categorical data. Univariate and multivariate Cox regression analyses were used to investigate independent influencing factors for survival and prognosis, and the Kaplan-Meier method was used to analyze the overall survival trends of all patients and the LEP and HEP groups in each subgroup of Barcelona Clinic Liver Cancer (BCLC) stages. ResultsThe multivariate Cox regression analysis showed that the expression level of DGKγ (HR=1.913，95%CI： 1.111-3.296，P=0.019), HBsAg (HR=2.645，95%CI：1.264-5.537，P=0.010), Alb (HR=0.952，95%CI：0.916-0.990，P=0.013), BCLC stage (HR=1.702，95%CI：1267-2.286，P＜0001) and tumor size (HR=1.083，95%CI：1.019-1.152，P=0011) were independent influencing factors for long-term survival of HCC patients； the LEP group had a significantly longer median survival time than the HEP group (45.0 months vs 22.9 months, P=0002 5). The stratified analysis showed that for BCLC stage A HCC, the LEP group had significantly better long-term survival than the HEP group (P=0.034 5); for BCLC stage B/C HCC, the LEP group had a longer median survival time than the HEP group (16.5 months vs 10.8 months), but there was no significant difference in short- and long-term survival between the two groups (P＞0.05). ConclusionThe expression level of DGKγ in paracancerous tissue may be a new index for predicting and evaluating the long-term survival risk of HCC patients after surgery and has certain value in clinical application.