The increasing evidences suggest that Immunoscore(IS), a combinatorial density analysis of CD8+ and CD3+ cells in the centre and invasive margin of tumour (CT and IM), has an advantage over the currently used tumour staging methods in a variety of tumours; however, IS in hepatocellular carcinoma remains unreported. In this study, IS was performed on serial sections from two HCC cohorts (total 449) and compared with current tumour staging systems. Kaplan-Meier curves illustrate a positive association between a higher IS (IS≥2) and longer survival of HCC patients. Although the IS was highly related to the outcome of patients, however, IS seems not to be the optimal prognostic factor when compared with the CD8CT. As noted, among CD8CT, CD8IM, CD3CT, CD3IM and IS, CD8CT, as an independent indicator, demonstrated the highest prognostic impact on both DFS and OS in our Cox multivariate regression analysis (P< 0.0001). In our study, the minimum cut-off value was 93 CD8CT cells per mm2, to be used to divide the patients into CD8CTHi group and CD8CTLo group in clinical settings. Our results suggest that CD8CT densities analysis notably improved the accuracy of survival prediction with convenience of clinical manipulation in HCC.
Keywords: CD8+ T cells; HCC; Immunoscore; TNM; prognostic indicator.