IL6 and Epstein-Barr virus infection: The univariate analysis showed that stage III-IV, B symptoms, bone marrow involvement, IPI ≥3, ECOG ≥3, decreased albumin, EBV infection, Extra-nodal ≥1, HPS, IL-10 ≥3.6 pg/ml, IL-6 ≥2.2 pg/ml, IFN γ ≥3.0 pg/ml, decreased LDH and decreased serum ferritin were prognostic indicators of OS (Table 4, Figures 2C, E).