Tumor necrosis factor (TNF)-alpha and interleukin (IL)-10 are key cytokines involved in lymphoma development. Their pretreatment plasma levels were reported to influence the clinical course of non-Hodgkin's lymphoma. In this study the impact of combined elevation of TNF-alpha and IL-10 on disease features and outcome of patients with diffuse large B-cell lymphoma (DLBCL) were investigated. Plasma TNF-alpha and IL-10 levels were determined at the time of diagnosis in a group of 106 DLBCL patients uniformly treated with anthracycline-based regimens. Three risk groups depending on the pretreatment levels of the cytokines were identified: low-, intermediate-, and high-risk groups. In univariate analysis, the cytokine intermediate- and high-risk groups were associated with lower probability of achieving a complete remission (odds ratio [OR] = 0.2, 95% confidence interval [CI] 0.06-0.6, p = 0.006 and OR = 0.05, 95% CI 0.01-0.2, p < 0.0001, respectively) and shorter progression-free survival (PFS) (OR = 4.4, 95% CI 1.9-10.2, p < 0.001 and OR = 9.7, 95% CI 4.1-23.0, p < 0.0001, respectively) and overall survival (OS) (OR = 4.2, 95% CI 1.7-10.1, p = 0.002 and OR = 11.2, 95% CI 4.4-28.4, p < 0.0001, respectively) in comparison with the cytokine low-risk group. In multivariate analysis, the cytokine intermediate- and high-risk groups also correlated with shorter PFS (relative risk [RR] = 4.5, 95% CI 1.9-10.9, p = 0.001 and RR = 5.8, 95% CI 2.2-15.3, p < 0.0001, respectively) and OS (RR = 4.6, 95% CI 1.8-12.0, p = 0.001 and RR = 7.5, 95% CI 2.7-20.9, p < 0.0001, respectively) regardless of the International Prognostic Index (IPI) scoring system. The TNF-alpha and IL-10 level-based index may work as an additional model to the IPI for predicting the survival of DLBCL patients. This model may help to identify patients in a given IPI risk group for whom more accurate and risk-adapted treatment could be advised.