['Several biomarkers indicating poor prognosis have been reassessed in patients receiving rituximab combination chemotherapy for diffuse large B-cell lymphoma (DLBCL). However, few studies have investigated outcome in relation to a combination of these biomarkers. In addition, no large-scale studies have reassessed the outcome of patients with CD5-positive DLBCL treated with rituximab.', 'We conducted a retrospective study and investigated the predictive value of three biomarkers -- BCL2, germinal center (GC) phenotype and CD5 -- in 121 DLBCL patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone.', 'CD5-positive patients showed significantly poorer event-free survival (EFS) and overall survival (OS) than CD5-negative patients (2-year EFS, 18% versus 73%, P < 0.001; 2-year OS, 45% versus 91%, P = 0.001). However, no significant difference in outcome according to BCL2 or GC phenotype was observed. Multivariate analysis revealed that CD5 expression was a significant prognostic factor for EFS [hazard ratio 14.2, 95% confidence interval (CI) 4.7-43.2] and OS (hazard ratio 20.3, 95% CI 3.6-114.4).'] Is cD5 expression potentially predictive of poor outcome among biomarkers in patients with diffuse large B-cell lymphoma receiving rituximab plus CHOP therapy?