MabThera (Rituximab) in Combination With CHOP (or CHOP-like) Chemotherapy in Patients With Aggressive B-Cell Lymphoma

Inclusion Criteria: * Histologically confirmed cluster of differentiation antigen 20 (CD20) positive Diffuse Large B-Cell Lymphoma according to the World Health Organization/Revised European-American Classification of Lymphoid Neoplasms (WHO/REAL) classification * Age \> or =18 years * Performance status \< or = 2 on the Eastern Cooperative Oncology Group (ECOG) scale * Women of child-bearing potential must agree to use effective contraception for the entire treatment period and during the 12 months thereafter Exclusion Criteria: * Transformed lymphoma (secondary to "low-grade" follicular lymphoma) * Grade 1, 2 or 3a follicular lymphoma * Primary or secondary central nervous system (CNS) involvement * Patients with prior or concomitant malignancies except non-melanoma skin cancer or adequately treated in situ cervical cancer * Major surgery (excluding lymph node biopsy) within 28 days prior to registration. * Poor renal function: Serum creatinine \> 2.0 mg/dl (177 micromol/L) * Pregnancy * Poor hepatic function: total bilirubin \> 2.0 mg/dl (34 micromol/L), aspartate transaminase (AST) (serum glutamic oxaloacetic transaminase \[SGOT\]) or alanine transaminase (ALT) (serum glutamic pyruvic transaminase \[SGPT\]) or alkaline phosphatase (AP) \> 3 x the upper limit of normal unless these abnormalities are related to lymphoma. * Known human immunodeficiency virus (HIV) infection or active viral hepatitis, specifically hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. * Serious underlying medical conditions, which could impair the ability of the patient to participate in the trial * Life expectancy \< 6 months * Known sensitivity or allergy to murine products * Treatment within a clinical trial within 30 days prior to trial entry