Pathologically confirmed diagnosis of CD20-positive diffuse large B-cell lymphoma
60\~80 years old
Ann Arbor stage I\~IV
ECOG physical score of 0\~2
Have not received previous treatment to lymphoma, including chemotherapy, radiotherapy, or biotherapy
Have at least one clinically measurable lesion: \>= 2cm under physical examination, or \>= 1.5cm under computed tomography (CT) or magnetic resonance (MR)
Life expectancy of \>= 3 months
Serum glutamic oxaloacetic transaminase (SGOT) and serum glutamate pyruvate transaminase and total bilirubin \<= 2 × upper limit of normal (ULN)
