Oblimersen, Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone in Treating Patients With Stage II, Stage III, or Stage IV Diffuse Large B-Cell Lymphoma

DISEASE CHARACTERISTICS: Histologically confirmed* CD20+ diffuse large B-cell lymphoma, including any of the following stages: Extensive stage II (not radio-encompassable within a single involved field or not a candidate for brief chemotherapy and radiotherapy) Bulky stage II (any single mass greater than 10 cm) Stage III Stage IV NOTE: *Confirmed by tissue biopsy Previously untreated disease Measurable disease At least 2 cm by imaging studies Circulating lymphoma cells no greater than 5,000/mm^3 No history of other lymphoproliferative disorder No history of indolent lymphoma No T-cell lymphoma No CNS involvement No post-transplantation lymphoproliferative disorder PATIENT CHARACTERISTICS: Age 19 and over Performance status ECOG 0-2 Life expectancy Not specified Hematopoietic Absolute neutrophil count at least 1,500/mm^3 (unless due to bone marrow involvement with lymphoma) Platelet count at least 100,000/mm^3 (unless due to splenomegaly or bone marrow involvement with lymphoma) Hepatic Bilirubin no greater than 3 mg/dL (unless due to lymphoma) No known hepatitis B virus Renal Creatinine no greater than 2 mg/dL (unless due to lymphoma) Cardiovascular No cardiac contraindication to doxorubicin therapy (e.g., abnormal contractility on echocardiography) History of cardiac disease allowed provided ejection fraction is normal Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception Adequate venous access HIV negative No other malignancy within the past 5 years except adequately treated nonmelanoma skin cancer, localized basal cell or squamous cell skin cancer, or curatively treated carcinoma in situ of the cervix No neurological contraindication to vincristine (e.g., peripheral neuropathy) No active systemic infection No medical condition that would compromise study treatment, add toxicity, or impair assessment PRIOR CONCURRENT THERAPY: Biologic therapy Not specified Chemotherapy No prior systemic chemotherapy Endocrine therapy Not specified Radiotherapy No prior radiotherapy Prior radiotherapy for localized basal cell or squamous cell skin cancer used with curative intent allowed Surgery Not specified