EPOCH and Rituximab to Treat Non-Hodgkin's Lymphoma in Patients With HIV Infection

Background: * Human immunodeficiency virus (HIV)-infected patients have a weakened immune system, and chemotherapy, which is used to treat lymphoma, probably causes further damage to the immune system. * Limiting the amount of immune damage due to chemotherapy might decrease the number of infections and the risk of developing cancer in the future in HIV-infected patients with non-Hodgkin's lymphoma. Objectives: * To determine whether reducing the total amount of chemotherapy using a specific combination of drugs called EPOCH-R (etoposide, doxorubicin, vincristine, cyclophosphamide and rituximab) will rid the body of lymphoma quickly while decreasing the risk of infections and future cancers. * To determine whether the lymphoma will remain undetectable for at least one year if treatment is stopped one cycle after the patient enters remission. Eligibility: -Patients with non-Hodgkin's lymphoma and HIV infection 4 years of age and older who have not been treated previously with rituximab or cytotoxic chemotherapy. Design: * Patients receive EPOCH-R in 3-week treatment cycles for at least three and no more than six cycles. * The lymphoma is evaluated using computed tomography (CT) and positron emission tomography (PET) scans at the end of treatment cycles 2 and 3. A bone marrow biopsy is repeated after cycle 2 if a biopsy was initially positive on screening for participation in the study. * Anti-HIV therapy is stopped before chemotherapy begins and is restarted when EPOCH-R treatment ends. * Patients are monitored for treatment response with blood tests and imaging scans at baseline, when treatment ends, 2 months after treatment ends and then every 3 to 6 months for a total of 24 months following chemotherapy.