Interferon Alfa in Treating Children With HIV-Related Cancer

DISEASE CHARACTERISTICS: * Histologically proven malignancy diagnosed at any time following confirmation of HIV-positivity, including the following: * Leukemia * Non-Hodgkin's lymphoma * CNS lymphoma * Other solid tumors * Measurable disease * Concurrent registration on protocol POG-9182 required * Confirmed HIV-positive by POG-9182 criteria * Required biology studies completed PATIENT CHARACTERISTICS: Age: * 21 and under Performance status: * Not specified Life expectancy: * More than 4 weeks Hematopoietic: * Absolute neutrophil count at least 1,000/mm\^3 * Platelet count at least 100,000/mm\^3 (unless bone marrow involvement present) Hepatic: * See Disease Characteristics * Bilirubin less than 1.5 times normal * SGPT and SGOT less than 2 times normal (may discuss with Study Coordinator) Renal: * Creatinine less than 1.5 mg/dL Cardiovascular: * Adequate cardiac function by echocardiogram/MUGA scan Other: * Chronically infected patients must be stable enough to meet life expectancy requirement PRIOR CONCURRENT THERAPY: Biologic therapy: * No prior interferon for cancer * Prior interferon alfa for viral infections (i.e., hepatitis) must be discussed with Study Coordinator Chemotherapy: * At least 1 week since prior chemotherapy Endocrine therapy: * Not specified Radiotherapy: * At least 1 week since prior radiotherapy Surgery: * Not specified Other: * Prior antiretroviral therapy allowed * At least 1 week since prior acute treatment for any serious or life-threatening infection * No concurrent local treatment unless discussed with the Study Coordinator * No concurrent acute treatment for any serious or life-threatening infection * Concurrent antiretroviral therapy allowed