Zidovudine, Interferon Alfa-2b, PEG-Interferon Alfa-2b in Patients With HTLV-I Associated Adult T-Cell Leukemia/Lymphoma

RATIONALE: Human T-cell lymphotropic virus type 1 (HTLV-1) can cause cancer. Zidovudine is an antiviral drug that acts against the human T-cell lymphotropic virus type 1. Giving zidovudine, interferon alfa-2b, and PEG-interferon alfa-2b together may stimulate the immune system and slow down or keep the cancer cell from growing. PURPOSE: This clinical trial is studying how well giving zidovudine together with interferon alfa-2b and PEG-interferon alfa-2b works in treating patients with human T-cell lymphotropic virus type 1-associated adult T-cell leukemia/lymphoma.

OUTLINE: This is a multicenter study. * Induction therapy: Patients receive zidovudine IV twice daily on days 1-14, and recombinant interferon alfa-2b IV twice daily on days 3-14. Patients achieving clinical complete response (CR) proceed to part 1 maintenance therapy; patients achieving partial response (PR) receive another 7 days of zidovudine and recombinant interferon alfa-2b and then proceed to part 1 maintenance therapy. * Part 1 maintenance therapy: Patients receive oral zidovudine twice daily and PEG-interferon alfa-2b subcutaneously (SC) once weekly, beginning on day 14 or 21 and continue to day 60. Patients are evaluated after completion of part 1 maintenance therapy and proceed to part 2 maintenance therapy. * Part 2 maintenance therapy: Patients achieving CR with undetectable clonal disease proceed to group A; patients achieving CR with minimal residual disease (by PCR) or PR proceed to group B. * Group A: Patients receive oral zidovudine twice daily and PEG-interferon alfa-2b SC once weekly. Treatment continues in the absence of disease progression or unacceptable toxicity. * Group B: Patients receive oral zidovudine twice daily and PEG-interferon alfa-2b SC once weekly for 12 weeks and undergo reevaluation. Patients in continued CR with minimal residual disease or stable PR receive oral valproic acid twice daily, PEG-interferon alfa-2b SC once weekly, and oral zidovudine twice daily for 6 months. At that point (month 9) patients with no detectable clonal disease continue their previous treatment, while patients with minimal residual disease receive PEG-interferon alfa-2b SC and oral zidovudine twice daily in the absence of disease progression or unacceptable toxicity. Blood samples are collected at baseline, days 1 and 2, and months 3, 6, and 12 for protein, genomic DNA, and RNA analysis. Baseline molecular characteristics of the tumor and tumor response to treatment is assessed. After completion of study treatment, patients are followed every 3 months for 1 year.