DISEASE CHARACTERISTICS: Pathologically confirmed acute promyelocytic leukemia in one of the following categories: First complete remission following induction retinoids First complete remission following induction chemotherapy and not eligible for additional consolidation chemotherapy Second or subsequent remission following induction retinoids or chemotherapy Clinically complete remission following consolidation chemotherapy and: Detectable minimal residual disease by reverse transcription-polymerase chain reaction (RT-PCR) assay Not eligible for bone marrow transplant Molecular remission (i.e., negative RT-PCR assay) with subsequent evidence of early molecular relapse (i.e., normal peripheral blood counts, normal bone marrow morphology, and positive RT-PCR assay)