RATIONALE: Drugs such as flt3L may stimulate a person's immune system and help kill cancer cells. It is not yet known if flt3L is effective in treating acute myeloid leukemia.

PURPOSE: Randomized phase III trial to determine the effectiveness of flt3L in treating patients who have acute myeloid leukemia that is in remission.

OBJECTIVES:

• Compare the failure-free survival and overall survival in patients with acute myeloid leukemia in complete remission treated with maintenance flt3 ligand vs observation alone.
• Compare the long-term immunologic effects of these regimens in these patients.
• Compare the long-term safety and toxicity of these regimens in these patients.

OUTLINE: This is a randomized study. Patients are stratified according to complete remission (CR) (first vs second vs third or subsequent) and post-remission therapy (yes vs no). Patients are randomized to one of two treatment arms.

• Arm I: Patients receive flt3 ligand subcutaneously daily on days 1-14. Treatment repeats every 4 weeks for 6 courses in the absence of disease progression or unacceptable toxicity.
• Arm II: Patients undergo observation alone. Patients begin treatment or observation within 4 weeks after documentation of CR after induction therapy or within 4 weeks after discharge from hospital after post-remission therapy.

Patients are followed every 3 months for 2 years, every 6 months for 3 years, and then annually thereafter.

PROJECTED ACCRUAL: A total of 139 patients will be accrued for this study within approximately 28 months.

DISEASE CHARACTERISTICS:

• Diagnosis of acute myeloid leukemia in first, second, third, or subsequent complete remission (CR)

  • Must be at least 60 years of age if first CR

  • Must have had histological proof (from bone marrow aspirate, smears, or touch preps of marrow biopsy) of one of the following prior to achieving CR:

    • Acute myeloblastic leukemia (M0, M1, M2)
    • Acute promyelocytic leukemia (M3)
    • Acute myelomonocytic leukemia (M4)
    • Acute monocytic leukemia (M5)
    • Acute erythroleukemia (M6)
    • Acute megakaryocytic leukemia (M7)
    • Refractory anemia with excess blasts in transformation

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• ECOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Not specified

Hepatic:

• Bilirubin less than 3 times upper limit of normal (ULN)
• SGOT less than 3 times ULN

Renal:

• Creatinine less than 2 mg/dL

Cardiovascular:

• No clinically significant active cardiac disease

Pulmonary:

• No clinically significant active pulmonary disease

Other:

• Not pregnant or nursing
• Fertile patients must use effective contraception
• No uncontrolled or active autoimmune disease

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Prior autologous bone marrow transplantation (BMT) allowed
• No prior allogeneic BMT
• Other prior immunotherapy allowed if not received during the most recent treatment

Chemotherapy:

• Not specified

Endocrine therapy:

• Not specified

Radiotherapy:

• Not specified

Surgery:

• Not specified