DISEASE CHARACTERISTICS:

• Diagnosis of myelofibrosis with myeloid metaplasia, including any of the following subtypes:

  • Agnogenic myeloid metaplasia
  • Post-polycythemic myeloid metaplasia
  • Post-thrombocythemic myeloid metaplasia

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• Not specified

Hematopoietic

• Absolute neutrophil count ≥ 1,000/mm^3
• Platelet count ≥ 100,000/mm^3
• Hemoglobin ≤ 10 g/dL OR
• Transfusion dependent

Hepatic

• Total or direct bilirubin ≤ 2.0 mg/dL
• AST ≤ 3 times upper limit of normal (unless due to hepatic extramedullary hematopoiesis)
• No hepatitis A, B, or C infection

Renal

• Creatinine ≤ 2.0 mg/dL

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No known HIV positivity
• No condition or laboratory abnormality that would preclude study participation
• No other active malignancy
• No known hypersensitivity to thalidomide or lenalidomide

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior lenalidomide
• At least 28 days since prior interferon alfa, thalidomide, or growth factors
• No concurrent growth factors

Chemotherapy

• At least 28 days since prior chemotherapy
• At least 28 days since prior hydroxyurea

Endocrine therapy

• At least 28 days since prior systemic corticosteroids

Radiotherapy

• Not specified

Surgery

• Not specified

Other

• Recovered from prior therapy
• At least 28 days since prior anagrelide or other myelosuppressive agents
• At least 28 days since prior experimental therapy