This phase II trial is studying how well sunitinib works in treating patients with myelodysplastic syndromes or chronic myelomonocytic leukemia. Sunitinib may stop the growth of abnormal cells by blocking some of the enzymes needed for cell growth.

OBJECTIVES:

I. Determine the overall response rate (complete response, partial response, or hematological improvement) in patients with intermediate-2 or high-risk myelodysplastic syndromes or chronic myelomonocytic leukemia treated with sunitinib malate.

II. Determine the duration of response in patients treated with this drug. III. Determine the overall survival of patients treated with this drug. IV. Determine the progression-free survival of patients treated with this drug. V. Determine the time to disease progression in patients treated with this drug.

VI. Determine the toxicity of this drug in these patients.

OUTLINE: This is a multicenter study.

Patients receive oral sunitinib malate once daily on days 1-28. Courses repeat every 4 weeks in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed at 3-4 weeks and then monthly thereafter.

Inclusion Criteria:

• MDS syndromes meeting 1 of the following: Intermediate-2 disease, high-risk disease (IPSS score>=1.5)
• CMML: WBC>12,000/mm^3, Intermediate-2 disease with WBC=<12,000/mm^3, high-risk disease (IPSS score>=1.5) with WBC=<12,000/mm^3
• Patients with insufficient/inadequate metaphases for cytogenetic analysis are eligible if bone marrow blasts are >10% and/or 2-3 cytopenias are present
• No known brain metastases
• Life expectancy>12 weeks
• ECOG PS 0-2/Karnofsky PS 60-100%
• Calcium=<3.0 mmol/L
• Bilirubin normal
• AST and ALT=<2.5 times upper limit of normal
• Creatinine normal/creatinine clearance>=60 mL/min

Exclusion Criteria:

• No history of significant ECG abnormalities including but not limited to: ventricular arrhythmias (ventricular tachycardia, ventricular fibrillation>=3 beats in a row); QTc prolongation (i.e.QTc interval>=500msec)
• No history of allergic reaction to compounds of similar chemical/biological composition to sunitinib malate
• No NYHA class III-IV congestive heart failure
• Patients with history of NYHA class II congestive heart failure who are asymptomatic on treatment are eligible
• No abdominal fistula/G perforation/intraabdominal abscess within past 28 days
• No serious cardiovascular disease within past 12 months including: cerebrovascular accident or transient ischemic attack, myocardial infarction, cardiac arrhythmia, stable or unstable angina, symptomatic congestive heart failure, coronary or peripheral artery bypass graft or stenting
• No pulmonary embolism within past 12 months
• No uncontrolled hypertension (systolic BP>=140 mmHg/diastolic BP>=90 mmHg)
• No condition impairing ability to swallow/retain sunitinib malate tablets including: GI tract disease resulting in inability to take oral medication, requirement for IV alimentation, prior surgical procedures affecting absorption, active peptic ulcer disease
• No serious/nonhealing wound, ulcer, or bone fracture
• No uncontrolled pre-existing thyroid abnormality
• No concurrent uncontrolled illness including ongoing/active infection
• No psychiatric illness/social situation that would preclude study participation
• Not pregnant/nursing
• Negative pregnancy test
• Fertile patients must use effective barrier contraception
• 4 weeks since prior major surgery
• Prior central thoracic radiotherapy that included heart in radiotherapy port allowed provided NYHA congestive heart failure=\