Sunitinib in Treating Patients With Stage I, Stage II, or Stage III Breast Cancer Who Have Tumor Cells in the Bone Marrow

Pilot Study to Evaluate the Effect of Sunitinib on Occult Tumor Cells in the Bone Marrow of Patients With High Risk Early Stage Breast Cancer

RATIONALE: Sunitinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor.

PURPOSE: This phase II trial is studying how well sunitinib works in treating patients with stage I, stage II, or stage III breast cancer who have tumor cells in the bone marrow.

OBJECTIVES:

Primary

• To determine the effect of sunitinib malate on occult tumor cells (OTC) in the bone marrow of patients with high-risk stage I-III breast cancer.

Secondary

• To evaluate the number of patients who are able to tolerate this drug for 6 months and complete the study.
• To evaluate the toxicities of this drug in these patients.
• To evaluate the effects of this drug on OTC in peripheral blood.
• To evaluate correlative markers, including endothelial cells, soluble cKIT, and VEGF.
• To evaluate relapse-free and overall survival of patients treated with this drug.

OUTLINE: Patients receive oral sunitinib malate once daily for 6 months in the absence of disease progression or unacceptable toxicity.

Patients undergo bone marrow aspiration and peripheral blood sample collection at baseline and at 6 and 12 months. Bone marrow aspirate samples are analyzed by IHC and flow cytometry. Peripheral blood samples are analyzed for circulating tumor cells.

After completion of study treatment, patients are followed at 1 and 6 months.

DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed high-risk breast cancer

  • Stage I-III disease

• Has undergone definitive surgery with or without radiotherapy

  • Completely resected disease

• Bone marrow aspirate positive for occult tumor cells, defined as ≥ 10 occult tumor cells/mL by IHC and flow cytometry

  • If the patient received either no adjuvant therapy or hormonal therapy alone, the aspiration may have been performed at diagnosis as part of the large micrometastasis study at UCSF, or following diagnosis if the patient underwent initial surgery elsewhere (or underwent surgery following neoadjuvant therapy for breast cancer)
  • If the patient received adjuvant chemotherapy, the aspiration must have been performed ≥ 3 weeks after completion of chemotherapy

• Hormone receptor status not specified

PATIENT CHARACTERISTICS:

• Menopausal status not specified
• ECOG performance status 0-1
• WBC count normal (3.4-10 x 10^9/L)
• Hemoglobin > 9.0 g/dL
• Platelet count normal (140-450 x 10^9/L)
• ANC normal (1.8-6.8 x 10^9/L)
• Serum creatinine ≤ 1.5 times upper limit of normal (ULN)
• Total bilirubin ≤ 1.5 times ULN
• Alkaline phosphatase ≤ 1.5 times ULN
• AST and ALT ≤ 2.5 times ULN
• TSH and T4 levels normal
• LVEF > 50%
• Systolic BP < 140 mm Hg and diastolic BP < 90 mm Hg
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No history of HIV infection
• No concurrent severe illness that would likely preclude study compliance
• No other malignancy within the past 5 years except basal cell carcinoma of the skin

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• No prior sunitinib malate
• Prior adjuvant chemotherapy, including trastuzumab (Herceptin®), allowed provided it was completed within the past 6 months
• Prior surgery following neoadjuvant chemotherapy or hormonal therapy allowed
• No concurrent potent CYP3A4 inducers
• No concurrent trastuzumab
• Concurrent hormonal therapy or radiotherapy allowed