Dasatinib in Treating Patients With Unresectable or Metastatic Squamous Cell Skin Cancer or RAI Stage 0-I Chronic Lymphocytic Leukemia

This phase II trial is studying how well dasatinib works in treating patients with unresectable or metastatic squamous cell skin cancer or RAI Stage 0-I chronic lymphocytic leukemia. Dasatinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

PRIMARY OBJECTIVES: I. Determine the objective response rate (complete response and partial response) in patients with unresectable or metastatic squamous cell carcinoma of the skin or RAI stage 0-I chronic lymphocytic leukemia receiving dasatinib. SECONDARY OBJECTIVES: I. Determine the progression-free survival of patients receiving this drug. II. Evaluate tumor for presence of total EphA2 and both total and active Src and FAK by immunohistochemistry (IHC) pre-treatment with dasatinib. III. Evaluate tumor for presence of cyclooxygenase-2 by IHC pre-treatment with dasatinib. OUTLINE: Patients are assigned to 1 of 2 treatment arms. ARM I: Patients receive 100 mg dasatinib orally (PO) twice daily (BID) on days 1-28. ARM II (PATIENTS ENROLLED AFTER 11/18/08): Patients receive 70 mg dasatinib PO BID on days 1-28. In both arms, courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. Pre-therapy tumor biopsy specimens are collected to detect total and phosphorylated Src and FAK, total EphA2, and cyclooxygenase-2 by immunohistochemistry. After completion of study treatment, patients are followed up monthly for up to 12 weeks.