II. To define overall survival distribution from initiation of dasatinib. III. To define duration of response. IV. To determine if there is a correlation between clinical benefit from dasatinib (defined as disease response or stabilization) and pharmacokinetics, pharmacodynamics (phosphorylated Src [pSrc] expression in platelets), or changes in serum levels of cytokines, growth factors, and growth factor receptors relevant to the Src signaling pathway.