Saracatinib in Treating Patients With Locally Advanced or Metastatic Stomach or Gastroesophageal Junction Cancer

PRIMARY OBJECTIVES: I. To assess the objective disease control rate (i.e., partial or complete response as defined by Response Evaluation Criteria in Solid Tumors (RECIST) criteria or stable disease for ≥ 16 weeks) in patients with locally advanced or metastatic adenocarcinoma of the stomach or gastroesophageal junction treated with AZD0530 (saracatinib). SECONDARY OBJECTIVES: I. To assess the median time to disease progression, median overall survival, and 1-year survival rate in these patients. II. To assess the toxicity of AZD0530 in these patients. III. To evaluate potential predictive markers by assessing pretreatment intratumoral levels of src, Y419 phospho-src (P-Src), and c-terminal src kinase (Csk) in archival tumor biopsies. OUTLINE: Patients receive saracatinib orally (PO) once daily (QD) in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at least every 2 months.