The purpose of this study is to collect and store normal and malignant tissue from patients with gastric cancer, GIST, esophageal cancer, pancreas cancer, hepatocellular cancer, biliary cancer, neuroendocrine, peritoneal mesothelioma, anal cancer and colorectal cancer, an estimated 50 to 100 of each tumor type. To collect and store blood samples from patients with gastric cancer, GIST, esophageal cancer, pancreas cancer, hepatocellular cancer, biliary cancer, neuroendocrine, peritoneal mesothelioma, anal cancer and colorectal cancer. To create a database for the collected tissue and allow access to relevant clinical information for current and future protocols. To create tissue microarrays for each gastrointestinal cancer subtype, namely, gastric cancer, GIST, esophageal cancer, pancreas cancer, hepatocellular cancer, biliary cancer, neuroendocrine, peritoneal mesothelioma, anal cancer and colorectal cancer, to facilitate future molecular studies. To grant access to Dr Kindler, Dr. Salgia, and Dr. Catenacci to this database (as it is being acquired) of the coupled patient tissue samples (normal and malignant) and relevant clinical information for the investigation of tyrosine kinases, such as Met and Ron, receptor tyrosine kinase family members, STATs, paxillin, focal adhesion proteins, cell motility/migration proteins, tyrosine/serine/threonine kinase family members, related molecules, and downstream targets implicated in the pathogenesis of GI cancers. Examples of molecular testing include evaluation of DNA mutation, alternative splice variants, protein expression and phosphorylation, and immunohistochemistry on samples. These studies will be correlated with clinical information as stated above.