 Doctors at Memorial Sloan Kettering Cancer Center and at other institutions study normal and cancer cells. To study these cells we need to have human tissue, body fluids, and blood. The patient will be having or have had a procedure to remove tissue. The doctors would like to use some of this tissue. The doctors will use it for laboratory studies on the causes, prevention, diagnosis and treatment of sarcoma, gastrointestinal or other intra-abdominal cancers. They will only use extra tissue left over after all needed testing has been done. They would also like to study components of the immune blood cells and blood serum the liquid portion of the blood. In some patients they will take a blood sample before the tissue or body fluid is removed, usually at the same time that other routine pre-procedure blood tests are drawn. If thet need more blood, it will be drawn when the patient is seeing the doctor anyway. We will not draw more than 50cc 4-5 tablespoons at any one time. With the patients permission, thet may also send a small portion of the blood andor a sample of the tissue to a repository at the National Cancer Institute. This will be used to identify special proteins in the blood or tissue that may be useful for diagnosing cancer. Information about the treatment and the response to treatment may be linked to the tissue specimens obtained. This information may be important for the research studies that will be done on the tissue, body fluid and blood specimens. All of this information will be kept in strictest confidence; they will use it only for biomedical research. The patients name will not be used in any report. 