1. abcdeFrom the Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas; Department of Medical Oncology, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania; and Department of Gastroenterology, Hepatology and Nutrition, Department of Surgical Oncology, and Department of Gastrointestinal Medical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.