1. From the Departments of Radiation Oncology, Radiology, Surgery, Medicine, and Pathology, Duke University Medical Center, Durham, NC; Departments of Radiation Oncology, Radiology, Nuclear Medicine, Pathology, Hematology/Oncology, Surgery, and the Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; and the Cancer Therapy Evaluation Program, National Cancer Institute, Bethesda, MD.