1. Department of Surgical Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
2. Department of Colon and Rectal Surgery, University of Texas MD Anderson Cancer Center , Houston, Texas, USA
3. Department of Radiology, University of Texas MD Anderson Cancer Center , Houston, Texas, USA
4. Department of Pathology, University of Texas MD Anderson Cancer Center , Houston, Texas, USA
5. Department of Gastrointestinal Medical Oncology, University of Texas MD Anderson Cancer Center , Houston, Texas, USA