[1] Department of Radiology, Hospital Clínico Universitario de Santiago de Compostela, Choupana s/n, Santiago de Compostela
[2] Paul Strickland Scanner Centre, Mount Vernon Cancer Centre, Northwood, Middlesex
[3] Department of Radiology, IVO (Instituto Valenciano de Oncología), C/ Beltrán Báguena, 8, Valencia
[4] Department of Radiology, Advanced Medical Imaging, Clinica Las Nieves, SERCOSA, Grupo Health Time, C/ Carmelo Torres 2, Jaén
[5] Case Western Reserve University, Cleveland, OH
[6] Department of Radiotherapy, Hospital Clínico Universitario de Santiago de Compostela, Choupana s/n, Santiago de Compostela
[7] Department of Gastroenterology, Colorectal Cancer Group, Hospital Clínico Universitario de Santiago de Compostela, Choupana s/n, Santiago de Compostela