作者单位:School of Medicine, University of Milan, Milan, Italy[1]Department of Radiology, European Institute of Oncology, 20141 Milan, Italy, School of Medicine[2]Department of Radiology, European Institute of Oncology, 20141 Milan, Italy[3]Department of Radiology, Vito Fazzi Hospital, Lecce, Italy[4]Division of Epidemiology and Biostatistics, European Institute of Oncology, Via Ripamonti 435[5]