1. Division of Thoracic Surgery, IEO, European Institute of Oncology IRCCS, Via Ripamonti, 435, 20141 Milan, Italy
2. Division of Epidemiology and Biostatistics, IEO, European Institute of Oncology IRCCS, 20141 Milan, Italy
3. Department of Oncology and Haemato-Oncology, University of Milan, 20141 Milan, Italy