Marco Chiappetta1,2,3, Mirella Marino2, Francesco Facciolo3. 1. Thoracic Surgery, Università Cattolica del Sacro Cuore - Fondazione Policlinico Universitario A. Gemelli, Rome, Italy. 2. Department of Pathology, "Regina Elena" National Cancer Institute, Rome, Italy. 3. Thoracic Surgery Unit, "Regina Elena" National Cancer Institute, Rome, Italy.