1. Department of Pathological Anatomy, University of Bari, Bari
2. Department of Dental Sciences and Surgery, University of Bari, Bari
3. Department of Experimental Oncology, European Institute of Oncology and University of Milan, Milan
4. Department of Epidemiology and Biostatistics, European Institute of Oncology, Milan
5. FIRC Institute for Molecular Oncology (IFOM), Milan
6. Division of Head and Neck Surgery, University of Chieti, Chieti
7. Division of Pathology and Laboratory Medicine, European Institute of Oncology and University of Milan, Milan, Italy