1. Radiation Oncology Section, Department of Surgical and Biomedical Science, University of Perugia and Perugia General Hospital, Perugia, Italy
2. Medical Physics Unit, Perugia General Hospital, Perugia, Italy
3. Radiation Oncology Division, Perugia General Hospital, Perugia, Italy
4. Radiation Oncology Section, Department of Surgical and Biomedical Science, University of Perugia, Perugia General Hospital, Perugia, Italy