1. From the Radiation Oncology Center, Azienda Ospedaliera, Terni; Radiation Oncology Center, University School of Medicine, and Service of Medical Physics, Policlinico Hospital; Medical Oncology Service, Azienda Sanitaria n.2, Perugia; Radiation Oncology Center, Hospital, Arezzo; Radiation Oncology Center, Hospital, Lucca; and Radiation Oncology Center, University School of Medicine, Careggi Hospital, Firenze, Italy