1. Radiation Therapy Unit, Department of Oncology and Hematology, University Hospital of Modena, 41124 Modena, Italy
2. Medical Oncology Unit, University Hospital of Parma, 43126 Parma, Italy
3. Proton Therapy Unit, APSS Trento and CISMed, University of Trento, 38100 Trento, Italy
4. Medical Oncology Unit, University Hospital of Parma, 43126 Parma, Italy; Department of Medicine and Surgery, University Hospital of Parma, 43126 Parma, Italy