[1] Natl Ctr Oncol Hadrontherapy CNAO, Clin Dept, Radiat Oncol Unit, I-27100 Pavia, Italy
[2] Natl Ctr Oncol Hadrontherapy CNAO, Clin Dept, Med Phys Unit, I-27100 Pavia, Italy
[3] Univ Pavia, Dept Clin Surg Diagnost & Pediat Sci, I-27100 Pavia, Italy