Material and methods:
Allpatientsyounger than 25years,consecutively treated with PBTbased on a multi-disciplinary tumor board decision were analyzed. Patients were treated under daily on-board kilovoltage x-ray and/or cone beam CT scan guidance. The demographic profile, treatment characteristics and the acute toxicities were reported. Patient and treatment related factors and their association with acute toxicities were analyzed using univariate and multivariate analysis.