Published in the Green Journal, this survey study presented the data from 40 participating centers (participation rate: 74%), a total of 1,860 patients treated in 2016 (North America: 1205, Europe: 432, Asia: 223). More than 30 pediatric tumor types were identified, mainly treated with curative intent: 48% were CNS, 25% extra-cranial sarcomas, 7% neuroblastoma, and 5% hematopoietic tumors.

About half of the patients were treated with pencil beam scanning. Treatment patterns were broadly similar across the three continents. The authors concluded that the low numbers of patients treated in each center indicate the need for international research collaborations to assess long-term outcomes of proton therapy in pediatric patients.