放射治療仍然是多科團隊治療小兒實體癌症的主要利器。但是，傳統光子放射治療可能會導致晚期併發症和次發性癌症發生。考慮到質子束治療(proton beam radiotherapy)具有允許對腫瘤進行消融放射劑量，並同時減少鄰近器官之放射劑量的優點，質子治療在小兒癌症患者已成為新興的治療角色。在本文中，我們簡要回顧小兒癌症病人、包括髓母細胞瘤，顱内生殖細胞瘤，低惡性度神經膠質瘤，何杰金氏淋巴瘤，神經母細胞瘤或軟組織肉瘤，接受質子治療後之臨床預後、治療副作用、次發性癌症風險和生活品質狀況。儘管缺乏比較質子治療和光子放射治療之療效和毒性的隨機臨床試驗，但當前數據仍支持質子治療來治療小兒癌症，其最主要原因是令人鼓舞的治療成果。質子治療不僅提供更好的腫瘤局部控制，更少的急性和晚期不良反應，較少罹患次發性癌症風險以及更高的生活品質。

Radiotherapy remains the main treatment multimodalities for pediatric solid cancers. However, conventional photon radiotherapy may result in late complications and occurrence of second cancers. Considering that proton beam therapy (PBT) possesses advantages of allowing ablative radiation dose to tumors and simultaneously sparing radiation dose to neighboring organs, the PBT becomes the emerged role in the treatment of pediatric cancer patients. In this article, we briefly reviewed the clinical outcome, toxicities, quality of life, and secondary cancer risk in pediatric cancer patients with medulloblastoma, intracranial germinoma, low-grade glioma, Hodgkin’s lymphoma, neuroblastoma, or soft tissue sarcoma who received PBT as the modality therapy. Although the lack of randomized trials comparing the efficacies and toxicities between PBT and photon radiotherapy, the current data supported that PBT in treating pediatric cancer patients is encouraging because PBT not only provides better tumor local controls and less acute and late adverse effects but also affords less risks of second cancer, and better qualities of life.