In a February 2020 study published in the Journal of Paediatric Oncology, the role of proton therapy in treating paediatric cancer was examined across a wide variety of cancer types. This study highlighted that with improved management of the disease, survival rates continue to improve across childhood cancer types. Reducing treatment-related long-term side effects and reducing the risk of secondary treatment-related cancers thus have become a major focus.
The use of proton radiation as medical therapy was first proposed in the 1940s, with the first treatment occurring in 1958. Since then, proton radiotherapy has undergone dramatic changes and has been increasingly sought after in childhood cancer patients with potentially-curable malignant cancers. Real gains in endocrine outcomes, neurocognitive outcomes, quality of life, and other metrics have been reported. For instance through the use of proton therapy, the radiation dose to normal healthy tissues is estimated at 60% lower than with conventional radiotherapy. Additionally, the benefits of proton radiotherapy are now being widely accepted by insurance companies and other health service providers. A survey conducted across 54 proton centres in 11 countries in 2016 estimated that between 2,000 and 2,500 child patients were treated with proton therapy in 2016, a number that has doubled since 2012.
This article highlighted the superiority of proton therapy at treating essentially every form of childhood cancer – from central nervous system cancers such as Medulloblastoma, Ependymoma, Atypical teratoid/rhabdoid tumours, Craniopharyngioma, and CNS germ cell tumours, to non-central nervous system cancers such as Rhabdomyosarcomas, Ewing’s sarcoma, Base of skull chondrosarcoma and chordoma, Hodgkin’s lymphoma, Neuroblastoma, Retinoblastoma, and Osteosarcoma.
Childhood cancers are simply better treated with protons, resulting in less impact on quality of life outcomes, developmental delays, memory impairment, clinically significant endocrinopathy, hearing difficulties, and intelligence quotient (IQ) declines. Additionally, the use of proton therapy was shown to reduce the risk of secondary cancers.
The clinical data now shows that proton radiotherapy is as effective in controlling cancer as conventional radiotherapy, and there is now increasing evidence that the toxicities of proton treatment are also lower. While randomised trials are simply ‘not possible, feasible, or even ethical’ in the United States, other methods of studying patients are being adopted through important registry work both in the United States and abroad.
Further study is essential to continue to improve outcomes in this ‘most deserving’ paediatric population. To find out if proton therapy is appropriate for you or a loved one, please contact Proton Therapy UK and the oncologists at the Prague Proton Therapy Center.
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