In General

Proton therapy, or proton beam therapy, is a type of radiation therapy used in the treatment of cancer. Unlike photon-based forms of external beam radiotherapy, proton therapy enables an intense dose distribution pattern, depositing radiation in the precise dimensions of a tumor while eliminating the exit dose and damage to adjacent normal tissue.

proton beam no exit doseSparing normal tissue and improving quality of life is important for all patients. But because of the long natural life expectancy of pediatric patients — and the particularly radiosensitive nature of developing tissue — pediatric oncologists place heightened emphasis on late effects.

Childhood cancer survivors often overcome one enormous battle only to encounter another, months, years, or even decades after treatment has ended. Cosmetic, hormonal, neurocognitive, reproductive, and other physical impairments are prevalent among survivors. This is particularly true for pediatric patients whose disease sites occur near the brain stem, spinal cord, and other sensitive organs.

Of utmost concern are radiation-induced secondary cancers. The relationship between radiation therapy and secondary cancers has been clarified. For example, the Childhood Cancer Survivor Study[1] has assessed more than 14,000 childhood cancer survivors to determine how different treatment plans have affected their long-term health. This data demonstrates a correlation between radiotherapy and various secondary malignancies, including, but not limited to:

  • Basal cell carcinoma[2]
  • Breast cancer[3]
  • Gastrointestinal cancer[4]
  • Meningioma[5]
  • Salivary gland cancer[6]
  • Thyroid cancer[7]

A growing body of research suggests that proton therapy may spare pediatric patients from developmental, cognitive, and other complications associated with photon-based forms of external beam radiotherapy. This is especially promising for the prevention of secondary malignancies.

Learn more about treating pediatric cancers with proton therapy. Download our free white paper.

pediatrics and proton therapy


[1] St. Jude Children’s Research Hospital. Childhood Cancer Survivor Study. Accessed August 2018.

[2] T.C. Watt, P.D. Inskip, K. Stratton, et. al. Radiation-related risk of basal cell carcinoma: a report from the Childhood Cancer Survivor Study. J Natl Cancer Inst. 104(16):1240-50 (2012). doi: 10.1093/jnci/djs298

[3] C.S. Moskowitz, J.F. Chou, S.L. Wolden, et. al. Breast cancer after chest radiation therapy for childhood cancer. J Clin Oncol. 20;32(21):2217-23 (2014). doi: 10.1200/JCO.2013.54.4601

[4] T.O. Henderson, K.C. Oeffinger, J. Whitton, et. al. Secondary gastrointestinal cancer in childhood cancer survivors: a cohort study. Ann Intern Med. 5;156(11):757-66, W-260 (2012). doi: 10.1093/jnci/djs298

[5] D.C. Bowers, C.S. Moskowitz, J.F. Chou. Morbidity and Mortality Associated With Meningioma After Cranial Radiotherapy: A Report From the Childhood Cancer Survivor Study. J Clin Oncol.  10;35(14):1570-1576 (2017). doi: 10.1200/JCO.2016.70.1896.

[6] H. Boukheris, M. Stovall, E. Gilbert, et. al. Risk of salivary gland cancer after childhood cancer: a report from the Childhood Cancer Survivor Study. Int J Radiat Oncol Biol Phys. 1;85(3):776-83 (2013). doi: 10.1016/j.ijrobp.2012.06.006

[7] H. Lene, S. Veiga, E. Holmberg, et. al. Thyroid Cancer after Childhood Exposure to External Radiation: An Updated Pooled Analysis of 12 Studies. Radiation Research 185(5):473-484 (2016). doi: 10.1667/RR14213.1