Secondary neutrons issue in proton radiotherapy—a brief report

Mohammad Rafiqul Islam


Secondary neutrons are unwanted byproduct in proton radiotherapy. Exposure due to secondary neutrons in proton radiotherapy could cause a significant risk for developing a secondary cancer later in the patient lifetime. The level of exposure due to secondary neutrons primarily depends on the type of beam delivery system used to deliver the primary proton dose. Although the patient body can produce significant neutrons but since these neutron are created inside the human body, their exposure is unavoidable. This report briefly discusses the type of beam delivery systems currently in use in proton radiotherapy, a relative comparison of neutron exposure in each case, and the importance of neutron study in proton radiotherapy.


Cite this article as: Islam MR. Secondary neutrons issue in proton radiotherapy-a brief report. Int J Cancer Ther Oncol 2014; 2(1):02017.



Proton therapy; Secondary neutrons; Secondary Cancer; Beam Delivery

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International Journal of Cancer Therapy and Oncology (ISSN 2330-4049)

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