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Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

ABSTRACT: PURPOSE:This work proposes a theoretical framework that enables comparative risk predictions for second cancer incidence after particle beam therapy for different ion species for individual patients, accounting for differences in relative biological effectiveness (RBE) for the competing processes of tumor initiation and cell inactivation. Our working hypothesis was that use of carbon-ion therapy instead of proton therapy would show a difference in the predicted risk of second cancer incidence in the breast for a sample of Hodgkin lymphoma (HL) patients. METHODS AND MATERIALS:We generated biologic treatment plans and calculated relative predicted risks of second cancer in the breast by using two proposed methods: a full model derived from the linear quadratic model and a simpler linear-no-threshold model. RESULTS:For our reference calculation, we found the predicted risk of breast cancer incidence for carbon-ion plans-to-proton plan ratio, , to be 0.75 ± 0.07 but not significantly smaller than 1 (P=.180). CONCLUSIONS:Our findings suggest that second cancer risks are, on average, comparable between proton therapy and carbon-ion therapy.

SUBMITTER: Eley JG

PROVIDER: S-EPMC4844193 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

Eley John G JG Friedrich Thomas T Homann Kenneth L KL Howell Rebecca M RM Scholz Michael M Durante Marco M Newhauser Wayne D WD

International journal of radiation oncology, biology, physics 20160216 1

<h4>Purpose</h4>This work proposes a theoretical framework that enables comparative risk predictions for second cancer incidence after particle beam therapy for different ion species for individual patients, accounting for differences in relative biological effectiveness (RBE) for the competing processes of tumor initiation and cell inactivation. Our working hypothesis was that use of carbon-ion therapy instead of proton therapy would show a difference in the predicted risk of second cancer inci ...[more]

PMID: 27084647

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Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

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Comparative Risk Predictions of Second Cancers After Carbon-Ion Therapy Versus Proton Therapy.

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