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Monte Carlo investigation of the characteristics of radioactive beams for heavy ion therapy.

ABSTRACT: This work presents a simulation study evaluating relative biological effectiveness at 10% survival fraction (RBE10) of several different positron-emitting radionuclides in heavy ion treatment systems, and comparing these to the RBE10s of their non-radioactive counterparts. RBE10 is evaluated as a function of depth for three positron-emitting radioactive ion beams (¹⁰C, ¹¹C and ¹⁵O) and two stable ion beams (¹²C and ¹⁶O) using the modified microdosimetric kinetic model (MKM) in a heterogeneous skull phantom subject to a rectangular 50?mm?×?50?mm?×?60?mm spread out Bragg peak. We demonstrate that the RBE10 of the positron-emitting radioactive beams is almost identical to the corresponding stable isotopes. The potential improvement in PET quality assurance image quality which is obtained when using radioactive beams is evaluated by comparing the signal to background ratios of positron annihilations at different intra- and post-irradiation time points. Finally, the incidental dose to the patient resulting from the use of radioactive beams is also quantified and shown to be negligible.

SUBMITTER: Chacon A

PROVIDER: S-EPMC6484004 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Monte Carlo investigation of the characteristics of radioactive beams for heavy ion therapy.

Chacon Andrew A Safavi-Naeini Mitra M Bolst David D Guatelli Susanna S Franklin Daniel R DR Iwao Yuma Y Akamatsu Go G Tashima Hideaki H Yoshida Eiji E Nishikido Fumihiko F Kitagawa Atsushi A Mohammadi Akram A Gregoire Marie-Claude MC Yamaya Taiga T Rosenfeld Anatoly B AB

Scientific reports 20190425 1

This work presents a simulation study evaluating relative biological effectiveness at 10% survival fraction (RBE10) of several different positron-emitting radionuclides in heavy ion treatment systems, and comparing these to the RBE10s of their non-radioactive counterparts. RBE10 is evaluated as a function of depth for three positron-emitting radioactive ion beams (10C, 11C and 15O) and two stable ion beams (12C and 16O) using the modified mi ...[more]

PMID: 31024057

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Monte Carlo investigation of the characteristics of radioactive beams for heavy ion therapy.

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Monte Carlo investigation of the characteristics of radioactive beams for heavy ion therapy.

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