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Samarium-145: a new brachytherapy source.

R G Fairchild·J Kalef-Ezra·S Packer·L Wielopolski·B H Laster·J S Robertson·L Mausner·C Kanellitsas
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Abstract

A new radiation source has been produced for brachytherapy, with radiation energies slightly above those of 125I, and a T1/2 of 340 d. This source, 145Sm, is produced by neutron irradiation of 144Sm (96.5% enriched). Decay is by electron capture with 140 K x-rays per 100 disintegrations in the energy region between 38-45 keV, plus 13 gamma-rays at 61 keV. These sources are encapsulated in Ti tubes, approximately 0.8 mm X 4.5 mm, and have been developed for temporary implantation in brain and ocular tumours. The 38-61 keV photons should make such sources easy to shield, while providing a dose distribution from source arrays somewhat more homogeneous than that from 125I. In addition, the 340 d half life of 145Sm permits its use for times significantly longer than that of 60 d 125I. While the 145Sm sources have been designed primarily for implantation in a brain tumour, they should be useful for almost any conventional brachytherapy application.

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BrachytherapyBrain NeoplasmsEye NeoplasmsHumansModels, TheoreticalRadioisotopesRadiotherapy DosageSamariumJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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R G Fairchild, J Kalef-Ezra, S Packer, L Wielopolski, B H Laster, J S Robertson, L Mausner, C Kanellitsas. 1987. Samarium-145: a new brachytherapy source.. https://doi.org/10.1088/0031-9155%2F32%2F7%2F005

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