Comparison of the Y-90 brachytherapy and Ir-192 brachytherapy of skin tumors: a simulation study

Abstract

Skin brachytherapy is a successful practice for treating skin cancer patients. Although a gamma source like an Iridium-192 (Ir-192) is commonly used in the skin brachytherapy, the use of a beta source like Yttrium-90 (Y-90) has also been investigated for this purpose. In the current study, we simulated the dose distribution of a proposed Y-90 applicator and an Ir-192 Leipzig applicator in a skin phantom, and compared the performance of each of the methods in treating three tumors in three hypothetical scenarios. Results of this simulation study showed that because of the sharp dose falloff of beta radiation in tissue, the Y-90 applicator may lead to better protection of the bone and/or cartilage under thin tumors. However, it may lead to excessive skin surface dose if thick skin tumors are treated. To choose between the Ir-192 and Y- 90 applicators, one may need to consider the thickness of the tumor and the thickness of the adipose layer between the tumor and the bone.

Keywords

• skin tumor
• skin brachytherapy
• y-90
• ir-192
• simulation