Validation of an Individualized Home-Made Superficial Brachytherapy Mould Applied for Non-Melanoma Skin Cancer

Abstract

Purpose: This study was conducted to evaluate the effect of a Brachytherapy (BT) customized mold (Condensation silicone elastomer (Protesil TM )) thickness ,on dose distribution pattern in deeper lesions used for nonmelanoma skin cancers (NMSC).Material and Method: MOSFET TM and GAFCHROMIC TM EBT3 film dosimeters were used for the different thicknesses of a Brachytherapy (BT) customized mold (up to 20 mm), skin dose and dose in different depths were evaluated.Result: The received dose to the surface is overestimated by TPS.Skin dose can be reduced from 250 to 150% of prescription dose by increasing mold thickness from 5 mm to 20 mm. There was a 7.7% difference in calculated dose by TPS and measured dose by MOSFET. Film dosimetry data was unreliable. There was a good agreement between film dosimetry, MOSFET detector, and TPS results, in the depth of 5mm<.Conclusion: Any individualized material chosen to use for making the customized surface BT mold should be validated at BT departments. Protesil TM can be selected as feasible material to make any form of superficial molds. For thicker NMSC lesions up to 20 mm using thicker molds up to 20 mm can be. Even for 10 mm lesions, by changing mold thickness from 5 mm to 20 mm, skin dose would reduce. Protesil TM can be used to make an individualized superficial BT mold. By increasing the mold thickness, lesions can be treated without overexposing the skin surface and skin dose reduced by increasing mold thickness. So, superficial BT can be recommended as an appropriate treatment option for NMSC lesions with some consideration.