بررسی اثر بیس پلیت غیر فیبر کربنی بر دز پوست در پرتودرمانی سرطان پستان با استفاده از فیلم گاف‌کرومیک EBT2

Background and purpose: Due to creation of scattered radiation when using non-carbon fiber base plates particularly in treating breast cancer, applying this device can affect skin and body surface dose. Recently, using Gaf-Chromic films have led to obtaining good results in skin dosimetry. The purpose of this study was the estimation of skin dose in applying non-carbon fiber base plates using water phantom and Gaf-chromic films. Materials and methods: In an experimental study, calibration curves in 6 and 15 MV photon mode of operation of a Siemens Primus were derived for the EB2 Gaf-Chromic films. To obtain these curves parallel plate Roos dosimeter was utilized. To measure the effect of non-carbon fiber base plate, films were attached to the bottom of a 30×30×30 cm3 water phantom and were exposed in two different energies with and without placing the non-carbon fiber base plate on the Linac coach. Results: Calibration curves for both energies were fairly correlated to linear functions. Percentage difference for the mentioned situations (with and without using base plate) for 6 and 15 MV energies were 16.56% and 5.27%, respectively. Conclusion: In breast cancer radiation therapy, applying non-carbon fiber base plate, can increase the skin dose in posterior supraclavicular field. In this study the increase was more pronounced in 6 MV energy than 15 MV.