In-vivo dosimetry with EBT-3 gafchromic films and thermoluminescent dosimeters in breast cancer radiotherapy treatments

Purpose Breast cancer is the first common cancer and one of the deadliest cancers among women worldwide. The treatment of cancer patients using radiotherapy involves many risk factors which can lead to severe complications. The aim of this study was to investigate measured doses received by breast cancer patients during external beam radiotherapy (EBT) treatment and compare to doses prescribed, using EBT-3 films and TLDs as detectors. Dosimetric evaluation of entrance doses during patient irradiation and scattered doses to sensitive organs for patients requiring postmastectomy radiotherapy (PMRT) were carried-out. Method Total of 183 field measurements for left and right breasts were performed on a male and 60 females undergoing PMRT. Measurements of delivered doses to patients were performed by applying both EBT-3 film and TLD chips directly on patient skin along the central beam axis, and on the sensitive selected organs during irradiations to measure scattered radiations. Irradiated films were scanned with a flatbed scanner and analysed with ImageJ software. The TLDs were read using Hawshaw 6600 TLD reader. Result The percentage error between measured and prescribed doses ranged from 0.07%—8.76%,