10 Years Dosimetric Quality Audit of Radiotherapy Centers in Iran: SSDL's On-Site Visit Program during 2007-2017

A dosimetric audit of radiotherapy centers is a quality control process that allows the accuracy of dosimetric and geometric precision of dose delivery to the patient. It can be used to evaluate the accuracy of dose delivery to the tumor during radiotherapy at various treatment centers. Differences in prescriptive dose, depending on the severity, have potential consequences not so important, severe and even fatal. Measuring the absolute output of linear accelerators (LINACs) under reference conditions is a gold standard method for verifying the accuracy of the radiotherapy dose delivery. Radiotherapy centers in Iran have been auditing by the Secondary Standard Dosimetry Laboratory (SSDL) since 1991. In this study, in accordance with TRS 398 and inspection instructions from the International Atomic Energy Agency's QUATRO Group [2], the dosimetric audit for 10 years during 2007-2017, was performed and the differences between SSDL and the inspected center were reported.