ESTRO 36 Abstract Book

S98 ESTRO 36 2017 _______________________________________________________________________________________________

With the development of advanced radiotherapy technologies resulting in greater complexity of radiation treatments, it was necessary to extend basic dosimetry audits. More complex audit programmes involve tests of different beam parameters, machine performance characteristics and treatment delivery techniques. Examples include audits of small beam dosimetry, complex irradiations, combined beams, audits of treatment planning, and ‘end-to-end’ methodologies. Although the accurate clinical dosimetry is essential for the effective radiation treatment, the desired patient outcome cannot be achieved without the adequate quality of clinical, physical and technical processes. A comprehensive IAEA audit methodology called the Quality Assurance Team for Radiation Oncology (QUATRO) was developed to review the entire radiotherapy chain and infrastructure. Since 2005 QUATRO audits have been conducted in approximately 90 radiotherapy centres in various world regions. The experiences above demonstrate that quality audits improve dosimetry and clinical practices. Audits have been effective in identifying discrepancies in dosimetry and in providing support to participating centres in resolving them. Audits can lessen the likelihood of major dosimetry errors and the resulting consequences for patient outcomes. Audits also address smaller errors and help in reducing uncertainties in the dose delivery thus improving the treatment quality for many patients. Audits can provide support and confidence when introducing new technologies and complex processes in radiotherapy. Audits verify the consistency of dosimetry practices among centres in different countries and world regions. They strengthen the confidence in clinical dosimetry both for physicists and clinicians who obtain assurance that their patients are given accurate doses in accordance with medical prescription. The significance of quality audits in radiotherapy and their impact on dosimetry and clinical practices have been widely recognized. Still, a large number of radiotherapy centres do not participate in such audit programmes. Due to obvious benefits, all centres should be encouraged to take part in quality audits in radiotherapy.