DEVELOPING AND IMPLEMENTING THE QUALITY CONTROL PROGRAM ON A LINEAR ACCELERATOR

Abstract

Relevance: The article deals with modern problems in the field of ensuring the quality of services provided on linear accelerators from the point of view of the regulatory framework, as well as from the point of view of the frequency of control procedures. The scientific novelty lies in elaborating a linear accelerator quality control program with detailed procedure descriptions and testing frequency recommendations. The study aimed to – develop and test a set of simple methods for controlling the linear accelerator’s mechanical and dosimetric parameters, which would meet the minimum requirements for high-tech radiation therapy following IAEA and AAPM international recommendations. Methods: In developing the quality control program for the TrueBeamSTx linear accelerator (Varian, USA) installed at the Almaty Oncological Center (AOC, Kazakhstan), we relied on the recommendations of the International Atomic Energy Agency (IAEA) and the American Association of Physicists in Medicine (AAPM), taking into account that intensity-modulated radiotherapy (IMRT, VMAT), stereotactic radiosurgery and stereotactic radiotherapy (SRS, SRT), using image-guided radiation therapy (IGRT) will be performed on the accelerator, which imposes more stringent requirements for control of both mechanical and dosimetry characteristics Results: Over three years of operation, the TrueBeamSTx accelerator shows good stability of mechanical and dosimetric characteristics, verified using systematic tests according to the quality control program developed by the authors of this article. The IAEA/WHO mail dose monitoring program using radiophotoluminescent detectors, implemented in 2019-2022, showed high dosimetric measurements and calculations accuracy of 0.1-1.7%, at a tolerance of 5%. Conclusion: A quality control program for a high-energy linear accelerator has been developed; the results obtained for all characteristics correspond to the permissible values. The effective and safe use of radiotherapy requires the development of a quality control program for all radiotherapy equipment specifically for each institution and independent verification of the implementation of this program.