Guide for quality control and safety of external radiotherapy treatment planning systems and treatment plans

To present a guideline for quality control of the external radiotherapy treatment planning system (TPS) and treatment plans from the Spanish Society of Medical Physics. The document provides recommendations for each part of the process, from commissioning and periodic checks of the TPS to treatment planning processes and plan verifications.

The minimum necessary equipment required to carry out the recommended tasks is described. Subsequently, recommendations for the characterization and modelling of treatment units are presented, divided into beam data acquisition, configuration, and validation. Next, the document focuses on quality control of the TPS, outlining recommendations regarding the initial reference state, periodic checks, and software updates. This is followed by quality assurance of the treatment planning process, structured into three subsections: implementation of new techniques (end-to-end tests and audits), evaluation of treatment plans, and protocolization and class solutions. The final section contains recommendations about treatment plan verification, covering the commissioning and quality control of dedicated systems, as well as their recommended usage and the organization of treatment verifications. The document concludes with a table listing explicit tolerances for each process.

This guideline offers a novel framework for harmonizing the quality of radiotherapy treatment planning, with emphasis on end-to-end evaluations, modeling accuracy, process verification, and periodic stability assessments. These recommendations provide a clear direction for harmonizing current practices and are expected to enhance the reliability and safety of TPS calculations by reducing variability and promoting consistency and efficiency in treatment planning processes.