Supporting safety and efficiency of advanced radiotherapy treatments

From the IAEA Division of Human Health, Dosimetry and Medical Radiation Physics Section

Joint IAEA/Argonne National Laboratory training course on small field dosimetry

Radiotherapy is an important asset in the fight against cancer. In the last decade radiotherapy technology has evolved tremendously, offering more precise and customized treatments to patients. Radiotherapy uses radiation beams that are shaped and directed toward the tumour target to eradicate the disease, while minimising their interaction with the surrounding healthy tissue, to avoid side effects.

The quality and effectiveness of the medical radiation therapy relies on its accuracy, which is ensured through the calibration of the radiation beams produced by radiotherapy machines. This is the responsibility of radiotherapy clinical medical physicists, highly qualified and trained professionals who work behind the scenes to ensure the quality of patients-related procedures. Precise measurement of the dose (or ‘dosimetry’) is crucial for this calibration and can be challenging when very small radiation beams are involved (small field dosimetry), as it is the case in some advanced radiotherapy techniques.

Experimental set-up used during the practical sessions held at the University Chicago Hospital

Techniques such as Stereotactic Radiotherapy and Intensity Modulated Radiation Therapy (IMRT) can treat very small tumours (for example inside the brain) with high precision, using small radiation beams (fields).

The IAEA is committed to support and promote safe and efficient radiotherapy for patients worldwide. Improving the accuracy of small field dosimetry in radiotherapy through the establishment of best practices has a direct impact in the increase of quality of radiotherapy treatments. For this reason, the IAEA in collaboration with the Argonne National Laboratory (ANL), U.S.A organized a training course on small field dosimetry at the University of Chicago Hospital and ANL from 10 to 14 December 2015.

The purpose of the course was to train clinical medical physicists in Member States on how to implement the new joint IAEA/American Association of Physicists in Medicine (AAPM) code of practice for the dosimetry of small static fields used in external beam radiotherapy. The course aimed at offering Medical Physicists the opportunity to learn new best practices and disseminate the knowledge to colleagues in their home countries.

The interest in the course was extremely high: 67 medical physicists submitted applications for 15 available places. This confirmed that the course responded to the needs of clinical medical physics professionals. The participants awarded were selected on the basis of the criteria outlined in the prospectus and came from 15 different IAEA Member States.

The course consisted of lectures that took place at the Argonne National Laboratory, while the entire weekend was spent on practical sessions in the radiotherapy department at the University of Chicago Hospital, which granted access to three linacs, quality assurance phantoms and provided local clinical medical physicists to assist during the weekend.

This was a unique opportunity for medical physicists from Member States to be trained on both theory and practical aspects of the new IAEA/AAPM Code of Practice for the 'Dosimetry of Small Static Fields Used in External Beam Radiotherapy'.