ESTRO 2024 Congress report

In addition to a broad coverage of dosimetry aspects for special treatment techniques such as FLASH and particle beams, a number of outstanding presentations on dosimetry of the more common photon and electron beams were delivered at this year’s ESTRO meeting.

One of them was the international comparison of radiochromic film dosimetry processes, which was presented by Andrew Alves. The process was designed to evaluate the accuracy of film absolute dosimetry regardless of the equipment used at individual centres. A pilot study was conducted that comprised eight participating centres, and Dr Alves summarised the initial results. The use of different software and scanners at the centres contributed to a large spread of results, which would have been reduced if all films had been processed at one institution that used a single scanner and piece of software.

Rushi Patel discussed the impact of dose reporting modes (dose-to-medium in medium, dose-to-water in either water or medium) for an audit of the use in the UK of stereotactic body radiotherapy on the spine. Planning system dose predictions were compared with alanine point dose measurements and, among all the participating centres, the results between the dose reporting modes differed. In another talk, Ilias Billas presented output correction factors for small field dosimetry in the magnetic field of a clinical treatment machine for different types of detectors (diamond, small ion chamber) that had been derived through Monte Carlo simulations.

Alexis Dimitriadis presented on behalf of Godfrey Azangwe on the methodological details and results of postal audits that had been performed at the International Atomic Energy Agency’s Seibersdorf laboratory. The results of the recently introduced audit of electron beams showed a larger spread than was observed for other beam types. All audits from countries that have formally recognised, clinically qualified medical physicists passed the 5% criterion. However, the spread of results from countries without recognition was much larger and a lot more failures occurred.

This brings us to the indisputable highlight – the debate on whether the need to train in dosimetry will become obsolete as artificial intelligence (AI) takes over. Although Sasa Mutic and Stephanie Tanadini-Lang provided plenty of arguments for the value of AI, Eduard Gershkevitsh and Marion Essers identified dosimetry as one of the main responsibilities of medical physics experts and specialist knowledge as essential, particularly with increasing use of AI. At the end, they secured a majority of auditorium votes (84%) in support of continued, thorough dosimetry training. Fortunately, ESTRO 2024 provided plenty of opportunities to gain such knowledge through its dosimetry-related sessions.

Sonja Wegener

Department of Radiation Oncology, University Hospital Würzburg, Germany

Wegener_S1@ukw.de