The published work will help estimate doses absorbed by organs that are far from the irradiated zone in children treated with conventional radiotherapy or proton therapy


Antropomorphic phantoms used to validate computational models (adapted from De Saint-Hubert et al. 2022, Front Oncol.)

A concern in radiotherapy is the possible appearance of second cancers that are produced by the irradiation of the patient during the treatment of a primary tumour. This concern becomes even more relevant in the case of paediatric patients, since these second cancers appear usually many years after the initial treatment. Although it is well known that the dose absorbed by tissues far from the irradiated zone plays an important role in the probability of developing these tumours, there is little knowledge on how to estimate the amount and distribution of these “off-target” doses.

HARMONIC researchers recently published two papers that will greatly help to address this issue. The studies were led by Prof. Dr. Lorenzo Brualla, researcher at the West German Proton Therapy Centre at Essen and leader of the dose reconstruction task in the HARMONIC project.

In the published work, the researchers developed several computational methods in order to estimate this far-from-the-field dose, both in the case of conventional radiotherapy (ie. photon therapy) or with proton therapy. In both cases, the computational methods developed by Brualla and his team were tested and validated with experiments conducted with anthropomorphic paediatric phantoms.

The published articles are the result of the collaboration of the groups involved in the dosimetry tasks of HARMONIC, namely, the Belgian Nuclear Research Centre (SCK.CEN) led by Dr. Marijke De Saint-Hubert, the French Atomic Energy Commission (CEA) led by Dr. Guillaume Boissonnat, the University of Zürich, led by Prof. Dr. Uwe Schneider and the already mentioned West German Proton Therapy Centre Essen (WPE).

“These two articles represent the major achievements of our work package on dosimetry, up to now,” says Brualla.

The researcher also points out that the models developed for proton therapy build on previous work done by his group, and which earned PhD student Nico Verbeek a final mark of Magna cum laude for his doctoral thesis.


De Saint-Hubert M, Verbeek N, Bäumer C et al. Validation of a Monte Carlo Framework for Out-of-Field Dose Calculations in Proton Therapy. Front Oncol. 2022 Jun 8;12:882489. doi: 10.3389/fonc.2022.882489.

De Saint-Hubert M, Suesselbeck F, Vasi F, et al. Experimental Validation of an Analytical Program and a Monte Carlo Simulation for the Computation of the Far Out-of-Field Dose in External Beam Photon Therapy Applied to Pediatric Patients. Front Oncol. 2022.  Jul 7; 12:882506. doi: 10.3389/fonc.2022.882506