In November 2015 the so-called 4D Workshop, dedicated to planning and delivery of radiotherapy to non-static tumors, was carried out already for the seventh time. With its strong roots at the Paul-Scherrer-Institute in Switzerland and the GSI Helmholtz-Centre for Heavy Ion Research in Germany, in the last years the workshop was held at several locations around Europe. This time, about 70 participants mostly from Europe, but also from the U.S. and Japan, met for two days at OncoRay in Dresden (Germany) to discuss the cutting-edge research in topics related to radiotherapy of non-static tumors and its translation into clinical application.

While in the early years, the workshop was focused mostly on particle therapy, it is becoming more and more open also for the photon world. About one third of the participants were coming from institutions with a clinical particle therapy available and another 20% were from institution that will have a particle therapy facility in the near future. From the 31 posters about 65% were not specifically related to particle therapy. The sessions were covering a broad range of motion related topics like current clinical practice of the treatment of tumors possessing intra- and inter-fractional motion, 4D and robust treatment planning, motion monitoring and IGRT, motion modelling and deformable image registration as well as 4D in vivo dosimetry in particle therapy.

A unique feature of the workshop is its informal spirit. The number of participants is intentionally restricted with a maximum of three participants per institution. This is meant to ensure fruitful discussions and to promote new collaborations. Extended time for discussion of the invited-only oral presentations, a two and a half hour lasting poster session and the conference dinner gave numerous opportunities for vivid exchange and discussion.
A small number of industrial representatives were also invited to attend the workshop – not to contribute with an industrial exhibition but to participate in the scientific discussions. This enabled the reporting of needs of the community directly to the industry and to promote a fast clinical implementation of research results. For the 4D workshop 2016 short oral, scientific-oriented presentation of the industrial representatives are planned to close the feedback loop between research and implementation.

The location of the 2016’s edition of the workshop will be either Sapporo (Hokkaido, Japan) or Groningen (Netherlands) – to be determined in an online election of the 4D workshop community.
For more information and to be added to the 4D Workshop mailing list, please contact 4Dworkshop.aknopf@gmail.com.

2015 conference website incl. scientific program:
http://www.oncoray.de/announcements/4d-treatment-planning-workshop-2015/

Christian Richter, Kristin Stützer, Dresden
Antje-Christin Knopf, London
Christoph Bert, Erlangen