Radiation treatment is an important treatment modality for the majority of the cancer patients, leading to good rates of local control and overall survival. Its success also indicates it for the treatment of recurrences or second primary tumours in long term cancer survivors. These secondary targets may overlap, fully or partially, with the primary target, meaning that the patient is at risk of receiving a second and sometimes even a third radio-oncological treatment in the same region, a situation being described as re-irradiation. A broad array of treatment techniques and equipment is nowadays available to deliver complex dose distributions in case of re-irradiation. Nevertheless, the decision to deliver radiation therapy in case of re-irradiation requires a careful consideration of the implications for tissue complications and achievable tumour control. Major challenges are uncertainties about the knowledge of the tolerance of normal tissues and the mechanisms dealing with the repair of damage from previous irradiations, the influence of comorbidities and other factors.

This workshop aims to review the present day knowledge on re-irradiations from a multidisciplinary perspective. It will address the main pillars on which the re-irradiation is performed: Radiobiology (reviewing the experimental investigation of the radiobiological mechanisms of normal tissue tolerance and their translation to the clinic), Physics (reviewing the techniques for image guidance and radiation delivery) and Clinic (reviewing the present experience from re-irradiation). Each of these will have dedicated sessions complemented by discussion sessions merging the different perspectives.

We hope that this workshop will continue in the spirit of our previous workshops (2014 - New school versus old school radiobiology and 2016 - The risk of second cancer from therapeutic irradiations) and generate new ideas that will ultimately improve the management of patients in need of re-irradiation.

Organisers (alphabetical):

Andrzej Wojcik - Centre for Radiation Protection Research, Stockholm University

Iuliana Toma-Dasu - Medical Radiation Physics, Stockholm University and Karolinska Institutet

Lovisa Lundholm - Centre for Radiation Protection Research, Stockholm University

Mattias Hedman - Karolinska University Hospital

Invited speakers (alphabetical):

Albert van der Kogel – University of Wisconsin, USA

Alexandru Dasu – The Skandion Clinic, Sweden

Bleddyn Jones – Oxford Institute for Radiation Oncology, UK

Caroline Chung – MD Anderson Cancer Center, USA

Carsten Nieder - The Arctic University of Norway, Tromsø

Claes Mercke – Karolinska University Hospital, Sweden

David Schlesinger – University of Virginia Health System, USA

Dorota Gabrys – Maria Sklodowska Curie Memorial Cancer Centre, Gliwice, Poland

Judith van Loon – MAASTRO Clinic, Netherlands

Klaus Trott – University College London and Technical University of Munich

Martin Fast – The Netherlands Cancer Institute, Netherlands

Michael Gubanski – Karolinska University Hospital, Sweden

Nobuyuki Kanematsu – National Institute of Radiological Sciences, Japan

Ricardo Palanco-Zamora – Karolinska University Hospital, Sweden

Rob Coppes – University of Groningen, Netherlands

Stephanie Combs – Technical University of Munich, Germany