The head & neck and skin GEC-ESTRO working group consists of a core group of 23 members from several European and Asian countries. The group is currently undertaking a range of research, clinical practice and education projects. To maximise efficiency two specific task groups (eye, led by Luca Tagliaferri and skin, led by Jose Luis Guinot) were created as part of the working group.

The main aims of the working group are to propose and organise research projects for the creation of clinical evidence and to improve the quality of patient treatments by defining uniform protocols, especially in the fields of implant and quality assurance (QA) procedures, image-guided radiotherapy, 3D treatment planning, dose prescription, and dose constraints for organ at risk evaluation.

Research projects

The working group’s main research project is COBRA (Consortium for BRachytherapy data Analysis). The COBRA consortium is an international research network for interdisciplinary standardised data collection in the field of head and neck, skin and eye brachytherapy, made up of 15 international institutions. It uses a dedicated web-based platform to share clinical data, which can be used for both retrospective studies and prospective research trials.

The COBRA-Storage System (C-SS) guarantees patient privacy and is efficient to use. Thanks to its use of ‘brokers’, data can be extracted directly from a single centre's storage systems through a connection with a ‘structured query language database’. The C-SS also benefits from ‘distributed learning’ approaches, in which data never leave the collecting institution, while learning algorithms and proposed predictive models are commonly shared.

All projects start with the creation of a site-specific ontology (advanced data-set) that is used by all participants. The objectives of the project are to facilitate the management of prospective trials, and to create predictive clinical models for supporting physicians in their clinical practice by evaluating the response and the toxicity probability of a given treatment. There are several COBRA projects underway, the main ones being retrospective studies on nose and oropharynx cancer treatments and a prospective trial on skin basal cell carcinoma. All interested international groups with large mono-institutional retrospective databases are invited to join these projects.

The infrastructure SKIN-COBRA and the Consortium has received non-exclusive support from Varian Medical Systems.

Clinical practice activities

In order to homogenise clinical practice, several members are involved in writing relevant chapters of the second edition of the GECESTRO Handbook of Brachytherapy and the site-specific GEC-ESTRO/ACROP recommendation papers. In recent years, two endorsed guidelines for head and neck, and skin have been published in Radiotherapy & Oncology: in 2017 the first update of head and neck brachytherapy in squamous cell carcinomas recommendation, and in 2018 the skin brachytherapy guidelines, with a focus on 3D imaging-based treatment planning and stepping source technology.

In relation to clinical practice activities, the ‘How to treat’ project started recently. This has entailed the production of several practical teaching videos accompanied by documents for the various cutaneous or head and neck sites, useful for those who want to improve their clinical practice by observing the procedures performed and commented on by experienced members of the working group. The main objectives are: to provide tips and suggestions for troubleshooting solutions in the implant procedure; to create a common language for dose prescription; to advise on adequate methods for personalised dose distribution and organs at risk (OaR) evaluation; and to identify EQD2 minimal dose values to the target and EQD2 constraints for the OaR.

Educational activities

The working group is committed to educational issues, and many of its members are involved in several international teaching activities. The most important in this field are the ESTRO course on ‘Multidisciplinary management of non-melanoma skin cancer’ and the GECESTRO-endorsed multidisciplinary course on head and neck. In addition, in cooperation with national societies, several group members are regularly participating in different onsite educational events. In order to facilitate the educational activities in head and neck brachytherapy, especially for young physicians, the group recently approved a postgraduate residents exchange project among member institutions. Several working group members also presented on brachytherapy topics at ESTRO 37 in Barcelona and at the first ‘ESTRO meets Asia’ conference in Singapore.

The working group was well represented at the recent GEC-ESTRO workshop in Brussels, with members discussing some of the state-of-the-art developments in ongoing and future working group projects.

References

• GEC-ESTRO ACROP recommendations for head & neck brachytherapy in squamous cell carcinomas: 1st update – Improvement by cross sectional imaging based treatment planning and stepping source technology. Kovács G, Martinez-Monge R, Budrukkar A, Guinot JL, Johansson B, Strnad V, Skowronek J, Rovirosa A, Siebert FA; GEC- ESTRO Head & Neck Working Group. Radiother Oncol. 2017
• GEC-ESTRO ACROP recommendations in skin brachytherapy. Guinot JL, Rembielak A, Perez-Calatayud J, Rodríguez-Villalba S, Skowronek J, Tagliaferri L, Guix B, Gonzalez-Perez V, Valentini V, Kovacs G; GEC ESTRO. Radiother Oncol. 2018 
• ENT COBRA (Consortium for Brachytherapy Data Analysis): interdisciplinary standardized data collection system for head and neck patients treated with interventional radiotherapy (brachytherapy). Tagliaferri L, Kovács G, Autorino R, Budrukkar A, Guinot JL, Hildebrand G, Johansson B, Monge RM, Meyer JE, Niehoff P, Rovirosa A, Takàcsi-Nagy Z, Dinapoli N, Lanzotti V, Damiani A, Soror T, Valentini V., J Contemp Brachytherapy. 2016
• ENT COBRA ONTOLOGY: the covariates classification system proposed by the Head & Neck and Skin GEC- ESTRO Working Group for interdisciplinary standardized data collection in head and neck patient cohorts treated with interventional radiotherapy (brachytherapy). Tagliaferri L, Budrukkar A, Lenkowicz J, Cambeiro M, Bussu F, Guinot JL, Hildebrandt G, Johansson B, Meyer JE, Niehoff P, Rovirosa A, Takácsi-Nagy Z, Boldrini L, Dinapoli N, Lanzotti V, Damiani A, Gatta R, Fionda B, Lancellotta V, Soror T, Monge RM, Valentini V, Kovács G., J Contemp Brachytherapy. 2018