WP4 - TG43 

Chair: Facundo Ballester and José Perz-Calatyaud

The TG43 data of "conventional" brachytherapy sources -mainly 137Cs and 192Ir sources- are collected by the group at the University of Valencia. New sources or new source data can be added. Data are also included on low-energy photon emitting brachytherapy sources (125I, 103Pd) that comply with the prerequisites of AAPM TG-43. If consensus datatsets coud be obtained by the AAPM, these are included on the Estro web page. The contents are supervised by a BRAPHYQS expert team. A new entrance to the Braphyqs website data can be accessed. The BRAPHYQS group has written a short introductory text to the TG-43 data site with explanation on use and background information. Research data -which means: non-validated sets of TG43 data- will stay available using the 2nd website still located at the University of Valencia: http://www.uv.es/braphyqs. Transfer of the data from the http://www.uv.es/braphyqs site to this site has been done. 

Some members of BRAPHYQS group are also members of the AAPM Brachytherapy Subcommittee (BTSC) and its working groups. In these positions, they represent the ESTRO community, reflected in an ESTRO’s co-sponsorship of the reports “Dosimetric prerequisites for routine clinical use of photon emitting brachytherapy sources with average energy higher than 50 keV” by Zuofeng Li et al., Med Phys. Dec 2007; 34:37-40) and “Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: Report of the AAPM and ESTRO” by Perez-Calatayud et al. Med. Phys. 39 (5), May 2012.

The coordination between BRAPHYQS group and the BTSC Subcommittee lead to a full consensus on the data of the Low-Energy as well High Energy Brachytherapy Dosimetry data, with an Internet presentation of such data using links from the ESTRO site to USA counterparts and vice versa.

WP5 - Calibration Facility for 125I

Chair: Frank-André Siebert

Calibration facilities for 125I and 103Pd sources with easy access for European institutes are lacking. Actually, in the world only NIST provides the user with a calibration facility and recently PTB Braunschweig (H.J. Selbach) has opened a WAFAC type 125I calibration facility. The purpose of the taskgroup is to further stimulate European primary and secondary standard labs in co-operation within EUROMET to develop such standards for these low-energy sources. Following a previous contact with PTB by Alex Rijnders, Jack Venselaar and Tony Aalbers (NMi NL), a small mini-symposium in parallel to the ESTRO 25 meeting in Leipzig (Oct 2006) was organized. Invitations were sent to representatives of different EU and USA labs and ABS (on behalf of BRAPHYQS, Jack Venselaar, Alex Rijnders, Heikki Toelli, Taran Paulsen Hellebust and José Pérez-Calatayud ). The meeting was successful and it was agreed that there is a need for cooperation between labs and “customers”. Several ideas were discussed and will be brought to the attention of the board of EURAMET. The EURAMET project T2.J06 is a project of European standard laboratories with the goal to establish dose-to-water calibration in brachytherapy. BRAPHYQS is cooperating with the EURAMET T2.J03 project group, offering the expertise of BRAPHYQS to this project. As chair of BRAPHYQS F.-A. Siebert is invited to the EURAMET meetings.

WP14: in vivo dosimetry

Chair: Kari Tanderup

In vivo dosimetry for brachytherapy is rarely used routinely in clinical practice today. The reason is the lack of dosimetry systems with a high enough accuracy to identify and prevent errors in treatment delivery. Currently, the benefit of using in vivo dosimetry is therefore very limited and many clinics are not performing it. The aim of WP14 is to advance the field in order to make in vivo a routine part of brachytherapy. Significant advances have been seen the last years in terms of developments of new dosimeter systems based on either point dosimeters or flat panels. Systems are now becoming available in research settings, which can provide information with such high precision that it becomes clinically relevant.

Furthermore, surveys have been sent to clinics to obtain information about the need and request for in vivo dosimetry, and to get insight into the type of incidences which an in vivo dosimetry system should be able to detect. Currently, a large survey on treatment verification is being prepared with the aim at distributing it to clinics across Europe in the summer of 2018. Furthermore, an ESTRO task group is working on a “White Paper” on the current status of in vivo dosimetry and requirements needed before in vivo dosimetry can be a part of the daily clinical brachytherapy practice - both for brachytherapy and external beam radiotherapy.  This paper will be written before end of 2019.

WP17 - Dicon standard in brachytherapy

Chair: Yury Niatsetki 

The goal of the WP 17 DICOM Standard in Brachytherapy is to improve interconnectivity between different planning systems in brachytherapy, facilitating plan comparison for clinical studies:

1)      Evaluation of dose distributions used for treatment

2)      Exchange of treatment plans between TPS of different vendors

3)      Compare 3D treatment planning dose calculations

These are not fully covered in the currently used 1st generation DICOM RT objects because the those were developed more than 20 years ago.

BRAPHYQS group is one of the stakeholders of the DICOM WG-07 Brachytherapy Subgroup, working on 2nd generation DICOM RT objects and on the IHE-RO (Integrating the Healthcare Enterprise – Radiation Oncology) Brachytherapy Workflow profile, addressing solutions for interconnectivity issues using the DICOM objects provided in its 1st generation.

WP19: Quality Control of Brachytherapy Treatment Planning Systems

Chair: Marisol De Brabandere and Alex Rijnders

Currently there are no dedicated, practical reports available on commissioning and quality assurance (QA) of treatment planning systems (TPS) for brachytherapy. Most of the existing reports and handbooks on TPS commissioning are either too concise or too theoretical, or are focusing on external beam therapy only. The aim of the WP19 project is

1)       to provide users with guidelines for commissioning and quality assurance (QA) of brachytherapy treatment planning systems at the time of implementation and after minor and major software upgrades/updates; 

2)       to provide a set of practical tools (spreadsheets, DICOM sets, checklists, …) to validate the TPS calculation accuracy and performance.

Unlike other work packages within BRAPHYQS, WP19 is an open project with support of non-BRAPHYQS members. An appeal for contributors was made in 2017, resulting in a group of brachytherapy physicists from all over Europe. Representatives from the American Association of Physicists in Medicine (AAPM) and Australasian Brachytherapy Group (ABG) are included. In spring 2018 an application for ACROP approval was submitted to ESTRO.

Five main subtopics have been defined for this report: (a) geometry and imaging, (b) source and afterloader specification, (c) dose calculation accuracy and representation, (d) (library) applicator specifications and (e) output/data transfer and reporting. For each topic a coordinator and several contributors were assigned. The guidelines will handle both HDR/PDR/LDR and seed implant brachytherapy. It will focus on TG43-based algorithms only, as an AAPM working group is currently preparing a separate report on advanced MC-based dose calculation algorithms. Commissioning and quality control of image fusion will not be discussed in detail because of a Braphyqs review being prepared simultaneously on this topic. Commissioning of applicator reconstruction will be handled briefly, as in 2007 GEC-ESTRO recommendations were already published on applicator commissioning with detailed guidelines and examples. Eye plaque calculation and iridium-192 wire calculation are both excluded from the WP19 project.  

WP20 Image Matching in Brachytherapy

Chair: Cristian Kirisits

Image registration, image matching and dose accumulation are important topics for brachytherapy. The matching of target volumes between different image modalities and images taken at different time points is challenging. Also the dose accumulation between fractionated brachytherapy treatments and combination with external beam has been topic of many analysis and recommendations. However, there are several misunderstandings when transferring models created for external beam to brachytherapy applications. This workpackage analysis the existing methods, the evidence from scientific and technical literature and would like to draw conclusions including expert opinions.

WP21 Calibration in high-energy photon brachytherapy

The WP21 group aim is to present guidance for brachytherapy (BT) high energy (HE) source calibrations, including practical aspects and issues not specifically accounted for in the former current and well-accepted societal recommendations. This European guideline report has impact to all European sites offering HDR/PDR BT to ensure a high quality in HE source calibration. This presented recommendations report complements for HE the recently published ACROP BRAPHYQS WP18 report dedicated to low energy (seeds) (Radiother Oncol 2019). With both reports, the medical physicist has available a set of clear societal recommendations to consistently address the aspects of BT source calibration.

In particular, the rationale and charges of WP21 is to guide users of HE HDR-PDR BT sources (Ir-192 and Co-60) on:

  • Calibration of HE sources and the instruments and to keep these efficiently operative (including an updated list of available calibration laboratories in Europe). Comparison of users RAKR measurements with manufacturer’s calibration, and required procedures when potential discrepancies exceed an action limit.
  • In addition, WP-21 evidenced that there is an ambiguous responsibility definition of source leakage verification, being also the aim of this report to help with this issue.

These recommendations will reflect the guidance to the ESTRO BT users and describe the procedures in a clinic or hospital to ensure the correct calibration of HE HDR (and PDR) sources.

WP21 Members:

Jose Perez-Calatayud (Spain), chair

Facundo Ballester (Spain), expert consultant

Dimos Baltas  (Germany), expert

Åsa Carlsson Tedgren (Sweden), expert

Larry DeWerd (USA), expert

Papagiannis Panagiotis (Greece), expert

Mark Rivard (USA), expert

Javier Vijande (Spain), expert

Frank-André Siebert (Germany), BRAPHYQS chair

WP22 Ru-106 eye plaque therapy

A new BRAPHYQS project on eye plaque treatments for uveal melanoma using Ru-106 plaques (WP22) was launched in 2020. Currently, the WP22 group is preparing a survey to map and analyze clinical practice, with particular emphasis on dose planning, prescription and source calibration.

In 2019 the TG-221 “AAPM recommendations on medical physics practices for ocular plaque brachytherapy: Report of task group 221” was published. This report mainly covers ocular brachytherapy using Iodine and Palladium seeds, but information on Ru-106 practice is limited. Therefore, we are also exploring the possibility of creating guiding documentation for clinical use of Ru-106 plaques, after finishing the survey.

This is a joint project together with the GEC-ESTRO head-and-neck working group (Chair: Luca Tagliaferri). In addition, some additional experts were invited to join. This working package is also supported by the industry, in particular by Eckert & Ziegler BEBIG.  Eckert & Ziegler BEBIG representatives are invited to join the working meetings.

WP22 Members:

Frank-André Siebert (Germany), BRAPHYQS chair

Åsa Carlsson Tedgren (Sweden), BRAPHYQS secretary

Marisol De Brabandere (Belgium), BRAPHYQS member

Luca Tagliaferri (Italy), Head & Neck and Skin WG chair

Lotte S. Fog (Australia), invited expert

Andrea Slocker (Spain), invited expert

Elisa Placidi (Italy), invited expert

Michael Andrássy (Germany) BRAPHYQS member, Eckert & Ziegler BEBIG representative

Carmen Schulz (Germany), Invited Eckert & Ziegler BEBIG representative