The Breast Cancer Working Group (BCWG) of GEC-ESTRO deals with clinical and technical issues of breast brachytherapy. In the last decade the BCWG work mainly focused on the indications, techniques and quality assurance of traditional breast brachytherapy used as a boost after external beam whole breast irradiation. A successful cornerstone of this era was the ”Consensus Meeting on Breast Cancer: To Boost or Not to Boost and How to Do It” directed by Drs. Hammer and Van Limbergen at the 2001 Annual GEC-ESTRO Meeting in Stresa, Italy.

During the last two decades, the new concept of accelerated partial breast irradiation (APBI) opened a new perspective for breast brachytherapy. Reexcision followed by reirradiation using interstitial breast implants has been also implemented as an alternative to mastectomy to treat ipsilateral breast local recurrence after previous breast-conserving therapy.

In the last decade, several groups have implemented multicatheter brachytherapy technique (instead of the traditionally used rigid needle technique) and 3-D CT image-based brachytherapy treatment planning for the management of breast cancer. These developments all together opened new horizon for clinical research in breast brachytherapy.

In the past few years motivated young colleagues have joined the experienced core of the BCWG. Recently the group has a couple of ongoing projects:

1. Multicentric Phase III APBI Trial

One of the most important projects of the BCWG was the development and conduction of the first European multicentric breast brachytherapy trial comparing the efficacy of multicatheter APBI to conventional whole breast irradiation. The study was supported by a grant from the German Cancer Aid. Between May 2004 and July 2009, 1233 patients have been randomized in 16 centers from 7 European countries For moe information, please click on the  APBI Trial website.

The first results of this landmark study hopefully will be available for the radiation oncology community in the next World Brachytherapy Meeting in 2012 in Barcelona.

2. Development of guidelines and recommendations for breast brachytherapy  

The group has started to develop guidelines for breast brachytherapy. The first guideline published very recently in Radiotherapy and Oncology gives recommendations on patient selection for APBI based on a systematic review.

A similar recommendation on boost brachytherapy (coordinated by Alfredo Polo) is under construction.  

Development of technical recommendations on target volume definition for breast brachytherapy is the next important project of the group. Actually two subgroups are working on this project: recommendations on PTV definition after “closed cavity surgery” is elaborated by the leadership of Vratislav Strnad (who is also serving the BCWG as secretary); while the subgroup working on recommendations after ”open cavity surgery” is coordinated by Csaba Polgár and Tibor Major.

3. Multicentric Phase III Breast Brachytherapy Boost Trial

Future plans include the development of a new clinical trial protocol comparing the efficacy, cosmetic results and side-effects of multicatheter brachytherapy boost to 3-D conformal external beam boost. This multicentric Phase III clinical trial would need the participation of at least 3000 patients. We hope that some industrial support will be available for the organization of this important clinical trial.  

Breast brachytherapy has clearly developed considerably in the last two decades. Based on the obvious dosimetric advantages of interstitial breast implants (over external beam techniques) supported by the encouraging results of modern boost series utilizing stepping-source afterloading technology, multicatheter HDR/PDR brachytherapy remains a standard treatment option for boosting the tumour bed after breast-conserving surgery and whole breast irradiation.

Reexcision followed by reirradiation using interstitial breast implants has been also implemented as an alternative to mastectomy for the management of ipsilateral breast local recurrence after previous breast-conserving therapy. Promising single-institution experiences warrant further prospective studies to explore the possible advantages of salvage breast brachytherapy.

APBI is an attractive treatment approach with considerable advantages over conventional whole breast irradiation opening new prospects for breast brachytherapy. Contemporary APBI trials using interstitial or intracavitary brachytherapy using strict patient selection criteria, and systematic QA procedures resulted in an annual local recurrence rate <1%.

Development of new standards for 3-D CT image-based brachytherapy treatment planning together with the implementation of inverse dose planning will further improve the conformity of dose distribution delivered by multi-catheter implants maximizing the ballistic advantage of breast brachytherapy.

However there are still many areas of uncertainty requiring further investigation.

The BCWG meets twice a year to discuss progress on current and proposals for future projects. We would welcome new active members for a joint adventure for the future of breast brachytherapy!  

Contacts: Jean-Michel Hannoun-Levi, Chairman, Breast Cancer Working Group of GEC-ESTRO or Charline Muco at ESTRO.

References:
Antonucci JV, Wallace M, Goldstein NS, et al: Differences in patterns of failure in patients treated with accelerated partial breast irradiation versus whole-breast irradiation: a matched-pair analysis with 10-year follow-up. Int J Radiat Oncol Biol Phys 2009;74:447-452

Johansson B, Karlsson L, Liljegren G, et al. Pulsed dose rate brachytherapy as the sole adjuvant radiotherapy after breast-conserving surgery of T1-T2 breast cancer: First long time results from a clinical study. Radiother Oncol 2009;90:30-35

Major T, Fröhlich G, Lövey K, et al: Dosimetric experience with accelerated partial breast irradiation using image-guided interstitial brachytherapy. Radiother Oncol 2009; 90:48-55

Ott OJ, Hildebrandt G, Pötter R, et al. Accelerated partial breast irradiation with multi-catheter brachytherapy: Local control, side effects and cosmetic outcome for 274 patients. Results of the German-Austrian multi-centre trial. Radiother Oncol 2007;82:281-286

Polgár C, Major T: Current status and perspective of brachytherapy for breast cancer. Int J Clin Oncol 2009; 14:7-24

Polgár C, Major T, Fodor J, et al: Accelerated partial breast irradiation using high-dose-rate interstitial brachytherapy: 12-year update of a prospective clinical study. Radiother Oncol 2010; 94:274-279

Polgár C, Van Limbergen E, Pötter R, Kovács G, Polo A, Lyczek J, Hildebrandt G, Niehoff P, Guinot JL, Guedea F, Johansson B, Ott OJ, Major T, Strnad V: Patient selection for accelerated partial breast irradiation (APBI) after breast-conserving surgery: Recommendations of the Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) Breast Cancer Working Group based on clinical evidence (2009) Radiother Oncol 2010; 94:264-273