AccuBoost – non invasive, real-time, image guided breast boosting

October 20 2010  |  News Article 

A new treatment option for the boost dose as part of the Whole Breast Irradiation treatment after lumpectomy 

AccuBoost is a new system designed to allow non-invasive image-guided breast brachytherapy, or NIIGB. The new system includes a specifically adapted mammography station, a CR reader, a series of tungsten applicators and tools for applicator selection and positioning. The radiation source is the HDR microSelectron afterloader from Nucletron. This new system was designed specifically to address the practical and clinical issues in delivering the all-important boost dose, after whole breast irradiation as part of the care of women undergoing Breast Conserving Therapy (BCT) for early stage breast cancer.  The AccuBoost design gives the radiation oncologist the needed confidence that “you see what you treat and you treat what you see”.



Experience in a variety of clinical settings in the United States shows that AccuBoost can be easily implemented. In addition to providing a potential replacement for Linac-based electron boost therapy, radiotherapy departments have the opportunity to optimize department resource efficiency by making greater use of their HDR afterloader and at the same time free up Linac time. In the United States AccuBoost has been successfully used since 2007 in more than 35 oncology centers. AccuBoost is currently being introduced to Europe, and has been installed in the first centers in Italy and Spain. 

Clinical Experience with AccuBoost
Results of assessment of the ability of AccuBoost to target the boost volume and spare exposure to healthy tissues and organs were recently reported in a publication in the International Journal of Radiation Oncology Biology and Physics, or The Red Journal. 1  Researchers from Tufts University School of Medicine used a sophisticated method to model and review compared dose parameters of AccuBoost with conventional electron boost. The Tufts group also compared dose parameters of AccuBoost with 3D CRT, in terms of partial breast irradiation treatment.

A key finding of the study, performed in 8 patients who had undergone lumpectomy for early stage breast cancer, was that the amount of breast tissue targeted to receive the boost dose, the so called planning target volume or PTV, was significantly lower with AccuBoost than with conventional electron boost. However, key dosing benchmarks were maintained – in other words, the reduction in PTV and sparing of healthy tissue was not at the cost of delivering the necessary dose of radiation to the target. At the same time, the dose delivered to the skin was significantly lower with AccuBoost than with electron boost.  Dose to the chest with AccuBoost was one seventh of the dose with electron boosting – dose to the heart was one eleventh with AccuBoost of the dose with electrons. 

“Tumor bed boost is a critical component of successful breast conserving irradiation, but typical boost techniques have barely evolved in the past 10-20 years.”2 states Shirin Sioshansi, MD and lead author of the article. “When you combine the paucity of advancements in this area with the papers assessing that CT based targeting may not be as good as we think, NIIGBB becomes of keen interest. We must rethink the entire process of breast tumor bed dose so that it is delivered with the highest possible degree of accuracy and efficacy. The localization accuracy and immobilization of the breast allows for minimal margin expansion of the target volume,” according to Dr Shioshansi.

The first results from the US ‘AccuBoost Patient registry’ will be presented at the 33rd Annual San Antonio Breast Cancer Symposium, December 2010. 3

The registry has accumulated data from 9 US institutions that have shared their experience in treating their patientsThe primary purpose of the registry is to assess the feasibility, implementation and early observations of patients treated with AccuBoost. The major finding in the registry are the favorable cosmesis outcomes recorded in patients receiving AccuBoost.

About Brachytherapy
Brachytherapy is a high-precision radiation therapy, in which the radiation source used to kill cancer cells and shrink tumors is placed in or close to the tumor itself. Brachytherapy offers a precise, highly effective and well tolerated treatment option tailored to the needs of individual patients. The precision brachytherapy approach allows a physician to concentrate a high dose of radiation in a small area, minimizing damage to nearby, healthy body tissue and organs, over a shorter treatment period. Find more about brachytherapy on http://www.aboutbrachytherapy.com/.


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1 Sioshansi S et al. Int J Radiation Oncology Biol. Phys. 2010 (E Pub ahead of press)
2 Medical Physics Web. http://www.medicalphysicsweb.org/. Accessed October 26, 2010
3 S. Hamid1,2, D. E. Wazer1,2, et al, abstract accepted for presentation at the 33rd Annual San Antonio Breast Cancer Symposium, December 2010.