What types of brachytherapy can be used for treatment of this cancer type?

Brachytherapy is a type of radiation therapy to treat breast cancer. After surgery, brachytherapy is commonly used to kill any remaining cancer cells.1

High Dose Rate (HDR) brachytherapy can be given after the whole breast has been treated using external beam radiotherapy, known as whole breast irradiation (WBI). In this instance, brachytherapy provides a ‘boost’ of radiation just to the area where the tumor was.2

Alternatively, HDR brachytherapy can be used as the sole method of radiotherapy after surgery, known as accelerated partial breast irradiation (APBI). This provides targeted radiation to just the area around where the tumor was and can be completed much more quickly than WBI.2

Depending on the doctor preference, brachytherapy can be performed with balloon, hybrid device (SAVI) or using multicatheter interstitial technique.1 The most used APBI brachytherapy technique in clinical practice is multicatheter interstitial brachytherapy.

Modern brachytherapy uses Computed Tomography (CT) images to control the position of the tumor and the radioactive source. This type of brachytherapy is called Image-guided or 3D brachytherapy.

How brachytherapy for this cancer type is performed.

How effective is brachytherapy?

The European multicenter randomised trial compared treatment outcome of patients with early breast cancer treated with WBI and APBI. It showed similar results for both treatments after 5 years. Since with APBI only a small part of the breast is irradiated, APBI has advantages over WBI: less radiation dose to the heart (less risk of ischemic disease) and less radiation dose to the lungs (less risk for secondary lung cancer).3

Picture 1. Overall survival in patients with early breast cancer treated with WBI and APBI3

Another paper analyzed side-effects and cosmetic results in women who participated in the above mentioned European multicenter trial.

After five years, women treated with APBI had significantly less serious skin side effects (like hyperpigmentation, telangiectasia, fibrosis, necrosis) compared to WBI.

This clinical data supports the use of APBI with multicatheter interstitial brachytherapy as an alternative to whole breast irradiation.

Picture 2. Cumulative incidence of serious skin side effects in patients with early breast cancer treated with WBI and APBI4

References

  1. Skowronek J et al. Journal of Contemporary Brachytherapy 2012; 4(3):152-64. Available at: https://www.termedia.pl/Review-article-Brachytherapy-in-accelerated-partial-breast-irradiation-APBI-review-of-treatment-methods,54,19362,0,1.html Accessed June 2021
  2. Strnad V et al. Radiotherapy and Oncology 2018; 128(3);411-420. Available at: https://www.thegreenjournal.com/article/S0167-8140(18)30197-X/fulltext Accessed June 2021
  3. Strnad V et al. Lancet 2016 Jan; 387: 229-38. Available at: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)00471-7/fulltext Accessed June 2021
  4. Polgar C et al. Lancet 2017; 18(2);259-268. Available at: https://www.thelancet.com/journals/lanonc/article/PIIS1470-2045(17)30011-6/fulltext Accessed June 2021