Breast brachytherapy

Patient Specific Breast Brachytherapy Templates for Immobilization and Guidance

Breast cancer treatment currently consists of surgical tumor removal followed by radiation therapy. The standard of irradiating the whole breast during therapy, however, requires 5-7 weeks. This causes many candidate patients to rely on other quicker methods of treatment instead, such as radical breast removal surgery.

Currently, there are two main types of breast radiation treatments - external beam radiotherapy (EBRT) and brachytherapy. EBRT delivers radiation externally making it dangerous to both the skin and vital organs situated near the chest wall, but is the current standard of treatment for breast conservation (Wong, 2005). In breast cancer, an external beam delivers a dose of radiation to the whole breast and is performed for a period of 5 to 7 weeks (Buchholz, 2009). The treatment produces high local control rates of > 90 % and provides strong cosmetic results (Kelley, 2007). Brachytherapy, on the other hand, is an internal procedure which reduces damage to the skin and allows for the localization of the radiation dose around the tumor as opposed to the whole breast, therefore optimizing for minimal radiation to vital organs (Kelley, 2007). Radioactive sources or seeds are either implanted or come into contact with the tissue at risk. These seeds emit radiation outward, localizing the radiation to specific areas. Brachytherapy also has the advantage of reducing patient hospital time as the treatment can be completed over the course of a week rather than over several weeks.

Brachytherapy, a radiation therapy which requires only one week, has the potential to become the standard treatment post-operatively. Brachytherapy treatment relies heavily on accurate catheter insertion and dose coverage; thus, immobilization and guidance are key factors in strong brachytherapy treatments.

The purpose of this work is to contribute to the breast brachytherapy protocol but reducing one patient visit and improving the comfort of the patients during a procedure through the use of a patient specific template with pre-planned catheter insertion site. A plethora of immobilization devices exist for external beam treatment, but the standard of care for brachytherapy consists of the Kuske applicator in conjunction with some imaging modality. Guidance systems are improving, but the option for better stabilization in brachytherapy is still available. We would like to show that the use of patient specific templates in breast brachytherapy is a feasible alternative to current practice.