A radiation oncology company, Accuray has declared the publication of a study that supports the effectiveness of non-invasive delivery of high dose rate (HDR) brachytherapy dosing to prostate cancer patients. The University of California—San Francisco (UCSF) study appeared in the January 2012 issue of the International Journal of Radiation Oncology - Biology – Physics.
To support this concept, patients with prostate cancer were treated with stereotactic body radiotherapy (SBRT) by utilizing Accuray's CyberKnife Robotic Radiosurgery System in a way that imitates HDR brachytherapy dosing in the prostate gland.
The study used a radiation dose scheme, which was similar to that of a standard invasive HDR brachytherapy to supply high doses of radiation to areas where the prostate gland had a higher rate of prostate cancer cells. This technique was different from the usual method of delivering a single dose of radiation. Patients who had organ confined prostate cancer were made to undergo four treatment sessions. Ideally, HDR brachytherapy is effective in treating prostate cancer. However, in this technique, invasive catheters are inserted into the prostate which makes it difficult for patients and also presents a daunting task to the doctors. The CyberKnife System can rapidly and easily imitate this treatment in a noninvasive way as it can produce and paint complex doses in the prostate gland.
A study was conducted on 38 patients, who were in their mid-fifties to early eighties, with a follow-up of one year. Among the 38 patients, 20 were treated with CyberKnife SBRT monotherapy, while the remaining ones were treated with CyberKnife SBRT boost after external beam radiotherapy (EBRT). The study indicated that CyberKnife SBRT was tolerated well, reported no progression and had 100% survival rate.
Siavash Jabbari, M.D., a radiation oncologist at Advocate Lutheran General Hospital and lead author of the UCSF study, stated that the CyberKnife System allows them to mimic HDR brachytherapy dosimetry and these outcomes indicate that exceptional clinical results can be achieved without the disadvantages of HDR brachytherapy.