HDR Prostate Brachytherapy: Exciting Advancements through Clinical Trials
September 27, 2012
In my last post, I referred to two clinical trials involving High Dose Rate prostate brachytherapy that have been made possible through donor support. This week, I'd like to share with you the importance of the first of these trials.
Patients often find it hard to relate to clinical studies and the chance for success can be very slim. The reason that people often do participate is because of a desire to help others and add to a knowledge base that will help future patients with their condition. As a researcher, I am extremely grateful for this altruism. Every step, no matter how small it seems, is a step forward.
The first HDR prostate brachytherapy trial has had a direct benefit for men with prostate cancer considering curative radiotherapy. HDR prostate brachytherapy has proven to be highly effective with excellent long term results, but until recently it required a full-day procedure. It was time consuming for the radiation oncologist and long and uncomfortable for the patient. The complex planning for the HDR radiation treatment began with CT images that showed where the organs would be contoured and the needles inserted. The tiny HDR radiation source could then be programmed to travel through the needles, pausing for the right amount of time in each spot to deliver the correct dose. The average length of time between needle insertion under anesthesia and final treatment delivery was about six hours – a very long time to remain absolutely still.
Recently, advances in imaging and programming have allowed the entire procedure to be completed using only ultrasound guidance, without transferring the patient multiple times for CT scanning and treatment delivery. This means the whole treatment can be delivered in the operating room with the patient asleep. It generally takes about two hours from the time the patient is put under anesthesia until the treatment is delivered.
The purpose of our first clinical trial was to ensure that ultrasound guidance was as accurate as CT guidance. Twenty-five patients participated in the study and we found that a) ultrasound-based planning can safely replace the old CT-based planning, b) the needles can be just as accurately seen and identified, and c) the whole treatment process can be completed without any discomfort to the patient. Thanks to these findings, all patients undergoing HDR prostate brachytherapy treatment in B.C. will now have the ultrasound-based procedure, comfortably asleep from start to finish. Next week I'll describe the second HDR study which is ongoing.