Video: HDR Brachytherapy Side Effects vs. Other Treatments | Ask a Prostate Expert, Dr. Jeffrey Demanes

Ask a Prostate Expert | Transcription

Alex: One of the things that I really want to talk about is the side effects because I think that a lot of times—I don't think the fact that surgery side effects and IMRT and everything, if patients know that there have been studies talking about these toxicity levels and brachy just comes out far and beyond, so can you speak to that? 

Dr. Demanes: Well, every treatment has its side effects and brachytherapy is no exception. The goal is to minimize the side effects while at the same time getting the maximum tumor control rates. When you use brachytherapy in prostate cancer, you can give a significantly higher dose than you can with other forms of radiation—external beam. Therefore, you tend to get higher tumor control rates. At the same time, you want to avoid treating the surrounding tissues: the rectum, which is sitting right behind the prostate, or the bladder, which is sitting right on top, or even the urethra, which runs right through the prostate. With the brachytherapy, if properly administered, the distribution that we get from HDR, for example, we know what the dose is to the bladder, the rectum, the urethra, and to the tumor before we push the button. Whereas with seed implants, the problem is you put the seeds in and then you do the calculations afterward based on where the seeds ended up, so you lose a little bit of control, and I'll reiterate that a good seed implant, for the right patient, you can't get a better therapy, but that the HDR is not only more reliable—that is, more patients will get a good seed implant—but you can also treat larger areas because the scaffolding allows you a broader range of treatment. 

The side effects that you get when you control the dose to the bladder and the rectum such as we do with HDR, for the rectal complications they're not zero, but they're pretty close to zero. Less than 1% of patients will get any significant rectal complications compared to the best radiation with external beam is 5 and more like 10%, and in the old days it used to be significantly higher, but we've made considerable advances with IMRT and SBRT so that the numbers are lower, but still, compared to external beam, properly administered brachytherapy is going to have the fewest rectal complications. That's a major advantage right there, even if the control rates are the same and I don't think they are. 

Compared to surgery, surgery you take an organ from between the container (the bladder) and the stopper or the sphincter that's just beyond the prostate, you remove that organ, and put the piping back together, and unfortunately, even in the best hands there's a certain leakage rate and the patients who have incontinence or leakage, that's a major quality of life deterrent. You can imagine going out and trying to play tennis and you're leaking and you have to wear pads and so on and so forth. Now, I don't mean to emphasize that all patients with surgery get leaking, but certainly more patients with surgery get leaking than patients who have radiation therapy in any form. So brachytherapy has the advantage of getting high control rates, avoiding the rectal complication rates, keeping the urinary complication rates at a relatively low level and avoiding incontinence. 

And I think the last thing that should be mentioned is sexual function preservations with brachytherapy. There are no perfectly designed studies where there's a perfect comparison between different modalities, but 5-year rates of 80% sexual preservation rates which we get with high dose-rate brachytherapy are among the best reported in the literature, and they certainly compare favorably if you have full out surgery and have to take both nerves, then you get no sexual function. In the optimal hands where you preserve both nerves, sexual function can preserve in about 80% of the patients and with external beam, probably a similar number. 

Alex: So, if you would like more information about anything we talked about, you can go ahead and contact our Helpline team and they will be available to talk to you. The number is at our website, PCRI.ORG, and you can look up other information on prostate cancer treatments. And if you like this video, go ahead and give us a thumbs up. The reason those thumbs-up matter is because that lets Google know that this video is helpful to you and it can help other patients and we get on a suggested videos list. Subscribe to our Youtube channel if you would like more information in general about prostate cancer. We cover every topic we could possibly think of and we hope you have a great week.