Hi, I’m Dr. Scholz. Let’s talk about prostate cancer.
So in this video, we are going to cover an important treatment for intermediate risk
or Teal prostate cancer called High Dose Rate Temporary Seeds or “HDR.” Seed implantation
comes in two forms. You can look at our video on permanent seeds, which is the most popular
type of seed implant. In this particular type of seed implant, the seeds are put in, in
the hospital and then removed before you go home. Thus, the designation of temporary seeds.
Whenever you’re thinking about treatment with seed implants, whether it be permanent
or temporary, you need to seek out the best practitioner. These are skilled procedures
just like a good operation, a good surgeon is needed—for seed implants, you need an
experienced and well-trained seed implanter.
I’m often asked should someone do temporary seeds or permanent seeds. All things being
equal, the skill level of that doctor is more important than whether you do permanent or
temporary seeds. Permanent seeds are more convenient and therefore tend to be more popular.
That doesn’t mean that they work better or worse. When considering doing a seed implant,
the question always comes up as to whether or not you should add external beam radiation,
so called IMRT or intensity modulated radiation. Typically, if you’ve looked at the PCRI
staging program, men who are getting staged as Basic-Teal can have a seed implant without
any external beam radiation. Men who are in the category of High-Teal should consider
a seed implant in combination with external beam radiation. This is true with permanent
seeds or temporary seeds.
So we’ve talked about temporary seeds; what actually are temporary seeds? Temporary seeds
use catheters, and I’m not talking about urinary catheters; I’m talking about little
hollow tubes that are placed while the patient is in the hospital through the skin of the
perineum (this is the skin between the scrotum and the anus) and left in place for at least
six hours and sometimes as long as twenty-four hours. While the patient is in the hospital
a very high intensity iridium seed will be placed at the end of the catheter and then
slowly pulled back in the area where the prostate is to administer the radiation. Two or three
such cycles may done during the hospitalization—perhaps every six to eight hours. That’s the essence
of temporary seeds.
The issue with temporary seeds therefore is that you have to be in the hospital and these
catheters remain in place throughout the hospitalization so that means the patient has to be semi-immobilized.
No one wants the catheter to shift around and create inaccuracies of treatment. So a
temporary seed implant is a more complex and involved procedure than a permanent seed implant,
and when you compare these two options that could be considered a disadvantage for temporary
seeds compared to permanent seeds. So what is the advantage of doing a temporary seed
procedure if a permanent seed procedure can be done more conveniently? Probably the one
advantage is that because of the very fast delivery of radiation there’s some suggestion,
not proof, but some suggestion that the anticancer efficacy may be enhanced to some degree. Another
advantage is that because catheters can be placed around the prostate—whereas permanent
seeds can only be placed within the prostate—the doctor doing a temporary seed implant can
steer the radiation out around the gland more easily. This becomes a real issue if, for
example, you want to treat the seminal vesicles—the little rabbit ears at the top of the prostate.
It’s much easier to do that with a temporary seed implant than with a permanent seed implant.
Briefly, let’s talk about side-effects. Side-effects of a temporary seed implant are
very similar to that of a permanent seed implant. There is a risk of erectile dysfunction. There
is a risk of inflammation of the urinary passage through the prostate called the urethra. Inflammation
is called urethritis. Short-term urethritis occurs with seed implants and may last from
anywhere from three and eight weeks. The problem is that a small percentage can have long-term
urethritis which translates into more frequent urination during the day, getting up at night,
discomfort with urination. There are treatments for this, and if the treatments were perfect
we wouldn’t be discussing it, so some people are left with ongoing symptoms. In a skillfully
performed seed implant, you’re looking at a risk of maybe 5-15% of such problems like
long-term urethritis. A very small percentage of people that have urethritis can develop
scarring or stricture, this means that the passageway of urine—of the urethra—is
obstructed, and if that occurs (this can also occur with surgery, permanent seed implants,
and perhaps less frequently with external beam radiation) the area needs to be stretched
out, and in some cases scar tissue doesn’t stretch very well and very rarely it can translate
into incontinence. This complication may occur anywhere from 1-3% of the time in men that
have this type of treatment.
One issue that comes up is monitoring for a cancer relapse after treatment. When men
have surgery, the prostate is removed completely and the PSA should be zero. If there is any
detectable PSA that’s a very strong sign the cancer is back. After radiation, be it
a seed implant or external beam, the prostate is still in place and will produce some PSA.
There’s no absolute threshold of what’s normal and abnormal, but typically a cutoff
of a PSA of around 1 can be considered a level for concern if the PSA goes above 1. Another
phenomenon is the temporary rise of PSA above 1, perhaps even higher than that, due to delayed
inflammation in the prostate called the “PSA bump.” This occurs after high dose rate
seeds in as many as 25 or 30% of men. It can occur up to three years after the seed implant
is performed creating all kinds of confusion and difficulty in certain cases. When that
happens people need to be simply watched closely and try and observe for an erratic pattern
of PSA jumping around which is more consistent with inflammation versus a steady incremental
unremitting rise of PSA which is more consistent with a cancer relapse.
So in conclusion, seed implants, in my opinion, should be at the top of the list as a consideration
for treatment for therapy for men with Teal. The cure rates are better than the other options
and the side-effects are certainly no worse and of course, compared to surgery they’re
much less. When trying to make a distinction between doing a high dose rate seed implant
versus permanent seeds, both of which are good options, I would go with the more experienced
practitioner. The inconvenience of going in the hospital for one night or maybe two nights
is small compared to the problems that can happen when a seed implant is done unskillfully.
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