Hi everyone! A lot of you have been submitting YouTube comments and a lot of
you guys have questions on prostate cancer that you would like us to ask Dr. Scholz
and today we're going to answer those questions.
What's the status and reliability of liquid biopsy?
In liquid biopsy people, I think, sort of initially jumped to the thought, "Oh,
I don't have to have a needle biopsy if my PSA is high, and liquid biopsy isn't talking
about that. What they're talking about is in men with very advanced prostate cancer more and more
research is showing that if you biopsy a metastatic lesion like on a bone or in the liver
and analyze the genetics, it may guide you to a specific therapy that will be effective. And doing
biopsies of the liver or the bone is uncomfortable and difficult a little risky,
and so a liquid biopsy—something where you just do a blood test—is obviously very attractive.
And these types of blood tests do exist and are available one's called Guardant360
and other ones called FoundationOne and they appear to be about as accurate as
sticking needles into metastatic lesions. While a liquid biopsy is something that we use routinely
in our practice, it's for men that have very advanced treatment-resistant cancers
and we're trying to figure out if there's some available type of treatment that would help them.
Do you think in the future that the liquid biopsies will eliminate the,
you know, the actual bone biopsies and everything?
Well, I think they already have, yeah. There are doctors that are still doing the bone
biopsies and the liver biopsies but they are, you know, very cumbersome and uncomfortable and so
we don't really do any more bone or liver biopsies we only do liquid biopsies.
Our next question is Dr. Scholz, can you
please comment on post-radiation recurrence treatment options?
Well, that's a huge field and the book I wrote we call it Indigo. PSA relapse prostate cancer
presents in so many different forms it's very important to look at PSA doubling time
to see how serious it is; some men have very slow progressing cancers, others rapid,
and then of course the big breakthrough as we already mentioned is the advanced scanning
now that we have like Axumin and PSMA PET to find where the cancer is coming from and possibly treat
it or even cure it. So, I'd say that those are the two important take-home messages for PSA relapse,
but it's a vast field. I mean, you could write a whole book on PSA relapse prostate cancer
and the and the different ways to treat it and who should have treatment who shouldn't
have treatment, but the good news is with prostate cancer many men get a second chance,
sometimes even a third chance to cure the cancer even if it comes back and that's very unusual in
the in the cancer world. Most other cancers, if they come back, the situation's pretty
hopeless but with prostate cancer there's still hope that you might even be able to cure it.
So, I know you said it was a huge field but what if
the cancer relapse is exclusive to the prostate?
Yeah and that used to be a common problem with older types of radiation and it used to make
the surgeons tear their hair out because it's difficult to do an operation in a previously
radiated prostate, but now say we have one of these fancy PSMA PET scans and it shows there's
nothing outside, that it just came back inside the prostate, there's so many options. I mean, the
salvage cryotherapy, laser treatments, high-intensity focused ultrasound, other forms
of salvage radiation—salvage seed implants—can be readministered in men that have had previous
radiation. We don't see that problem as frequently now because modern radiation is so much more
thorough than what was available 15, 20 years ago, but if it does happen, there's lots of good
options now that people will have an excellent chance for cure with a second line therapy.
I'm glad you mentioned that because I think a lot of people don't think you can re-radiate
and so they automatically think if they failed radiation they have to go straight to surgery
and we see this myth come time and time again so...
It used to be true 15 years ago that was the only option, but
technology marches on and we have a lot of different options these days.
How are the toxicity levels if you're going to re-radiate? I know it obviously
would vary depending on the type of radiation, but I would imagine that
you've already had a certain set of side effects from the first radiation treatment;
would the second radiation treatment be more, you know?
Well, it depends a lot on the skill of the doctor. This is not the kind of thing you'd
have done by the corner radiation therapist; you want to go down to an academic center that has a
track record doing this, but my experience when, you know, seasoned experts are doing this type of
thing is that the toxicity is—really—it's not a major issue at all. These patients do quite well.
So our next question is quite interesting;
why do you not address the possibility of physical castration instead of all these
chemical treatments especially for a man in his mid-70s? The cost alone would kill him.
Well, most people have insurance if we're talking about the United States. The cost is almost never
an issue, but another consideration is that in this modern era many men are not getting lifelong
hormone treatment. Castration is a terrible word but whether they remove the testicles with a
surgical operation or you give men an injection that causes the testicles to stop functioning,
the therapeutic effect is equivalent, but the shots are reversible whereas the
men that have surgery, it's irreversible, and there are plenty of studies now showing that even
men that have incurable prostate cancer can safely take holidays—it's called intermittent therapy—and
allow their testosterone to come back and their quality of life to improve,
and it can be done in someone that's had surgical castration, you would actually have to give them
testosterone which a lot of people—not myself—but others are nervous about doing that. So, we we
don't order surgical castration in our patients, but perhaps in a poor country where the cost of
injectable therapy is high, that could be a consideration in people that have
advanced irreversible hormone-sensitive metastatic cancer. That is a potential
place where surgery could be used I suppose, though we don't use it here in the United States.
So our next question is, "Dr. Scholz, can you please explain
how and why some men are not suitable candidates for seed implants?
and how often..." Well, there are a couple questions here so let's start with that.
Well, men that have very very large prostates it's more difficult to do seed implants. If
there is just a section of the gland that has cancer one could do a focal seed implant.
The irritation of the urinary passage going through the prostate by radiation
becomes a bigger problem as the prostate gets larger and the dose of radiation gets larger.
So, men that have a lot of pre-existing urine urinary issues may not be good candidates for
seed implants either. And then, other than that, it would just be, I suppose,
people that aren't candidates for local therapy. If cancer's already spread somewhere, you know,
treating the prostate may no longer be appropriate although there's even debates about that,
but it's primarily either excess urinary problems or perhaps a a very very large prostate would be
potential counter-indications to doing a seed implant.
For people who have large prostates,
is there things that they can do to get it down so that they would be candidates?
Yes, it depends on how large it is but prostates can can be reduced in size with
hormone treatments, the prostate gland will get smaller, and that
may also, you know, may be possible to treat men that have these increased urinary symptoms
as well with various pharmaceutical agents and then they could become eligible for seed
implants. So it's not common for people to be ineligible for seed implants, but there
are certain situations where maybe another treatment would be better.
The same person asked, "How and why does calcification occur in the prostate?"
Well, calcification is a process that occurs over time in areas of scarring.
You can see calcification in the blood vessels which we call hardening of the arteries which
is an inflammation of the arterial wall and then after the inflammation settles
down it creates scar tissue and then the body deposits calcium in those areas of scarring,
and same thing happens in the prostate low-grade inflammation is extremely common in the prostate
and so you get areas of inflammation, then scarring, and then calcification.
It's it's a benign issue for the most part and it's extremely common when we do
high-resolution ultrasounds on men over age 50, more than half the men have significant
amounts of calcium in their prostate and it's part of the aging process.
Is it possible for a man to have seed implants where there is calcification?
Certainly, yeah. The calcium itself is a benign phenomena that doesn't preclude treatment.
Seed implants can easily be done. I think high-intensity focus ultrasound can be a
problem if there are large amounts of calcium but it's not a contraindication for seed implants.
Ine of the questions I've seen a couple times is people asking how much water they
should drink or their doctors telling them to drink water before the radiation treatment,
so I don't really think it's about the amount. Why do they have men drink water before radiation?
Well, as most people are aware, that the urinary bladder is very close to the prostate
and the prostate isn't like stuck to a bone or anything like that it can move around,
and the radiation doctors want to have the prostate in the same exact location every
time you go in for your radiation treatment; they want you to have the same amount of
bladder expansion or amount of urine in your bladder when you go in for the treatment. So they
want to develop consistency so they get greater accuracy with their radiation.
Thank you so much for watching. If you would like Dr. Scholz and I to cover one of your questions,
you can go ahead and leave them in the comments section of this YouTube
video or on our other videos and we can go ahead and pick them up from there. Also,
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