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.
So, Dr. Scholz, we've categorized some of the questions that we've gotten on YouTube and today
we would like to cover a whole lot of them, but the first category we're going to be talking about
risk. So, I'm just going to go ahead and read our you know prostate cancer patient comments
verbatim and then you can go ahead and we can hear your answer. So, our first question is that
this person read an article on the internet back in 2008 and that it said that people who had hip
x-rays have a two to five times more likely chance of developing prostate cancer and he's concerned
because his father's been diagnosed with prostate cancer at 68 years old and he's now 36 and he had
a hip x-ray—a person who's 36—had a hip x-ray a couple months ago and they want to know because
they're having a lot of anxiety do they now have this increased risk of developing prostate cancer?
I don't think so. The family history, someone with prostate cancer who's you know whose dad is
now 68 is typical for people that get prostate cancer that don't have a family history. So,
the risk with any family history does probably double but the good news is that people who are
going to be diagnosed with prostate cancer in the next 5, 10, 15 years—you mentioned he's 35
years old—the good news is that the advancements in treatment and diagnosis are getting to be so
sophisticated and so effective that the risk of mortality is going to keep dropping and dropping
and the danger of nasty side effects is also going to be improving steadily.
So I would just advise this person to check their PSA every year starting at age 40 and and don't
worry about it—that modern medicine is going to catch up more quickly than any cancer will,
and I don't think the x-rays are going to translate into a higher risk.
Our next question is is there any evidence of a needle biopsy
leading to metastatic prostate cancer?
There is tiny evidence that prostate cancer can be left in the track of the needle where it goes
through the rectal wall into the prostate and contacts the cancer and then gets pulled back.
Those reports are exceedingly rare but there have been occasions that that's been documented.
The circulating tumor cell technology can show circulating tumor cells after a biopsy, so the
issue of course is that you can see circulating tumor cells in people that don't have a biopsy.
So we don't believe that the needle biopsies are enhancing the risk of metastasis beyond
the risk that people already have because they have prostate cancer
and the fact that about a million men are being biopsied every year and that the rates of
metastasis have been steady for so long suggests that the needle biopsy is not impacting that risk.
We're going to go into active surveillance now, so a couple questions on that. How many biopsies are
effective or needed during active surveillance, so what's the criteria of a biopsy being effective?
One question that comes up when you're doing random biopsies—I'm not a big fan of random
biopsies but they're still very popular—how many needle cores are necessary to do an adequate
random biopsy and with normal-sized prostates the number is probably around eight. Typically doctors
are doing around 12 and then in men that have really large prostates they need more than 12 to
cover the territory of a big prostate. So the the number of needle cores will go up or down based on
the size of the prostate and also based on the beliefs of the doctor who's doing the biopsy.
The other question would be how frequently should men on active surveillance get random biopsies and
I, again, I think that random biopsies were for an era when we didn't have multi-parametric MRIs but
there are many parts of the world where they don't use multi-parametric MRIs and even in
the united states they, unfortunately, they're still not doing MRIs instead of biopsies, but
for the places that are relying exclusively on biopsies to do active surveillance,
the general feeling is that a random biopsy should be repeated every two to three years assuming that
there are no new bumps felt on digital rectal, that the PSA is not misbehaving and that
the the periodicity of the biopsies should probably be about every two to three years.
So you kind of answered this already but the next question is really can an MRI
be sufficient so you don't have to have a biopsy whatsoever in active surveillance?
Well, the academic literature would contend that, no, that if you're going to do active surveillance
that you should do random biopsies; however, there are head-head studies comparing the accuracy of
random biopsies with MRIs—old-fashioned MRIs—showing that the old-fashioned MRIs
are more accurate than the biopsies are. There was recently an article in the New England Journal of
Medicine that very nicely outlined that if you have a good MRI and a targeted biopsy
that it will miss small higher-grade lesions about five percent of the time
and therefore some have advocated that people have both a targeted biopsy with an MRI plus a
random biopsy to be 100% sure. In my view the argument against that is that we already know
that we're over diagnosing prostate cancer and we don't want to even become more thorough at finding
little tiny cancers. I would suggest just rely on the MRI and then perhaps repeat the MRI annually,
assuming of course you have access to a quality MRI center. But that's an opinion,
the real standard that's being utilized throughout the urology world is to do random biopsies.
Our next question really comes into the tissue samples that they're getting from a biopsy
and it's in four plus three, so the question is can you discuss the importance of one tissue exam
being a four plus three versus, let's say, six or more being four plus threes.
So, tumor volume—how big the tumor is—is an important thing to know just as tumor grade—how
aggressive the tumor is—is an important thing to know and those are separate indicators—separate
metrics—that doctors use to estimate the chance for spread. Bigger tumors spread
more easily and higher-grade tumors spread more easily, so you can see that you could have a
small high-grade tumor, a large high-grade tumor, a small low-grade tumor, and a large low-grade
tumor, so four different categories. And the grade is more important than the size, so doctors are
always looking first at the Gleason score but then as a secondary issue they look at how big it is
and it may be just that if it's bigger there's a chance that there are other high-grade elements
that are being missed because remember the biopsy is only sampling a small section and so it may be
all about grade but just that bigger tumors have more hidden areas of higher-grade disease.
So, it's not all entirely clear, but when people are estimating the chance for spread which is
what drives whether people need treatment and how aggressive the treatment should be, they're
looking at both of those factors: the grade and then the size of the tumor which we're looking
at indirectly with a random biopsy because if you have six cores—unless you're putting all six cores
in the same place—that you have a larger tumor because it's spread out more throughout the gland.
So when you say small versus large, how do you as a medical oncologist measure that?
Well, if you're doing an MRI you could just look at the maximum diameter of the spot—the
lesion—that's being detected. So small lesions are probably five to ten millimeters; medium-sized
lesions are perhaps 10 to 20 millimeters; and you get above 20-25 millimeters you're looking
at something more than an inch across so you're getting into the large category,
and then, of course, when you get beyond that patients have cancer
that's literally growing outside the prostate or into the seminal vesicles.
So from a random needle biopsy they can't tell the size of the tumor?
Well, they put the needles in a grid pattern and so and
if it's properly done they'll label what part of the prostate each needle came from
and, then, so if you have a half a dozen cores spread out over the right side and all six cores
have cancer in them you can assume that the tumor extends from the top to the bottom of the gland.
Our next question is quite intriguing to me because it it's two different sides of the
coin here, so what if you have a Gleason score of nine but a PSA of 0.65? So you have a really high
Gleason score and then you have a really low PSA and I don't think that's a common thing, is it?
No, it's not. Having a very high gleason score is not common; having it paired with a very
low PSA is—it happens—it's not super common. Typically people like this are diagnosed because
someone could feel a bump on the digital rectal exam, so this is one of the arguments for why
when people get annual screening with PSA testing that the doctor should also do a finger exam. PSA
is going to pick up 95 percent of the prostate cancers but you can have low PSA producing cancers
that might be felt with a finger exam and I presume that's how this person was diagnosed. So,
low PSA producing cancers they have argued are somewhat more dangerous than ones that produce
normal amounts of PSA. That may simply be because there's a delay in diagnosis; PSA didn't go up so
no one did a digital rectal and then the disease turns out to be more advanced when it's detected,
or it may actually be a biologic variant that the types of cancers that don't make as much PSA are a
little bit more dangerous. Gleason 9 is already what we consider a high-risk, therefore it's
dangerous, but it's still curable, and the idea of having a very low PSA at the same time is—it's
well understood in prostate cancer circles. It is a minority situation, but it happens.
You as a medical oncologist being this prostate expert for 25 years,
I mean do you suggest that all men get digital rectal exams then including on
top of the PSA because I've had people ask me should I just get the PSA test then?
Well some people have argued that because men detest digital rectal
exams so much that they may be unwilling to show up for the PSA test that they can skip
the digital rectal exam and if men are bound and determined to avoid a digital rectal exam
i would certainly feel bad if they didn't get a PSA test if the digital rectal exam
scared them away and they didn't get a PSA test then that would be a big loss,
but for the men that are want to be thorough and careful and ensure that something isn't missed
they should have a digital rectal exam once a year as right along with the PSA.
So, our next question is how dangerous is Gleason 10?
It's more dangerous than other types of prostate cancer but that's not saying that much because a
lot of other types of prostate cancer are not dangerous at all. It's curable, Gleason 10 is
curable, and it depends on how high the PSA is, how large the tumor is, has it spread already.
If you look at localized Gleason 10 with a PSA less than 10 to start with and it's not a big
tumor that you can feel with your finger, cure rates are well over 50 percent with radiation
and hormone therapy. So it's still curable; it's controllable for many years in the men that aren't
cured, but that's not like an intermediate-risk where the cure rates are 95%. With the Gleason
10 and a low PSA that isn't too large, the cure rates may be in the 75 to 80% range.
Which is still rather high compared to a lot of cancers.
Absolutely.
Yeah, I think we get so many people that call us and they see Gleason 10 on the pathology report
and they—I mean obviously there's an immense amount of fear especially when we're talking
Gleason 6 to 10, and I think that talking about that cure rate is really important.
Yeah, there's already a lot of fear even in the men that have Gleason 6, and so
the idea that it's not only prostate cancer which
people are afraid of but it's a bad type of prostate cancer that incites even more fear.
It's certainly to be respected; it needs to be treated with expertise, but it's still curable.
Right, I think another point that I would like to talk about is the fact that when
you have Gleason 10, your treatment and going on treatment is a lot more rapid
than Gleason 6. Because prostate cancer is slow-growing naturally,
is Gleason 10 even slow-growing or do they need to deal with it right then and there?
It's slow-growing compared to pancreas cancer and lung cancer and brain cancer
but it's faster-growing than a Gleason 6 because those don't grow at all.
So, it depends on what you compare it with.
Right.
Thank you guys so much for commenting on our YouTube videos. We really
appreciate your questions and it's an honor to be able to answer them.
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