Finding Focal Therapy

Focal therapy treats only the section of the prostate gland that contains the cancer. These treatments appeal to men who want to preserve sexual and urinary function while trying for a cure. There are numerous types of focal therapies but they are all still in the research phase and much is still unknown about outcomes and risk of side effects.

This episode of PROSTATE PROS introduces listeners to focal treatment options and discusses benefits and drawbacks of these new, experimental therapies. Discover how to find experts and where to access the latest information on focal therapy.

Dr. Scholz:      [00:04] Welcome to PROSTATE PROS. I'm Dr. Mark Scholz and this is my cohost Liz Graves. 

Liz:      [00:09] Traditional treatments like surgery and radiation treat the entire prostate gland. This episode we're going to talk about focal therapy, which is a type of treatment that's directed at the section of the gland where the tumor is.  Focal therapy may appeal to men who want to reduce the risk of common treatment side effects. 

Dr. Scholz:      [00:32] Men are often surprised when they hear that standard treatment targets the whole gland.  Why would they do that?  When women have breast cancer treatment, they just take the cancer out.  They don't take the whole breast off anymore, at least not very often.  The answer is, of course, that until recently we didn't have accurate imaging that could delineate exactly where the cancer is located in the prostate.  Now that we have that ability to know where the cancer is, it's very logical to pursue treatments that are directed at the tumor instead of destroying the whole gland. 

Liz:      [01:10] So by not destroying the whole gland, you can preserve things like sexual function and urinary function. 

Dr. Scholz:     [01:17] Exactly.  With modern radiation treatment, thankfully, urinary function is generally not impaired.  But if you take your average 60, 65-year-old who has standard radiation, excellent work at a state of the art facility, there is up to a 50/50 chance that he's not going to be able to get erections unless he gives himself a shot in the penis or has a prosthetic device put in his penis afterwards, I mean total impotence that doesn't respond to Viagra or Cialis. 

Liz:      [01:50] So does focal therapy really help prevent these things from happening? 

Dr. Scholz:      [01:55] I don't think there's any doubt that when you just treat a section of the prostate, that the chances for maintaining sexual function are much better. Now we're going to go through and talk about some different approaches and some of the methods seem to have somewhat better or less likely problems with impotence, but there is always going to be a small risk, but the risk is much less. 

Liz:      [02:21] This sounds like a pretty appealing treatment choice.  Can we talk about who is eligible for focal therapies? 

Dr. Scholz:      [02:27] The spot of cancer needs to be visible on a scan.  Some men have very tiny areas or others may have two or three spots on perhaps on both sides of the gland. These sorts of things don't really lend themselves to the possibility of focal therapy, but a good number of men have a visible cancer that's been biopsy proven and there's really no evidence of anything on the other side of the prostate. 

Liz:      [02:54] What about the stage of men with prostate cancer?  Who's looking at this treatment? 

Dr. Scholz:      [03:00] That's a really good question because everyone's been so nervous about the deadliness of prostate cancer. Of course, over the last 10, 15 years, we've learned that it's nowhere near as deadly as we thought it was and so the thinking is changing.  I will tell you that since focal therapy, and we'll go into some of the details about the different types, is still an experimental area, the natural tendency is to only use it for people that have Intermediate-Risk, prostate cancer.  In other words, that have relatively small chance of cancer somewhere else in the body.  The reason that doctors lean towards Intermediate-Risk is to protect themselves, because High-Risk cancers are more likely to have spread.  If you give an experimental treatment and things don't turn out well in the long term, the doctors are concerned that they're going to be blamed for that bad outcome.  So focal therapy is feasible for both Intermediate and High-Risk, but more often than not as being used for Intermediate-Risk and not so much for High-Risk. 

Liz:      [04:02] Well what about Low-Risk prostate cancer? 

Dr. Scholz:      [04:05] So Low-Risk is where a lot of the focal studies have been done, which seems kind of ridiculous since we now know that Low-Risk prostate cancer can't and doesn't spread.  So the thinking unfortunately has evolved very slowly and yes, men with Low-Risk disease still get treatment.  So I suppose if someone with Low-Risk is bound and determined to have treatment and they have a visible spot, a focal treatment might be better.  Since we're not really worried about the cancer coming back because Low-Risk we consider to be harmless. 

Liz:      [04:40] I've read the prostate size also matters for focal therapy. Can you talk a little bit about that? 

Dr. Scholz:  [04:46] So in a couple of ways.  Maybe this is where we get into some of the many different types of focal therapies. The size of the prostate is relevant for one type of treatment, which is called HIFU, high-intensity focused ultrasound, because if the prostate gets too big, the HIFU beam can't reach toward the front of the gland.  So prostates over 40 CC start to present a problem. On the other hand, men with really big prostates may do better with some of the other focal therapies because you've got a bigger territory to work with. So for things like cryotherapy or laser, it might actually be better to have a bigger prostate.  If you think about it, if someone has a tiny prostate and wants to do focal therapy and you treat a certain section of that tiny prostate, maybe you're treating half the gland.  On the other hand, if someone has a gigantic prostate, if you’re treating that same size section, maybe it's only 10% of the gland, so you're less likely to cause harm in a big gland than you are in a small gland. 

Liz:      [05:51] Okay, so let's talk about the types of focal therapy you just mentioned: HIFU, cryo, and laser. 

Dr. Scholz:      [05:58] Let's get started with HIFU.  But before we talk about the types and there's seven or eight of these we're going to cover briefly, we really need to talk about the doctor doing the treatment. We're talking about trying to find William Tell, someone that hits the bullseye every time. I've had a lot of patients that have gone through focal therapy at reputable centers and then come to me, you know, a year or two later and the doctor missed the spot. It's just not easy to do. So even though we're going through and talking about all of these different methodologies and people get all hung up on the technology, it's fascinating technology, but it's really the doctor who's aiming the technology that's going to determine the outcome. Kind of like a professional golfer: is he using a set of Titleist clubs or a set of Wilson clubs?  It's the golfer that wins the game, not the clubs.  We'll go ahead and just share a little bit about each of these different treatments because it's interesting.  So let's talk about HIFU, which has been FDA approved now.  This methodology allows doctors to fire an intense ultrasound beam into the prostate and destroy tissue.  My feeling looking at studies is that it has a little bit higher risk of erectile dysfunction.  It's a little bit less precise than some of the other methodologies. Unfortunately, I haven't found a go-to guy and that's why perhaps I haven't had as much experience with HIFU.  Some of the HIFU I've seen have turned out well that have gone to other physicians and others haven't.  Laser treatments are a pretty nontoxic approach.  They're very precise.  There's a doctor down in Houston named Walzer who has done a few of these.  Some of the patients have turned out well because of its precision.  I think the incidence of missing the target is higher.  One of the hard things about trying to do a good focal therapy is the doctor, in his mind, has to set a margin around this spot that they see on the scan.  The scan is not a hundred percent accurate, so you have to put a fudge factor.  So the doctors that put too small a fudge factor have a tendency to miss cancers, the doctors that put too big of a fudge factor tend to cause more erectile dysfunction.  So there's a balance.  Not only does a doctor need to be good at targeting, he also has to have good integrative thinking skills so he knows how aggressive to be and also how to pick his patients.  If I refer patients to a focal doctor and he treats every single one of them that makes me uncomfortable.  There needs to be selectively to make sure that they pick people that are likely to have good outcomes.  You say, well, why is that important? If it's a nontoxic treatment, can't they go back and do it again?  And the answer is they certainly can go back and do it again.  But it's a major emotional downer to go through all this process and undergo the therapy with hopes for cure and then find out it didn't work.  It's kind of like taking your car to the mechanic and it didn't get fixed the first time.  Why would you go to the same mechanic again if he couldn't fix it the first time?  So it creates all kinds of consternation and you want it done right the first time. So laser, HIFU, cryotherapy, these are probably the three most common approaches that I see.  Most of our experience has been with cryotherapy with a guy named Dr. Duke Bahn and the interventional radiologists up in Ventura, California.  He has patients out about 10 years and we've had good results with dozens of patients that have seen him probably over a hundred patients over the last 10 years.  His cure rates are good.  The rate of erectile dysfunction is probably around 15 to 20%, which is better than radiation, which is in the 40 to 50% range.  But it's certainly not perfect. 

Liz:      [09:58] So you just mentioned cryo.  Is this similar to when people get their warts frozen off? 

Dr. Scholz:      [10:05] It's the same.  It’s liquid argon, it's not liquid nitrogen like when they're having treatment for skin cancers, but they put probes into the prostate that are hollow and that circulates liquid argon, which is extremely cold, creating an ice ball at the tip where the cancer is and then they run more and water and thought freezing again thought and that kills the cancer cells. 

Liz:      [10:28] So you can kind of get an idea about how complex these procedures are and how important it is to really pick a doctor who's done a lot of these. 

Dr. Scholz:      [10:38] Yeah and that's sort of the frustrating thing because in the context of things, no one has done a lot of these, these are new technologies and you have doctors, you know, radiation doctors that have been out there doing this for 10, 15 years and HIFU was only FDA approved a couple of years ago, you know, laser has been around for a couple of years.  It's very new and there's no quality control.  So, selecting the doctor should probably be the take home message.  I guess the first issue is do you want to pursue this? Are you a candidate for this? And then if, so, who is the maven that you want to try and track down to roll the dice with. 

Liz:      [11:23] So, because you're leaving a section of the gland untreated and there isn't really great follow up about long-term studies. How are these patients followed up with, are their PSA is regularly checked?  Are they getting scanned? 

Dr. Scholz:      [11:38] Excellent question.  The methodology is very similar to what is used for patients who are on active surveillance.  So if you leave a piece of prostate behind, that individual could always get a new cancer in that viable prostate tissue.  So the patients have to be watched closely and that would be considered one of the disadvantages of focal therapy.  If people have a standard radiation or an operation they can have their PSA checked a few times a year and if they behave well they're done. People that have focal therapy need to have ongoing MRI scans once a year to make sure that nothing is coming back or no new cancers are appearing. 

Liz:      [12:18] You said there were some other types of focal therapies.  Can you talk a little bit about those? 

Dr. Scholz:      [12:23] The technology with these things are so interesting that I've seen patients get infatuated with them. Like you know, this is so sophisticated, it's just got to work. But it isn't that the technology doesn't work, it's targeting that’s the problem.  For example electroporation where they put little wires on each side of the tumor and then run electric current between them to electrocute the cancer.   Electroporation sounds kind of exciting and it is effective.  The incidence of erectile dysfunction seems pretty low, but getting those wires in the right place is not an easy process.  So the doctor, that might be a consideration for this guy named Gary Onik in Florida.  I have not used him personally, but Dr. Duke Bahn speaks highly of him and he's been in the field for a long time.  Another approach is photodynamic therapy.  A specific substance is injected into the bloodstream that concentrates in cancer cells and then they bathe the prostate in laser light and the cancer cells die as a result of this exposure since they have this photo-porphyrin substance that gets inside the cancer cells.  This was used to treat lung cancers and esophageal cancers.  A guy named Mark Emberton in England has published a study using photodynamic therapy.  The results in men that really had low grade cancers weren't that great.  It's pretty well tolerated, but many of the men still had persistent disease. Now there's a new treatment out called TULSA where they fire beams out of the urethra.  This goes in the penis and they fire from the inside out while under MRI surveillance, active MRI surveillance.  It sounds really good on paper because the ability to monitor what they're doing while scanning to get that precision is so important.  However, it's so new.  I haven't had any patients that have had this treatment yet and I think the doctors are still in their learning curve. 

Liz:      [14:29] So you mentioned a couple of doctors.  Are urologists the people doing focal therapy or are these radiation doctors?

Dr. Scholz:      [14:37] Just about anybody that wants to do this can jump right in.  So a lot of times it is urologists, Dr. Duke Bahn, however, is an interventional radiologist.  That's not like a radiation therapist, that's an imaging doctor.  Interventional radiologists are probably better at this because they're trained to look at scans, whereas urologists, as you all know, are trained to do surgery. 

Liz:      [15:03] Dr. Scholz, all of this sounds highly technical.  How can a lay person find their way through all this information and find experts? 

Dr. Scholz:      [15:12] Well, I'll tell you, focal treatment, you know, offers a chance for reducing the risk of erectile dysfunction.  But the challenge of finding a doctor that really knows what he's doing and can pull this off is incredibly difficult. I don't think focal therapy is for everybody. The type of men that I see going down this pathway are you know, above average problem solvers, engineers, maybe their physicians themselves and then they'll do a lot of research and they'll visit a lot of centers and they'll take their time. Taking time is reasonable because many of these men have what we call Favorable Intermediate-Risk and the chance of the cancer spreading within six months is trivial. There's plenty of time, but it's a lot of work.  Finding out who is good is not easy to do.  Even for me.  I mean we'll even take a look online and see how people are rating people or, you know, talk to support groups and find out if there's someone that's had a good track record with a string of guys.  But it is hard.  I mean, our own experiences when we find someone that's good at what we do, we just stick to them.  It's too difficult to know who is really good at this. 

Liz:      [16:23] So most people when they're about to research something will go to Google and they'll type in focal therapy for prostate cancer. That's what I did when I was researching for this episode and a couple of ads come up in the beginning and it's hard to decide if those are actually the best sources of information.  What do you think about that, Dr. Scholz?

Dr. Scholz:      [16:45] Yeah, that is part of the struggle of course. That's how you find out about people who are doing this.  People that are doing ads presumably are doing enough cases to support an advertising budget, so perhaps they have some practice doing it.  But that is really just a sales tool and that doesn't address that question: are we dealing with someone with real skills, a special capacity to be really accurate? Which is what this type of treatment requires.  I'm talking about accuracy.  Let me also mention one thing that hasn't been covered and that is the type of accuracy achieved with radiation therapy is what's really changed radiation over the last 10 to 20 years.  Old time radiation was very unfocused and quite dangerous, but modern radiation is like little pencil beams.  So radiation therapists are trained to target, this is part of their daily fare.  We've been working a little bit with the people at UCLA to use radioactive seed implants with Dr. Albert Chang and focused stereotactic body radiation with Dr. Mike Steinberg.  With little arm twisting and cajoling, the physicians have been willing to treat smaller sections of the prostate rather than targeting the whole gland.  It's a very unnatural thing for radiation therapists because the standard has always been to target the borders of the gland with a little bit of a margin around.  But radiation actually sets up well for this sort of thing.  I'm not aware of anyone else doing this right now, but we do have some preliminary results with partnering with UCLA in this function and it seems so far that they're doing a pretty good job. 

Liz:      [18:33] So because all of this is new and still in the research phase, Dr. Scholz and I will be keeping our eye on the future of focal therapy. Dr. Bahn, who Dr. Scholz mentioned earlier, also wrote a chapter in “The Key to Prostate Cancer” on focal cryotherapy.  It is chapter 10 and it's a really great resource if you'd like to learn more.  Also, another great resource is an article published by Peter A. Pinto in the National Institute of Health, which talks about all the different kinds of focal therapy and it compares them and talks about outcomes.  So that's something you can look into.  It is a little technical, but with a little time, I'm sure you'll be able to understand it. 

Dr. Scholz:      [19:15] Sorry, I apologize about all the high tech, complex information we share today, but the goal is to try and lead men towards less toxic treatment and avoid the problems that are associated with so many treatments that result in permanent erectile dysfunction and incontinence and all those other problems that we've heard about so many times. 

Liz:      [19:41] We’ll put a link to that article on our website, podcast.prostateoncology.com.  Remember to help us out by rating, reviewing and subscribing on Apple Podcasts and send any questions or topics to [email protected].