Half of long-term erectile function loss after brachytherapy is due to aging

Allen, you said that "...the gradual long term decline" (but of only an additional 10% in the SBRT case) was due to aging, not treatment."

However, the abstract from the BT report you reference say:  "Comparisons of the 5-year age-related and treatment-related EF decline show that 50% of the long-term EF decline is related to aging."

50% due to aging.  Are you seeking to imply that the other 50% of the long term EF decline is NOT BT treatment related?  I would believe that article's title would be quite dramatically different if this was the case; perhaps something like, "BREAKTHROUGH DISCOVERY!  BT/Radiation Therapy for PC no longer causes erectile dysfunction in men!" 

You're in touch with the authors...suggest they change the title!

clocknut said...


But, that kind of thinking had nothing at all to do with my mindset going into, or choosing, surgery as my treatment option. Rather, I was feeling pretty much invulnerable and bulletproof, and quite confident that loss of sexual function would be, at most, a very temporary situation.

@Clock: Well stated and understandable. Hence the need to inform newbies to take their time, consider the alternatives and think about all possible consequences.

@TA: Another like. Yes, the data WAS clear in that where there was a decent sample size the BT folks ALWAYS had better EF than the surgery folks. That is consistent with many QOL studies. Also, I'll point out that this study looked at 2 years post-procedure - which is the benchmark that most QOL studies use for stabilization for radiation SE's.

@Halbert: Feel free to rant if you like...

@RCS: I don't think that Clock was offended by my use of the term "rationalization". We all do it (at least I do). Anyway, he and I go way back and as I said - if I offended him in any way I am certainly apologetic about it.

@Everyone: Anecdotal info is usually interesting, sometimes helpful but rarely definitive when compared to larger group studies.


Jim

Tall Allen said...
I'm certainly not saying that there is NO treatment-related effect on ED.

Gotcha, thanks.  We agree.

Also, I agree with your statement (InfoLink) that the conventional wisdom is that radiation erodes potency slowly over time. 

But just to be clear, one should not presume that this conventional wisdom has been shown to be incorrect, although it is incomplete.  The Keyes report adds completeness to this conventional wisdom by highlighting that BT erodes potency slowly over time at a slower rate than aging erodes potency, amongst older men.  Some of the various rates of degradation for both aging and radiation treatment-induced are quoted, or as you summarized above, "only half of the total deterioration is due to treatment."

I would suppose that the age-induced ED rates, which was pulled for this report from other studies elsewhere, is now appropriately to be "subtracted" from all of the treatment forms for the same degree of "completeness"...?  Or is it generally accepted/known that as the population of men age an increasing percentage will get ED from natural aging processes?  I kinda thought it was known/acknowledged, which is why I'm not so quick to discard the basis of the existing conventional wisdom.  The next thread headline might read, "One-third of long-term erectile function loss after RP is due to aging," except that I think we already kinda assume this to be the case.

Norm said...
I would suppose that the age-induced ED rates, which was pulled for this report from other studies elsewhere, is now appropriately to be "subtracted" from all of the treatment forms for the same degree of "completeness"...? Or is it generally accepted/known that as the population of men age an increasing percentage will get ED from natural aging processes? I kinda thought it was known/acknowledged, which is why I'm not so quick to discard the basis of the existing conventional wisdom. The next thread headline might read, "One-third of long-term erectile function loss after RP is due to aging," except that I think we already kinda assume this to be the case.

You have to understand the pattern of erectile function loss after RP. It is quite different. There is a monumental immediate loss of erectile function after surgery followed by some recovery by the 2 year mark. I cannot say whether the 35% who retain functional erections after two years would then follow the same age-related decay. I would assume so, but my guess would be from 2 years post-surgery onward almost all of the erectile function decline would be age or co-morbidity related.

The conventional wisdom that radiation erodes potency slowly over time implies that there is steady continued degradation due to treatment. The authors say that is not the case - the degradation due to treatment occurs early (but not immediately) and then tapers off. The degradation due to aging increases with time, of course. Therefore, the claim that one has to look for the ED effect of radiation over a long time frame (like 5-10 years) is disproved by their analysis.

What men choosing one treatment or another on the basis of retained erectile function care about is the treatment-related decline, not the age-related decline. That's why this study was so important - it separated those effects. I think their methodology could be improved by using the EPIC database and by including the effects of other ED-related factors. That could only make the treatment effects account for less of the total loss.

- Allen

TA, where does the "35% who retain functional erections after 2 years" come from? Everything I've seen, and been told, puts the number much, much higher than that. Does that include those on HT and those who lost 1 or both nerves in surgery? Let's be very careful with the use of statistics.

"A fear of statistics will keep you average." -- Einstein

Sure, half of the long term erectile function loss is due to aging. But, the other half isn't. No treatment leaves you unchanged.

From the data I noted the loss rates for surgery are higher.

And I'd be lying if I said I didn't miss it every day. :-(

PDA, shall we start calling you "Hans" or "Franz?"

Not meaning to hijack this thread but Yooper really got my attention when mentioned "stents". Reminds me of the stent inserted during my recent ureteroscopy back in July of last year. I know that was necessary but WOW, what extreme pain when taking a leak while that little rubber/plastic thing is still in the ureter. Was installed on a Wednesday and the VA Urologist advised that I can remove it by myself on the following Saturday. Now that little gadget had a long black string attached to the bottom of it and the top part (of this "J hook stent) was hooked directly into the kidney. Merely pull the string to remove this stent and the string is available right out of the old peewee. Sounds painful but was really extremely easy to do, in fact my wife did the pulling of this thing. And now I will be getting a duplicate procedure on March 6th. Not really looking forward to another stent on this second one but it may just be necessary so the ureter doesn't close up on me.

Hey halbert, my comments were not aimed at you! Got what you're sayin'.

Bob - FWIW the stents we make are primarily venous, arterial and brain - so don't blame me for what you went through, YIKES! (:

halbert said...
TA, where does the "35% who retain functional erections after 2 years" come from?

I gave a link in the article. It comes from the largest, multi-institutional survey of the subject done to date, which you can read here:

Prediction of Erectile Function Following Treatment for Prostate Cancer

The study said...
The ability to attain functional erections suitable for intercourse at 2 years after treatment was reported among 177 of 511 (35% [95% CI, 30%-39%]) men who underwent prostatectomy.

The prostatectomy group included a small sample (8%) who did not have nerve sparing. The erectile function preservation among those who had nerve sparing was 37%, and was 13% among those who did not. None were on ADT.

The external beam radiotherapy group included 31% who had neoadjuvant ADT. Erectile function preservation was 44% if they did not have neoadjuvant ADT, and was 20% with it.

The brachytherapy group included 6% who had adjuvant external beam and 6% who had neoadjuvant ADT, but this did not make a statistically significant difference in erectile function at 2 years, probably owing to the small numbers who had those. Incidentally, in the Keyes et al. BT study, 44% also received six months of ADT.

I don't doubt that there are some surgeons who get better results. However, there is a lot of over-promising going on among urologists. Even with famous surgeons like Eastham and Scardino, only 43% got "back to baseline" with ED meds, only 22% without them.

Back to Baseline: Erectile Function Recovery after Radical Prostatectomy from the Patients' Perspective

- Allen

added MSKCC study

Post Edited (Tall Allen) : 2/25/2015 11:02:58 AM (GMT-7)

TA,

Thanks for posting the link to the Back to Baseline study. I feel that the important conclusion for newbies over 60 y.o. (and that's a lot of the guys you see on HW) is:

"Only 4% of men who were ≥60 years old with functional erections pre-surgery achieved BTB EF." BTB=Back to Baseline.

To me, this means a guy over 60 years old has a 96% chance of never getting his erectile function back to his pre-surgery baseline. I had guessed that for old guys it was a high number, but not this high. I would guess this is due to the damage done by surgery coupled with the damage due to the ageing process.

Thanks.

Norm,

I agree with Jim. You took my words out of context to claim the opposite of what I actually said. You completely misinterpreted it. The operative word in the sentence you quoted was "seem." The gist was that the potency didn't vary much between treatments only because age was not accounted for. Once age is accounted for, potency following radiation is always better than for surgery.

To your other point, as you can see, taking out the small non-nerve-sparing surgery group only increases the potency retention from 35% to 37%. Not a clinically significant difference.

- Allen