Prostate Volume Estimated From DRE Can Be Extremely Inaccurate

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My urologist has estimated the size of my prostate as 40 mL based on a DRE.  Recently, my general practitioner had me undergo a transabdominal ultrasound.  The results from that imaging study shocked me.  My prostate size according to the ultrasound is 145 mL!!?  I questioned my GP and he said that estimating from DRE is inaccurate.  I questioned my urologist and he agreed.  But my uro had told me that the size of my prostate was similar to a small lemon.  The ultrasound suggests it is more like a large orange.  At any rate my GP met up with the radiologist to look at the images again and they came to the same conclusion - namely that 145 mL is correct.

I am very upset with my urologist. Although I realize that a DRE is a "coarse" procedure for measuring the prostate volume, a difference of over 350% is outrageous in my mind.  If the accuracy is this poor, then urologists should not provide PV estimates via DRE; but should instead use ultrasound (TRUS is the standard, but according to my uro, doesn't work well if the prostate is bigger than 100 mL).

The urologist and GP kept trying to tell me that it is the transition zone which is important and the overall size is not that important.  Okay, but my point to my urologist is that having such a large prostate can remove potential treatment options from consideration. For example, TURP is only recommended for prostates 100 mL or less in size.  He begrudgingly agreed on this point.

I am now on Avodart in an attempt to reduce the prostate size and my symptoms (which are moderate although I am having an increasing number of short lived acute urinary retention episodes).

The point of this post is to not trust the PV estimated from a DRE.  Instead insist that your urologist conduct an ultrasound study.  I meet with my new urologist this coming week.

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  • Posted

    Personally, I've never heard of anyone trying to estimate gland size by a DRE nor how they could.

    I've had both ultrasound and MRI of my prostate.  With the ultrasound the uros would say it is 'about / approximately' x to y cc. (+/- 20%). With an MRI and an experienced radiologist, the volume estimates should be much more accurate, but still within a reasonable margin of error due to the abnormal shape of the gland.

    As for the transition zone statement - I would suggest you research that a bit. While it is my understanding that statistically the majority of lesions are found in that area - to me, that was sufficient reason to have an MRI and an MRI guided biopsy vs poking random holes in my body.


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  • Posted

    I would have to agree that your urologist wasn't even close.  Some urologists have a sense of size after doing many DREs.  Your doctors are right that size and symptoms don't correlate.  Some people can have BPH without obstruction.  Others can have a smaller prostate with more severe symptoms.  

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  • Posted

    If you have BPH size does not matter as you have to make a decision what you are going to do, Medications and supplements will not reduce the prostate to an acceptable level.
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  • Posted

    My urologist suggested Avodart/dutasteride but I declined.  A Google search brings us:

    [Image result for avodart side effects]

    Common side effects of Avodart include:sexual problems (such as decreased sexual interest/ability, decrease in the amount of semen/sperm released during sex),

    impotence (trouble getting or keeping an erection),

    testicle pain or swelling,

    increased breast size, or.

    breast tenderness.

    If these matter to you, think twice.  I stopped taking Tamulosin for the same reason

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  • Posted

    Thanks for the responses.  All of you sound experienced enough to know that a DRE is inaccurate.  But for us newbies, especially when a uro provides an image (small lemon), it is not that obvious.  Had he only been off by a factor of 2 (80 grams as the actual for example), I wouldn't be irritated; but 350%.

    Finally, I did find some studies done in third world-countries comparing prostate size determined by TRUS versus DRE from experienced urologists.  The studies were done because ultrasound equipment is often not available to patients in third-world countries.  IIRC, none of those studies showed a difference in size of more than a factor of 2 (but in general, DRE did tend to underestimate).  It is possible that the urologists estimated higher than they might otherwise because they were part of a study.  S

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  • Posted

    My urologist just said it was smaller than he expected given my chronic urinary retention, a subsequent MRI pegged it at 40cc which given my symptoms was quite small. I think most Doc's would  agree that a DRE is subjective and should size estimates should not be relied upon. The utility of the DRE is not estimating the size of the prostate but in finding lesions, nodules, irregularities and other causes for concern...

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    • Posted

      "The utility of the DRE is not estimating the size of the prostate but in finding lesions, nodules, irregularities and other causes for concern..."

      I agree. Urologists should not provide a size estimate using DRE but should instead, at a minimum, conduct a transabdominal ultrasound, which is quick and relatively easy.  TRUS would be better.

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  • Posted

    I had  generally 5 minute consultations with my original Urologist and I believe he didn't vary his process much. I find so many variations though on this site that leads me to suspect prostate treatment delivery in Australia, where I reside. My prostate story starts at age 47 (now 75) with just urinary voiding problems. Low PSA and moderate (DRE) prostate size. Age is important to mention on this site and perhaps sexual appetite can be useful to disclose on a future implication basis. There are many references here to "we are all different" and I keep switching from agreement to opposition to this thought process.

    While “we are all different” in regards to Prostates this should not be allowed to promote sub-standard, risky low cost treatments. We inherit different genetics that make us more or less susceptible to adversities under certain lifestyles and environments. Generally though a lot of our bodily functions are the same and mostly require “best practice” treatment. Glandular secretions and immune system responses circumventing danger and distress but can vary naturally or via drug induction. I was treated for BHP since 1990. Alpha blockers were introduced in 2006 and 5ARI (Dutasteride) in 2013. Both decisions took my former Urologist 5 minutes to make. Others here in Australia in similar circumstances were treated with the more expensive TURP surgical procedures. There appeared to be no reason for these differing decisions. All the other BPH treatments on offer elsewhere were just not mentioned here. For me MRI then identified 2 areas of PCa and Open Radical Prostatectomy in 2015. An earlier 6 hit U/S guided Biopsy in 2009 was negative. Another 10 hit biopsy in 2015 confirmed the MRI 3+4 Cancers. The other 8 U/S guided hits were found to be clear. This makes random U/S biopsies pretty useless without 40 or more hits. Can they really gauge the risk of spreading PCa via prostate biopsies on survival rates for pancreatic biopsies.

    Gleason 7s are difficult. Do you wait, have surgery, radiation or more drugs. Does a 7 become an 8 and so on over time. My Urologist told me a 7 progresses unless treated but I cannot find this covered elsewhere. He also said that subsequent cancers can be tested to determine if they are primary or secondary prostate cancers in their new location. I was told radiation could fuse my prostate to bladder making any eventual prostatectomy more complicated. Much of the theory around Alpha Blockers and 5ARI RISKS is relative to the differences between Gleasons. The wait and see 6s, then doubtful 7s and more concerning 8>10. If this is a progressive disease that doesn’t go away they likely all reach 10 in any case, if we live long enough.  This acceleration of the cancer makes use of the pathology examination in surveys and studies very dependent on timing rather that the real risk factor.

    Urologists had known since 1995 that alpha blockers would need an increase in dosage above 4m after 2 years. As no one had done the research 5 ARI (Dutasteride) was introduced. This took my Alpha intake to 8mg a day UNRESEARCHED anyway. Post-surgery incontinence, fungal infections, rashes and a mistreated blockage and months of self catheterisation has made my life miserable since. I couldn’t get past all this and then Polymyalgia Rheumatic (PMR). They don’t know what causes PMR only that the immune system increases the amount of inflammatory markers in the blood. It may be the body’s attempt to fight the cancer cells they say we have to assume we still have waiting to declare themselves. We are again prescribed drugs with dangerous “side effects” to reverse this process. While science knows so much there is still many body functions hidden and they seem to just take a punt too often.

    Drug trials always result in an amazingly high placebo benefit. Simply just the thought of being cured does something. The Australian government preferred U/S guided biopsies right up to 2015, possibly beyond. Urologists had known in 1990 that U/S didn’t detect PCa. I may have had Cancer as far back as 1990 or it may have come with my 5ARI drug. MRIs and PET scans have been around long enough for use in treatment scenarios or more importantly in drug trials. 5ARI drugs were trialled on U/S entry allowing the supplier that managed the trial to deflect serious PCa outcomes as relative to “study design. These drugs abnormally alter testosterone function to unnaturally manipulate cell growth which is similar to how cancer occurs. How the drugs affect men with different characteristics, different adversities and under different medications has never be assessed. When evaluating the risk vs benefit be sure to carefully consider the need and value of possible benefit and include Cancer, loss of prostate and the bits that go with it, incontinence etc. and quality of life in the RISKS.


    Prostates are difficult and BPH and PCa need far more research and data collection than is currently being done.  Best practice treatments are also being withheld due to Budget restraints. Currently it’s hard for us to decide what treatment, if any should be used and there’s no one without a vested interest to turn to. I failed to do proper research and partially blame myself for where I’m at but I feel I shouldn’t have had to do that myself with the fees healthcare professionals charge us.

    Barrie Heslop


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  • Posted

    Well, I went to my new urologist today.  Very good session.  He told me that he does not provide a prostate volume size to his patients based on a DRE.  Instead he provides a statement of "normal/big" for your age.

    His assistant gave me a bladder scan before I met with the uro.  After I urinated, he scanned me.  Reading was zero.  You can bet I didn't believe that.  He did it several more times and still got the same reading.  He was using the BVI 9400.  Then he brought in another machine (also a BVI 9400).  Still got zero.  That was it and I met with the new uro.

    While talking to the new uro, I mentioned that I had a bladder scanner and that while I am a novice at using it, I've never gotten a reading below 85 mL.  He looked at the readings his assistant took and didn't believe them either.  He conducted a scan on me and got a number of 68 mL.

    In my opinion, you should question results when you feel they need to be questioned.  I'm now in the process of scheduling a TRUS with my new uro.  I still am questioning the 145 mL prostate volume especially since my PSA is only 2.9.  A PSA density of 0.02 is very, very low.   The 40 gram DRE estimate is  undoubtedly low, but I also think the 145 gram might be high.  We'll see.

    Many of you might think I am being obsessive (my wife does too).  However, my goal is to "baseline" my current condition so that I can refer back to these numbers five/ten years down the road.  In my opinion, quantitative data is a good adjunct to qualitative or anecdotal data.

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  • Posted

    Just thought I would post a followup prostate volume measurement accomplished by TRUS:

    Digital Rectal Exam Result: 40 mL

    Transabdominal US Result: 145 mL

    Transrectal US Result: 99 mL

    Wouldn't mind an MRI result, but uro won't approve it. 

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