prostatic enlargement in castrated male

Re: prostatic enlargement in castrated male

Richard Carter — Wed, 26 Feb 2014 17:39:14 GMT

thanks all - testosterone levels are back - no testosterone so will see how they feel about firocoxib.

Re: prostatic enlargement in castrated male

Gerry Polton — Fri, 21 Feb 2014 10:05:46 GMT

Hi Malcolm

I agree. When I first saw the Dawn Cooley paper (the rottie questionnaire based one) I was far from convinced by the confidence intervals stated for the relative risk estimates. However, further work has shown this risk to be real with considerably more dogs from a wide range of breeds. The biggest such study used the veterinary medical database in the US with over one million registered animals. The relative risk across all breeds was less than reported in the Cooley paper but the confidence in the relative risk estimate stated was greater. Neutering has been shown to increase risk of many other cancers too though perhaps less reliably including haemangiosarcoma, mast cell tumour, lymphoma.

Gerry

Re: prostatic enlargement in castrated male

Malcolm Ness — Fri, 21 Feb 2014 09:43:34 GMT

[quote user="Gerry Polton"]Early neutering increases the risks of osteosarcoma in large and giant breeds approximately twofold. In rottweilers specifically we know that the increase in risk is greater: approximately 3.2 for females and 3.8 for males. Prostatic carcinoma is more likely, as previously noted, to the tune of an approximately fourfold relative risk (but only in males )[/quote]

Has there been some more recent work on this Gerry? When I looked at it a number of years ago, the claims that were being made (and widely propagated) appeared to come from a single source paper and while that paper certainly made a claim, the data presented were less than convincing. I guess I am questioning whether or not this is soundly based information or just another scientific urban myth.

Re: prostatic enlargement in castrated male

Gerry Polton — Fri, 21 Feb 2014 09:33:58 GMT

While I love to cogitate on such philosophical issues and the role of the profession at large, my responsibility is for the patients under my care. Granted responsibility for individual and population health are not mutually exclusive.

Gerry

Re: prostatic enlargement in castrated male

Mark Holmes — Fri, 21 Feb 2014 09:29:07 GMT

[quote user="Gerry Polton"]

Essentially, yes. In fairness, his pitch, as I recall, was slightly more rhetorical than you and I have written, along the lines of: we will never resolve this problem until all cats and dogs are neutered before reaching the age of procreation.

[/quote] Philosophical point but is population our responsibility or is health? If the two are not compatible what should be a Vet's priority?

Re: prostatic enlargement in castrated male

Bob Russell — Fri, 21 Feb 2014 09:13:01 GMT

Not checked the thread thoroughly but the Rottie study (from memory) was based on surveys rather than clinical study.

If this is the case did they take other risk factors into account? Many/most neutered rotties tend to be moderately to extremely overweight. Assuming trauma has a place in development of bone cancer was this taken into account, I wonder?

I don't go for early neutering of male dogs (except for the highly troublesome ones). Larger breeds tend to be around a year if possible.

I don't push owners into castrating dogs, unlike spaying of bitches. Most of my clients are fairly responsible!

Re: prostatic enlargement in castrated male

Gerry Polton — Fri, 21 Feb 2014 08:26:23 GMT

Re: prostatic enlargement in castrated male

Mark Holmes — Thu, 20 Feb 2014 19:54:05 GMT

Gerry - are you saying the RSPCA director said owners should not be given the choice about neutering or the age if neutering? Did he draw a distinction about males and females?

Re: prostatic enlargement in castrated male

Rob Loxley — Thu, 20 Feb 2014 19:27:00 GMT

[quote user="Gerry Polton"]based upon a total of four cases!!![/quote]

I looked up the Schneider paper which gave the 0.5/8/26% statistic and it suggested 87 case-controlled matches? I didn't however realise that the statistics just referred to malignant mammary neoplasia: I'd suggest we see a whole load more benign than malignant mammary tumors?
The recent JSAP review concluded that good evidence on this subject is somewhat lacking.

[quote user="Gerry Polton"]What about removing ears on white cats...[/quote]

I think with the potential problems we need to assess the morbidity/treatability to give good advice: OSA and PCA are pretty dead end; USMI can be a longterm expensive PITA, whereas SCC of the pinna is usually curable (no?), and BPH eminently treatable.

Re: prostatic enlargement in castrated male

Martin Atkinson — Thu, 20 Feb 2014 18:31:45 GMT

[quote user="Richard Carter"]well we do it quite deliberately in cattle to get a bigger build[/quote]Isn't that just to get more fat and better marbled meat rather than an actually greater height and not wasting energy being well....males!? But any road up you're talking about producing androgenous beasts for meat production.

In a dog I'd have thought that any spurious notion that they will continue growing if the growth plates don't close is far outweighed by failure to gain male growth potential stature and muscle up due to loss of testosterone. I've seen a hell of a lot of dogs in 38 years of practice and counting and I don't think I've ever been aware of one that had grown bigger because it was castrated. And in cats which are routinely castrated I recommend leaving them to near puberty to encourage them to grow into stronger cats.

Re: prostatic enlargement in castrated male

Gerry Polton — Thu, 20 Feb 2014 18:29:17 GMT

I am really enjoying this thread and learning a good deal. Thanks for the abstract about growth plate closure, John.

At BSAVA Congress in 2012 there was a panel discussion about the risks and benefits of early neutering. There were pitches from an oncologist, a soft tissue surgeon, a behaviour specialist and the hospital director of the RSPCA clinic in Greater Manchester. It was a truly fascinating discussion and the audience participation really made it into a great session. I will try to summarise the points without trying to bias you towards one decision or the other but I will definitely finish by stating what surprised me the most and what I have done about it to try to contribute to our collective education.

For the sake of clarity, early neutering was agreed to mean neutering before one year of age or thereabouts. Initial discussions led to a realisation that what was considered early by one specialty was not suitable for another.

Oncologist: Early neutering increases the risks of osteosarcoma in large and giant breeds approximately twofold. In rottweilers specifically we know that the increase in risk is greater: approximately 3.2 for females and 3.8 for males. Prostatic carcinoma is more likely, as previously noted, to the tune of an approximately fourfold relative risk (but only in males ). Removal of organs or appendages definitely reduces the risk of cancer developing within them, however, would you present your husband or wife or child for elective organ removal for that purpose...? Don't answer that. What about removing ears on white cats... It is true that ovariectomy reduces the lifetime risk of mammary neoplasia. However, the data, from 1969, from which the statistics that we have all learned (in fact the only statistics that some of us learned from five or six years at veterinary school) are, shock, horror, based upon a total of four cases!!! Can you believe it! So, it is an accepted fact that neutering reduces the risk of mammary neoplasia, and it is accepted that it reduces the risk a lot. However, the oft-quoted 0.25% risk if neutered before first season, 8% if neutered before second season statistics should be taken with a pinch of salt/burned and forever forgotten* delete as appropriate.

Soft tissue Surgeon: Early neutering definitely induces urinary incontinence. It does it a lot and this is a lifetime condition which results in quality of life issues for patients and owners. Surgical and medical amelioration are possible but not always successful. There are types of dog which are at greater risk. Perhaps neutering decisions should be taken on an individual patient basis taking account of the risks of the various problems associated with neutering.

Behaviour Specialist: The most common cause for abandonment and early euthanasia is behavioural problems. There is an alarming burden of evidence that says that neutering at sensitive times in the emotional development of dogs and bitches is very directly associated with the development of fearful (and other) behaviour traits. To put this in context, more than 30% of all dogs in Australia that are euthanised in early adulthood are so because of behavioural problems. These animals are the ones which cannot be rehomed because of their behaviour problems.

RSPCA Hospital Director: There is an unsustainable burden of unwanted dogs and cats in rescue shelters. Not all of them are crossbreeds from a particular demographic. Neutering is the only way to resolve this problem. Owners should not be given the choice.

I cannot pretend to have got every detail exactly correct, but this is how I remember it. Of all of these expert opinions, I was most struck by the information from Dr Kersti Seksel, the behaviour specialist. The very fact that neutering actually induces behavioural problems like separation anxiety, destructive behaviour, fear aggression, and the window of their lives in which this behaviour was likely to develop was (I think) approximately 4-9 months of age (I may have got that wrong so please do not change any practice policies on the basis of this). I was made to recall some of the most distressing cases of separation anxiety in particular that I had seen in my general practice days and it really troubled me. And the problem is, this data just doesn't make its way into the widely accepted veterinary literature. So, I promised I would finish by saying what we will do about it. An internationally recognised veterinary specialist in animal behaviour has been commissioned to write a review on this very subject for JSAP. It promises to be totally objective and hopefuly absolutely gripping for everybody.

Gerry

Re: prostatic enlargement in castrated male

Rob Loxley — Thu, 20 Feb 2014 18:10:50 GMT

[quote user="Martin Atkinson"][quote user="Bob Russell"]Testicular tumours in dogs quite common (but fortunately most behave quite well). Anal adenomas common, benign prostatic hypertrophy (uncomfortable?) common.[/quote] Good points but testicular tumours are not common enough to be a reason to routinely castrate and benign prostatic hypertrophy and anal adenomas respond to castration if performed when necessary.[/quote]

My opinion is that prevention of BPH/prostatitis (which are eminently, easily treatable) nor testicular tumors (fairly uncommon and generally identifiable and successfully treatable) don't justify a blanket policy of chopping all dogs testicles off.
And if it's a rottie presenting, the increase (on top of an already higher) risk of osteosarc (and the morbidity of OSA) would make me very wary about castration without a good long chat.

Re: prostatic enlargement in castrated male

Alex Allen — Thu, 20 Feb 2014 18:05:34 GMT

Just found this article as well .....but what does it mean clinically?? Delay in closure vs extended period of growth??

J Feline Med Surg. 2014 Feb;16(2):149-56.

Effect of neutering and breed on femoral and tibial physeal closure times in male and female domestic cats.

Perry KL(1), Fordham A, Arthurs GI

The timing of physeal closure is dependent upon many factors, including gonadal steroids, and previous studies have shown that early neutering delays physeal closure. Pelvic and femoral radiographs of 808 cats were analysed and physes at the greater trochanter, proximal femur, distal femur and proximal tibia were recorded as being open or closed. Date of birth, gender, neuter status and breed of cases were recorded. Each physis was analysed individually at a specific age. The number of male entire (ME), male neutered (MN), female entire (FE), female neutered (FN), pedigree and non-pedigree cases at each of these ages was recorded. The number of cases that were open or closed at each stated age were compared between the neutered and entire, the female and male, and the pedigree and non-pedigree groups using a Fischer's exact test, with P <0.05 being considered significant. Seven hundred and eighty-three radiographs were included: 359 MN, 95 ME, 237 FN and 92 FE. Ninety-six cats were pedigree and 687 were non-pedigree. A statistically significant effect was shown with physes closing later in MN than in ME cats for the greater trochanter (P = 0.0037), distal femur (P = 0.0205) and tibial tuberosity (P = 0.0003). No effect was shown for the proximal tibial or proximal femoral physes, nor for any physis when comparing FE with FN cats. No statistically significant effect of breed or sex was noted. Physeal closure will occur later in MN cats than in ME cats for the greater trochanteric, distal femoral and tibial tuberosity physes, and the potential clinical consequences of this should be evaluated further.

Re: prostatic enlargement in castrated male

Alex Allen — Thu, 20 Feb 2014 18:00:48 GMT

[quote user="John Flynn"]I, for one, would be interested to hear your thoughts on the data suggesting this increased risk in castrated males and your thoughts on possible confounders.[/quote]

Various studies have looked into castration being a risk factor for urinary tract and prostate cancer in dogs. A population study done by Bryan, Keeler et al in 2007 showed castration increased the risk but the incidence rate in castrated dogs was 0.43% ... so it is (thankfully) rare. They also identified a genetic predisposition and breed association. This has also be suggested by work at Utrecht by Chen-Li Lai, Eric Teske et al (2002-2008). They identified a difference in androgen receptor location / density in castrated dogs with prostate cancer and one theory is that in genetically predisposed dogs the presence of testosterone provides an anti-tumour effect so once they are castrated the risk of cancer increases. Teske found castration increased the risk of prostatic carcinoma (OR=4.34) but age was also a factor and the onset of the PCA was not linked to a time point after castration.

Re: prostatic enlargement in castrated male

Tom Ward — Thu, 20 Feb 2014 17:52:36 GMT

It would be very interesting to hear other people's opinion on the necessity of canine castration - a poll is needed!!

Re: prostatic enlargement in castrated male

John Flynn — Thu, 20 Feb 2014 17:48:39 GMT

[quote user="Alex Allen"]I've heard this story before but as far as I'm aware the studies that have looked at bone density and growth plate closure have not found castration in cats and dogs significantly affects them.[/quote]

Root, M.V. Johnston, S.D. Olson, P.N. (1997) The effect of prepuberal and postpuberal gonadectomy on radial physeal closure in male and female domestic cats. Veterinary Radiology & Ultrasound. 38(1), pp. 42-47

"Abstract: Male (n=6/group) and female (n=6/group) kittens were gonadectomized at 7 weeks (prepuberally) or 7 months of age (postpuberally), or left intact. Lateral radiographic projections of the right forelimb were made from 4 months of age until the distal radial physis was closed, or 24 months of age. In males, distal radial physeal closure was delayed in both groups of gonadectomized animals, compared to intact males (p<0.01). In females, proximal radial physeal closure was significantly delayed in prepuberally gonadectomized animals (p=0.02), and distal radial physeal closure was significantly delayed in both groups of gonadectomized animals, compared to intact animals (p<0.01). Final radial length (females p<0.01, males p=0.01), and age and radial length at time of the growth plateau (p<0.01) were significantly increased in all gonadectomized animals. Age at gonadectomy had no effect on age and radial length at time of the growth plateau. No puberal growth spurt was observed in any of the cats."

Re: prostatic enlargement in castrated male

Alex Allen — Thu, 20 Feb 2014 17:41:28 GMT

[quote user="Martin Atkinson"]Out of interest I had some dickhead come in the other day with a runt of a dog he'd been sold, in a pub believe it or not given the other ongoing thread, as an Akita (well it had a curly tail and pointy ears!) and wanted it castrated because he'd heard that this would stop the growth plates from closing so it would grow taller. Whats with that then?![/quote]

I've heard this story before but as far as I'm aware the studies that have looked at bone density and growth plate closure have not found castration in cats and dogs significantly affects them.

Dogs are not recommended for osteoporosis studies any more as it has been realised that sex hormones don't affect their bones as they do in rodents and humans.

Re: prostatic enlargement in castrated male

Richard Carter — Thu, 20 Feb 2014 17:02:57 GMT

[quote user="Martin Atkinson"] it castrated because he'd heard that this would stop the growth plates from closing [/quote] well we do it quite deliberately in cattle to get a bigger build

Re: prostatic enlargement in castrated male

Martin Atkinson — Thu, 20 Feb 2014 16:41:33 GMT

[quote user="Bob Russell"]Testicular tumours in dogs quite common (but fortunately most behave quite well). Anal adenomas common, benign prostatic hypertrophy (uncomfortable?) common.[/quote] Good points but testicular tumours are not common enough to be a reason to routinely castrate and benign prostatic hypertrophy and anal adenomas respond to castration if performed when necessary.

I do not advocate routine castration in dogs as I see no advantage unless there are good behavioural or medical reasons to do it.

Out of interest I had some dickhead come in the other day with a runt of a dog he'd been sold, in a pub believe it or not given the other ongoing thread, as an Akita (well it had a curly tail and pointy ears!) and wanted it castrated because he'd heard that this would stop the growth plates from closing so it would grow taller. Whats with that then?!

Re: prostatic enlargement in castrated male

John Flynn — Thu, 20 Feb 2014 16:33:49 GMT

[quote user="Gerry Polton"]I wonder how many people would present their puppies for castration if they knew... I might start a discussion thread. Haven't done that before.[/quote]

Was v briefly touched upon in a thread as an aside (http://www.vetsurgeon.org/forums/t/16088.aspx?PageIndex=9)

I, for one, would be interested to hear your thoughts on the data suggesting this increased risk in castrated males and your thoughts on possible confounders.

Re: prostatic enlargement in castrated male

Bob Russell — Thu, 20 Feb 2014 16:17:07 GMT

[quote user="Gerry Polton"]

Hi Martin

Not a lot of people seem to know this but prostatic cancer is approximately four times more likely in dogs that are castrated at the usual age compared to entire males. In dogs the pathophysiology appears to be associated with hormone withdrawal in complete contrast to the usual story in human (entire) males.

I wonder how many people would present their puppies for castration if they knew... I might start a discussion thread. Haven't done that before.

Gerry

[/quote]

BUT a rare tumour multiplied by four is still a rare tumour, just not as rare!

Testicular tumours in dogs quite common (but fortunately most behave quite well). Anal adenomas common, benign prostatic hypertrophy (uncomfortable?) common.

Like it or not you have started a discussion!

Re: prostatic enlargement in castrated male

Gerry Polton — Thu, 20 Feb 2014 16:03:37 GMT

Hi Richard

I have never heard of a perianal mass as a source of testosterone.

If it was within budget, a high-quality abdominal ultrasound examination would give you more information on the prostate, the possibility of retained testes, adrenal gland anomalies and medial iliac lymphadenopathy if the perianal mass was a malignant hepatoid gland epithelioma/carcinoma.

Gerry

Re: prostatic enlargement in castrated male

Gerry Polton — Thu, 20 Feb 2014 16:00:44 GMT

Hi Martin

I wonder how many people would present their puppies for castration if they knew... I might start a discussion thread. Haven't done that before.

Gerry

Re: prostatic enlargement in castrated male

Martin Atkinson — Thu, 20 Feb 2014 13:16:01 GMT

I have also seen prostatic tumours in castrated dogs presumably these were most likely to be developing before castration but not all tumors would be testosterone dependent. One tested negative for the BNPE test so that is not reliable.

Be wary though. I had a dog that I castrated and I therefore am 100% confident that I removed 2 testes and it subsequently developed a prostatic cyst. When the prostate was surgically examined further it turned out to have a third abdominally retained testicle!!!!

Re: prostatic enlargement in castrated male

Richard Carter — Thu, 20 Feb 2014 11:28:15 GMT

My initial feeling after the prostate exam was a benign prostatic enlargement as well - the presenting sign was tenesmus with defecation attempts, not urinary tract problems. Am waiting for a urine sample - any thoughts on the peri-anal tumour being a testosterone source?

Hair coat is very good. Castration not done by us but am assured by the owner that he had 2 descended testicles before surgery and they are not there now.

Will look into testosterone level testing and see if it is in budget.

Thanks