Bladder and Prostate Cancer: Neutering Male Dogs Increases Risk
Dr. Demian Dressler is internationally recognized as “the dog cancer vet” because of his innovations in the field of dog cancer management, and the popularity of his blog here at Dog Cancer Blog. The owner of South Shore Veterinary Care, a full-service veterinary hospital in Maui, Hawaii, Dr. Dressler studied Animal Physiology and received a Bachelor of Science degree from the University of California at Davis before earning his Doctorate in Veterinary Medicine from Cornell University. After practicing at Killewald Animal Hospital in Amherst, New York, he returned to his home state, Hawaii, to practice at the East Honolulu Pet Hospital before heading home to Maui to open his own hospital. Dr. Dressler consults both dog lovers and veterinary professionals, and is sought after as a speaker on topics ranging from the links between lifestyle choices and disease, nutrition and cancer, and animal ethics. His television appearances include “Ask the Vet” segments on local news programs. He is the author of The Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog’s Life Quality and Longevity. He is a member of the American Veterinary Medical Association, the Hawaii Veterinary Medical Association, the American Association of Avian Veterinarians, the National Animal Supplement Council and CORE (Comparative Orthopedic Research Evaluation). He is also an advisory board member for Pacific Primate Sanctuary.
Updated: March 23rd, 2020
Oh man. This is going to make a lot of people in my field angry. Apologies to classmates and veterinarian friends!
I came upon a study from the August, 2007 journal Prostate. Probably not what a lot of us would be reading in our spare time, but I am busy with upcoming info products for dog cancer owners and I dig through lots of publications.
The short story is the following:
Data was gathered from North American Veterinary Hospitals on male dogs that had been neutered (testicles surgically removed, or castrated), to evaluate the trend that had been noted in some older articles that neutering increased prostate cancer.
Because if this were the case (and this is my comment, not the authors’), it would seem ethics demand that owners of male dogs were advised of this before consenting to neutering surgery.
Here is what they found. Hold your hats, folks:
1. Castration of dogs increases total malignant prostate cancer by EIGHT times for some prostate cancers (prostate adenocarcinoma). So the answer is yes, castration does increase prostate cancer in dogs (which goes against what I was taught).
2. Castration of dogs increases the most common type of bladder cancer (transitional cell carcinoma) by about FOUR TIMES. This is huge!! Major, major, industry shaking information as far as I can tell.
Okay, the pundit gallery will argue, but castration helps control the unwanted dog population, helps unwanted behaviors like aggression and territorial urination in undesirable locations, etc. Yes, yes, all true.
But, we must start informing owners of this, to use Al Gore’s phrase, inconvenient truth.
And that is one of the purposes of this blog!
Best to all,
Dr Dressler
Dr. Demian Dressler is internationally recognized as “the dog cancer vet” because of his innovations in the field of dog cancer management, and the popularity of his blog here at Dog Cancer Blog. The owner of South Shore Veterinary Care, a full-service veterinary hospital in Maui, Hawaii, Dr. Dressler studied Animal Physiology and received a Bachelor of Science degree from the University of California at Davis before earning his Doctorate in Veterinary Medicine from Cornell University. After practicing at Killewald Animal Hospital in Amherst, New York, he returned to his home state, Hawaii, to practice at the East Honolulu Pet Hospital before heading home to Maui to open his own hospital. Dr. Dressler consults both dog lovers and veterinary professionals, and is sought after as a speaker on topics ranging from the links between lifestyle choices and disease, nutrition and cancer, and animal ethics. His television appearances include “Ask the Vet” segments on local news programs. He is the author of The Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog’s Life Quality and Longevity. He is a member of the American Veterinary Medical Association, the Hawaii Veterinary Medical Association, the American Association of Avian Veterinarians, the National Animal Supplement Council and CORE (Comparative Orthopedic Research Evaluation). He is also an advisory board member for Pacific Primate Sanctuary.
My dog has a hard, peanut sized growth in his scrotum. He was castrated by my local vet 8 years ago when he was a pup. over the years his scrotum shrank. About a year ago I noticed that his scrotum was starting to sag again. I felt his scrotum and there is a single hard lump of tissue about the size and shape of a peanut. I know for a fact that the lump was not there after the surgery. Can anybody help? please e-mail me if you have any idea what may be going on with my boy. elliotwibley@yahoo.com
Dear Justin
go to your vet (or another one if you feel better) and get proper medical attention for your loved family member. Might be nothing, might be life threatening.
Dr D
We rescued two puppies from a large litter over 10 years ago. All 8 puppies were different and obviously sired by different fathers. We lost our little female of terrier dissent last Spring due to an autoimmune disease brought on by tick borne rocky mountained spotted fever. She had been under veterinarian treatment for two years but suddenly came ill again. After a couple blood transfusions, she only got worse and nothing further could be done to help her so we sadly had to put her to sleep, she was under 10 years of age. Her brother, whose father was obviously a golden retriever, is now sick and recently diagnosed with terminal prostate cancer so we are just keeping him comfortable and watching over him closely. Both dogs were spayed/neutered between 4 to 6 months as advised by our vet. We are so devastated and now question alot of things in the world of veterinarian medicine, vaccines, and other products (like frontline) that we faithfully gave to our beloved dogs to take care of them.
[…] not been spayed by their fourth heat run a higher risk for mammary cancer. (Spaying offers its own risks for other types of cancer, but that’s another […]
ps every g erman shepherd or guard dog breed i ever EVEEEEEEEEER met was territorial regardless its like.. hardwired into dogs Not their testosterone.
excuuuse(to the neutering lowers aggression and territorial behaviour bit) me but my first dog was neutered and he was the most territorial dog i ever met.. and he would growl so hard that u saw all his teeth, hated kids, hated men, didn’t hate us but bit us many times, he was a medium small dog like 40lbs but stalky for his height, a mixed breed tibetan terrier or lhasa apso type dog with some kinda terrier that the other puppies were all yellow and he was the one fluke that looked nothing like the rest that was very lhasa apso ish but he had a non pushed in muzzle and a very strong bite and teeth. also didnt’ like other dogs but didn’t bark at them or chase them.. he was just easily fearful of them.
Dear Dr D,
thank you for addressing the question, I realize that I’ve provided little to no information and it’s hard to give a proper diagnosis, but I needed to get a second opinion given the shocking stats you’ve provided on your blog. I do have some decision making to attend to. Thanks again !
With all due respect to Eve, I have to say that this personal opinion is entirely based on the benefits for the owner from having a dog neutered and not at the health benefits for the dog itself. Citing the names of dog psychologists doesn’t change the fact that this is not a well argued response from a medical point of view.
I myself have a 10 year old Rottie, which has never been disloyal, or aggressive and I’ve always been able to control him, regardless of the evident need to procreate when there are females in heat.
Now I stand with the problem of prostate hypertrophy and I still am not convinced of the need to have the dog castrated, even though the opinion of my vet is that there is a narrowing of the urinary, which increases the risk of prostate cancer.
Dr. Dressler, what is your opinion given the circumstances?
Dear artox,
altough this is a cancer blog I will address your question- when we are seeing decreased urethral caliber (width) due to BPH with also the start of difficult urination I will often advise castration…But I do not necessarily do it prior to having a narrowed urethra, nor if it is mild. I hope this helps
Dr D
thank you for your honesty and candor. Hopefully the almighty dollar will fall by the wayside, and this coverup will be exposed. Spread the news everyone. Put links on your facebook. Little Tiger deserves it.
Spay/neuter is BASELINE standard of care for all pet dogs. It’s bad medicine to advise a dog owner to keep their pet dog intact.
For REAL advice on dog behavior, and why neutering is essential to your dog’s longterm health and success as a pet, talk to REAL experts on the topic. For crying out loud.
Dr. Ian Dunbar (the inventor of puppy training and the godfather of positive dog training)
Dr. Patricia McConnell (the academic translator of dog behavior –the literal dog whisperer)
Dr. Karen Pryor (the backbone of clicker training, which is now the main tool used in precision training for complex activities on all sorts of species)
Dr. Bruce Fogle (author of “The Dog’s Mind” in which he explains the chemical process an unaltered dog must go through to control its body, all of the time, versus that of a castrated dog)
And even if there are valid risks, albethey minute, associated with neutered a dog, WE (dog professionals, Dr. Dressler) ALL TRULY KNOW THAT THE MAIN REASON TO NOT NEUTER A DOG IS THAT THE OWNER IS UNEDUCATED ABOUT THE REASONS THEY MUST NEUTER THEIR DOG.
Many, many, many, many more dogs die prematurely because they were not neutered than will ever die, or even become unwell, because they were neutered.
The torment that an intact male dog must go through, with his incredible sense of smell, knowing, his whole life, that there are ladies out there who need him…
Check out Craigslist “Lost Dog” postings some time. Or the flyers inside any vet clinic or shelter anywhere, in any community, in any region.
90% or more of the lost pet dogs, anywhere, are intact males.
80% of bites are inflicted by intact males.
The average dog in a shelter in any community is young intact male.
Bad things happen to boy dogs allowed to keep their testosterone.
They are testosterone drunk, unable to focus on anything, truly, other than the smell of that girl dog who walked by two days ago, or was maybe a mile away a few hours ago.
His sense of smell + testosterone drive = a fella with a lifelong case of blueballs, in constant torment, agitation.
Neuter your dog, and you will see that, suddenly, his loyalties are truly with you. His focus doesn’t have to be diverted, he’s, now, alive to be your pet, not to perpetuate his species.
You cannot have it both ways. You cannot allow a dog, whose focus and adoration you want, to have the drive to procreate. Or you will always be the second-most important thing.
And, besides, it just shows the world that you know enough to have a dog.
Get real, neuter your dog, and quit projecting your own insecurities onto a helpless, hormone-driven creature. Do your boy a solid and give him a break from the torment of anxiety-fueling testosterone.
Dear Eve
This is a blog on veterinary medicine, not behavior. If you spend a wee bit of time reading the Guide and the remainder of the posts on this blog you will see that there is rarely a time when a complex issue is treated as if it is one sided. This is one of those complex issues. I have approved your comment in this spirit, so guardians can see the polarized perspective and tone of your comment as one position to consider. And as to whom is considered “real” or a “dog professional”, I have little interest in the topic and doubt it matters to the thinking persons who read this blog.
Dr D
I am SO confused I read your article about Neutering increses bladder and prostate cancer…and in the comments below it…you are recommending it! I did not neuter my dogs, and I felt comfortable with the decision…too much controversy. I felt good with my decision reading your post, only to get confused with your replies ot comments!
Dear Dr. Dressler,
I have two Male Golden Retrievers ages 11 yrs. 8 mos. The vet is recommending that I have them neutered to prevent prostate cancer. One of the dogs in going in for sugery to have 2 Mass removals, 1 is malignate. The other is going under for a broken tooth. So he recommended that he castrate them while they are under. I would love your opinion on whether it is necessary at this age.
I look forward to hearing from you. thanks, Karen