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 14 year old dog has been diagnosed with Prostate Cancer. The symptoms came on quite suddenly and the diagnosis was given by the radiologist. The next steps from the vet are to take a tissue sample through the aorta lymph?. This by itself can be dangerous for bleeding and sedation at his age. I aksed if they could treat the cancer, but said that they could not know how to. The xray showed a slight dark spot near his sacrum. The ultrasound evidently showed an enlarged prostate. They do not give him long. I am against the aspiration of the tissue. I have taken him into a acupuncturist who specializes in dogs, who has also given him an herbal antibiotic to treat what she thinks is an infection. This could be a secondary infection or just an infection alone. I am willing to do whatever is necessary holistically to help him but not prepared to do invasive surgery. Is there anything else that you could recommend that I could do? Thank you so much, Lisa McFadin
I am scheduled to have my 10 year old Yorkshire Terrier’s canine tooth removed tomorrow morning. He has also not been neutered yet, but did have an enlarged prostate problem recently for which he was given antibiotics. They seem to have worked. However, I have been advised to also have him neutered tomorrow to reduce the chances of him getting prostate cancer. He can also visit daycare and maybe I can adopt another dog is he is neutered. If I get him neutered this late in his life, will this actually increase his risk of contracting cancer?
Tks, Dr. Dressler
S. Ford
i have a 18 months male pomeranian with one testicle (the other did not drop). If it weren’t for this, i would not neuter him. But i heard that given one of his testicle did not drop, his chance of developing cancer is higher and so the vet said he should get neutered ASAP. any thoughts on this? does him having only one testicle dropping means that neutering him would provide health benefit?
Thanks a lot! E
Dear Ed,
I have dealt with testicular cancer in retained testicles. It is real and the information from your veterinarian is valid.
Best,
Dr D
[…] I just found a wonderful article of "why not to neuter your dog": Bladder and Prostate Cancer: Neutering Male Dogs Increases Risk […]
Dr. Dressler,
Thank you for publishing this! I have labs and train & compete in hunt tests with both dogs. Recently I read an article regarding the appropriate age to spay/neuter your dog. It was based on a university study and showed that unless there were behavior problems, that neutering your male dog increases several types of cancer. One being hemangiosarcoma. I lost the article and study, and would like to forward the information to my other training friends. Is this the same study I had read??
Thank you, I will be purchasing your book, and forwarding your blog to my friends as well!
Dear Jennifer,
here is one link on females (2.2 times risk of HSA)
http://www.ncbi.nlm.nih.gov/pubmed/3192450
I had another one but can’t locate it…a nice review..I will let you know if it pops up
Best,
D
Dear Jennifer,
I should clarify 2.2 times the risk in spayed females versus intact females-
D
Dear Jennifer,
there is a nice review you might want to check out. Google:
Long-Term Health Risks and Benefits Associated with Spay / Neuter in Dogs
written by Laura Sanborn…
Best,
D
After several months of progressive ataxia which led to many trips to the vet, meds., and therapies, I finally slapped down the $1,000 for a CT scan of my 8 year old spayed mixed breed. The diagnosis was a tumor in the C7/T1 vertebrae…..right where I’ve been putting the Frontline all these years.
Coincidence? Perhaps.
We sent the CT disc to UTCVM in Knoxville, TN. The Oncology Radiologist concurred with the initial CT report. The tumor is inoperable. It would be difficult and expensive ($3,500) to perform a biopsy to confirm 100%.
The only thing that perks my dog up and enables her to get around for a few days is Decadron, oral every day, injections once a week. The injections are like a miracle drug. She’ll be almost quadriplegic, have an injection and in 3-4 hours be up on her feet although the signals just aren’t getting to the hind legs too well. The shots seem to give her about a week’s worth of mileage until she’s down again.
I hate to use such high doses of steroids, but it’s palliative care until we have to make the much dreaded decision that her quality of life is all gone.
Again, the bone tumor is right where the Frontline was put pretty regularly for years. Hmmmmm……………….
[…] Re: Spaying Totally untrue. Spay, Neuter, and Cancer: Revisiting and Old Trinity http://www.ncbi.nlm.nih.gov/pubmed/17516571 Bladder and Prostate Cancer: Neutering Male Dogs Increases Risk […]
Marie, please don’t feel guilty for neutering your Samoyeds. I lost my male Samoyed (that was never neutered) at age 8 to cancer. The doctor attempted to remove his spleen, and he ended up passing away the same day as the operation. The doctor said his body was full of tumors, and that even if he could have saved him, he wouldn’t have survived much longer anyway. I suspect that the cheap dog food with chemical preservatives that he ate for all of his life may have been to blame.
I have been much more cautious with my current dog, a Chinese Foo – (rare large breed dog). I thought I was safe with Nutro’s Natural Choice until I noticed during the first big dog food scare a few years ago, that even they had recalls on one of their products. I immediately started researching online and found a far superior brand of dog food made only with human grade ingredients.
My dog is noticeably more active since I switched. He is 12 years old now, but he plays and rolls around like a young pup. There’s a very good video exposing the dog food industry at PetFoodBasics.com. You’ll also learn what those pet food labels really mean, and you can order healthy pet foods, etc. from that link also.
I have an 11 year old Golden Retriever that has been diagnosed with prostate cancer. He is unable to urinate or defecate and we are trying to determine if we should try chemotherapy or euthanize. Everything I read about the prognosis for dogs is bleak and we are leaning towards euthanizing our beloved friend. Do you have any recommendations or opinions? Other than the diagnosis he is happy and in good health.
This is one where you should carefully consider the statistics available to you. Prostate cancer at this stage is fairly advanced and most often does not respond well to chemotherapy. It is time for life quality analysis. Take into account what the average life expectancy is for your breed and what the expected outcomes will be from treatment. Being unable to urinate and defecate are life quality issues. I will go into more detail in this month’s webinar because your question is a good one:
Dr D
Hi, Dr. Dressler! My male German Shepherd,almost 7 y.o., is spotting blood, but usually only after gets up from a nap. The vet also said that his prostate is “huge”, the ultrasound showed some sort of a growth between the prostate and the bladder. The vet recommended to neuter him and see if the growth disappears, along with shrinking of the prostate. I am not sure about the neutering, so is there anything alse I can do to shrink the prostate? The lymph nodes within that region are “clear”, and the vet said that the growth is most likely benign. Thank you.
Nataliya,
This is a very good question. I will answer it on this month’s webinar:
Be careful with recommendations that are not based on actual data (like the one you presented). You need to get the mass checked!!
Dr. D
Thank you Dr. Dressler. I will check them out.
Has there been any proof of nutritional supplements, etc. that help prevent cancer in dogs? Thank God, neither of my boys have cancer.
The last 2 labs I had, one I lost at 10 to leukemia (starting limping off and on – the vet thought he was bleeding through the bone, went down hill in a matter of days, I had him put down the day we received the diagnosis, less than a week before he was going over agility jumps and retrieving birds no problems seen), the other diagnosed with hemangiosarcoma the week of him 13th birthday).
I used to work at City of Hope as a nurse, and have seen way too many people with Cancer. I can only say bless you for working with animals with cancer. It is hard work dealing with sad cases day in and day out.
Again, bless you.
Jennifer
Hi Dr. D,
I just lost my two boys, Samoyeds in 2008. Both eleven, both neutered at age six. The first developed hypothyroidism after being neutered, basically a year after. Then at age 10.5 developed prostatic adenocarcinoma. I firmly believe that neutering played a role in this, what is your opinion? My other developed Diabetes Mellitus a year after being neutered. He passed from Ketoacidodis. No one wanted to help my guy with the cancer really. They just wanted to end his life. I am in a Master’s Biology program now and hopefully off to a Vet school after that.
Thank you
Marie
I have an 8 year old english bulldog, ever since little he’s had health problems such as dry eye, skin problems but nothing serious. He has started spraying inside the house, Im thinking about neutering him to avoid any further health complications as he gets older.
Help!
Thanks
Maria,
you need to get him to a vet to make sure there is nothing wrong with him…eight years old is a little old to start marking behavior, so I worry about medical problems..
D
Hi Dr. Dressler and Readers:
I would appreciate future info on Frontline’s connection to cancer. I will no longer be applying Frontline or giving heartworm meds to my 9 yr old Golden Retriever, Luke. His full brother, Mack, now has a brain tumor (obviously he no longer gets vaccines or other preventative meds.) Maybe no link, but why increase Luke’s chances of tumor/cancer. It is just another form of poison I will no longer be giving my Boys.
Thank you, Dr. Dressler for all you do,
Karen Bender
My vet isn’t in until 10am central time, so I wanted to ask here. I recently got my 4 month old puppy neutered. The first 2 days he was just fine when it came to going out and going to the bathroom. This morning, he seems to be having an issue with bladder control. He went outside and urinated like always, came inside, urinated, urinated on the steps to the basement, and then also ran to jump up on the soda, and urinated on that. Now normally he has been great with going outside. So I am worried there is an issue. He’s been taking his antibiotics, and his stiches look fine, there’s no redness around the site to indicate infection.
Hi,
my dog died yesterday of bladder cancer and I am devastated. He had previously had a perineal hernia, caused by an enlarged prostate that made him strain, and last April he had an operation on the hernia and was neutered at the same time. Could that neutering have made him more prone to get the cancer just in that short time?
I wish now I had now regularly given him Frontline, having read that it is thought that it might cause bladder cancer in dogs.
Julia
Julia, cancer is not caused by only 1 thing. Several things all add up, then it develops. I do not believe the neutering caused the cancer in your dog.
Sending you sympathy in this hard time of loss.
D