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Featuring Demian Dressler, DVM and Sue Ettinger, DVM, Dip. ACVIM (Oncology), authors of The Dog Cancer Survival Guide

Bladder and prostate cancer: neutering male dogs increases risk

Updated: June 5th, 2019

Oh man. This is going to make a lot of people in my field angry.  Apologies to classmates and veterinarian friends!

I came upon this 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.

Here is the study abstract.  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 over 3 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 eight times.  This is huge!!  Major, major, industry-shaking information, or it should be.

So what does this mean to you are considering castration of your dog (or he is castrated)?

Here are some overall statistics: Roughly 1 in 3 dogs will be affected with some form of cancer, and approximately half of those will die of it, at least based on the treatments that have been available up to this point (I believe we can do a lot better with what I call Full Spectrum Care).  Anyway, 1-2% of all cancers are bladder cancers, the most being transitional cell carcinomas (there are rarely other types of cancer that affects the bladder). So if we put all these above stats together and average them out, we are looking at a bladder cancer risk in castrated dogs of 2 percent.

For more helpful information and tools, get a copy of the Dog Cancer Survival Guide

Two percent is not a lot, but I neuter hundreds of dogs, and I see bladder cancer.  Two percent happens!  And the worst kind of cancer for your dog to get is…the one your dog gets, if you know what I mean.

Here is some information on bladder cancer in dogs.

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 before they opt for castration of male dogs.

And that is one of the purposes of this blog!

Best to all,

Dr Dressler


Leave a Comment

  1. Christine Taylor on October 1, 2018 at 4:07 pm

    There’s nothing wrong with my dog right now he is 10 and a half American Staffordshire Terrier which is a red nose pitbull he seems to be doing fine no problems but I just want to prepare for the future I feed him pedigree some people don’t agree and I do give him cook chicken breast for extra protein a lot of times I give him tablespoon of peanut butter sometimes and I sprinkle his dog food with granulated garlic my nephew came by and seen him and hadn’t seen him in over a year and he asked me what was wrong with him I told him nothing he said exactly he acts like he’s two years old instead of his age I started adding garlic to his food to help keep the flies and fleas away works great I got the idea from Springtime Incorporated wood sells garlic and vitamins for humans dogs and horses I also did not like using Frontline and those other products on my dogs in order to keep the fleas off garlic was a more healthier route and as you know is an antioxidant good for them and us also I am getting ready to take my dog in to get shots pretty soon hand have blood work done and everything to make sure he’s doing well I’m going to keep reading up and studying on how to keep your dogs healthy and so that way he can have a long life my other staffer he lived to be 14 and a half the one thing I want to know I know that milk thistle is a very strong antioxidant there is one more that is a little bit stronger than that and I can’t remember what that is right now so would it be okay to give my dog the milk thistle when he is taking garlic on his food everyday and I sprinkled the garlic on his food he’s feeding just like you would sprinkling salt on your plate of food any information give me I would appreciate it thank you oh yes I have heard that milk thistle is good to keep from getting liver problems for the dogs

  2. sell d4rksys cc on September 8, 2018 at 2:19 pm

    Wow that was unusual. I just wrote an really long comment but after I clicked submit my comment
    didn’t appear. Grrrr… well I’m not writing all that over again. Anyway, just wanted to say wonderful blog!

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