When you are about to perform an ultrasound exam on an animal, there’s always a quiet moment. A brief instant during which the world comes to a halt. Before you press the ultrasound probe onto the animal’s skin, you don’t know what you’ll find. Seconds later, all is revealed. It’s a big change in perspective. The way we see and approach the case changes as soon as the ultrasound is performed. And that short moment beforehand sometimes seems to last forever.
I was having one of those moments. What was going to appear on the screen this time? It was time to perform an ultrasound on the prostate of a 7 year old Golden Retriever. His owner had originally brought him to us for a spermogram (an evaluation of the quality of his semen). The results weren’t good. So it was time to move on to an ultrasound exam of the prostate.
The picture of white and grey spots appearing on the screen brightened the dark room. I had seen this image so many times. I had no doubt. I turned to the students who were following my consultations on that day to share my findings with them.
“Ok guys, so you can clearly see the prostatic parenchyma here. Look at its size, there is definitely prostatomegaly. And you can also see this pattern of hypo and hyper-echoic areas on… “
I caught the look in the owner’s eyes. She opened them wide, intrigued and a little scared by my description. It’s a bad habit that we have as veterinarians – using our own technical language that means nothing to the rest of the world.
I realised my mistake and started explaining what those complicated terms meant. “It means that your dog’s prostate is bigger than normal and…” but I couldn’t finish my sentence. Tears appeared in her eyes. “Oh no…”, she gasped. She was terrified. “Are you telling me he is suffering from prostatic cancer?”
It wasn’t the first time I had heard this comment. In fact, I’m still hearing it on a regular basis. If “it's bigger than normal”, most people automatically make the association with cancer. I remember reading somewhere that cancer today is the leading cause of mortality in adult dogs. So being afraid of it is totally normal.
However, it was the prostate I was looking at in this animal. In an entire male dog. And that makes all the difference when it comes to interpreting these pictures on ultrasounds.
I used my most reassuring tone and told her “Don’t worry”. I froze the ultrasound screen and pointed my finger at the structure I was describing to the students. “This,” I said, “is what we call Benign Prostatic Hyperplasia. This is no cancer.”
I think hearing me say the world “benign” automatically made her feel better. And she was definitely relieved when I told her it was not prostatic cancer.
But why was I so sure? It’s because Benign Prostatic Hyperplasia is THE most common prostatic disorder encountered in entire male dogs. By far. In fact, 80% of dogs more than 7 years of age have benign prostatic hyperplasia. It is almost a “normal” enlargement of the prostate that develops with aging and is caused by the effect over time of the sex hormone testosterone.
Prostatic cancer is in fact very rare in dogs (around 3% of the animals with enlarged prostates). Moreover, we know that in dogs, testosterone does not play a role in prostatic cancer development. In fact I would usually suspect prostatic cancer if a dog had a large prostate AND was castrated.
Could the Benign Prostatic Hyperplasia explain the poor semen quality we observed in this animal? Yes, definitely. Prostatic fluids represent close to 90% of the volume of the male dog's ejaculate. If the prostate is abnormal, the prostatic secretions will also be affected. And the semen quality can be impacted. Prostatic disorders are a cause of infertility in male dogs. And we believe their importance is underrated.
Benign Prostatic Hyperplasia is caused by testosterone so the best way to treat it would be... to remove the source of testosterone. But most owners would frown at me if I said that and reply : “Come on Doc, your suggestion to treat the problem in a breeding stud dog… is castration”.
There’s no doubt that castration will help reduce the size of a prostate enlarged with Benign Prostatic Hyperplasia. After all, it will remove the testosterone that initially causes the problem. The great news is: there are medical alternatives. They can reduce the size of the prostate. Normalise its secretions. And restore fertility in certain cases.
That’s the most important take-away. When dealing with Benign Prostatic Hyperplasia, the most common prostatic disorder in entire male dogs, there are things that can be done and are worth trying if you consider the male to be a valuable breeding stud. Back in my Alfort Veterinary School days, I presented a study on recovery of fertility after medical treatment of prostatic disorders in dogs. In that study, fertility was recovered in 61.1% of the treated animals. That’s why, in my opinion, it’s always worth giving medical treatment a try.