Heartbreak for dog owners: Popular breed more prone now to cancer

HUDSON, Mass. — The American Kennel Club lists golden retrievers as the third most popular breed in the United States, just behind Labrador retrievers and German shepherds.

“Golden retrievers naturally love people,” said Pauline Hoegler, owner of Golden Opportunities for Independence in Walpole, which raises the breed to serve as help dogs.

And the feeling is apparently mutual.

“I think what attracts most people to goldens is their sweet personality,” said Alysson MacKenna, executive director of Yankee Golden Retriever Rescue in Hudson. “They just really, really want to make that connection with people. In my opinion, there is no sweeter breed.”

But it appears there is a genetic flip-side to that sweet disposition.

“Goldens are one of the breeds that we see that get a lot of cancer,” said Dr. Cheryl London, a veterinary oncologist and director of the clinical trials office at Tufts University’s Cummings School of Veterinary Medicine in Grafton. “For a period of time, there was a lot of interbreeding to create the golden retriever and all the other breeds. When you do that you create issues in the genes that predispose you to a variety of different things and one of them is cancer.”

In fact, several studies -- both in Europe and North America -- have shown golden retrievers develop cancer at far higher rates than most other dog breeds.

One study, published in the Journal of Veterinary Internal Medicine, looked at the cause of death in more than 72,000 dogs in North America by breed. It found golden retrievers ranked second on the list of 82 breeds for cancer deaths -- with at least half the goldens studied succumbing to neoplastic disease.

A study published in the Journal of the American Animal Hospital Association found, in a five-way comparison of breeds, that golden retrievers and boxers died significantly more often from cancer than German shepherds, Labrador retrievers or Rottweilers.

Finally, a Dutch study from BMC Veterinary Research determined golden were not only at increased risk for tumor development -- but that certain tumors were more common in the breed than others.

In fact, London said goldens typically develop four types of cancer: hemangiosarcoma, an aggressive, often fatal malignancy of the lining of blood vessels, osteosarcoma or bone cancer, lymphoma and mast cell tumors. “The incidence of cancer begins to rise at six years of age and peaks at 10 to 12 then starts to fall off,” London said.

Cancer in dogs can be treated -- sometimes with good results.

“If you have certain cancers that can be removed, then it may be curative simply to have surgical removal of the tumor,” London said.

If it’s not a “removable” tumor, London urges pet owners to get multiple opinions.

“I think the world of cancer therapy in veterinary medicine is constantly evolving. And there are new options out there all the time,” she said.

Among those options: clinical trials at the Cummings School of Veterinary Medicine. Many of these require the ability to come to the Grafton campus for treatment, but they can offer promise -- especially for pet owners strapped for cash.

“So you get state of the art treatment with really no cost for your dog, which can be for many owners really welcome,” London said.

“Any time any of our patients get cancer it’s tough,” London said. “And anytime they lose the battle it’s tough. But every once in a while, we do see what we call our ‘exceptional responders.’ In fact, one of them is a golden retriever who lives in Maine, who is a long-time lymphoma survivor. He was involved in one of our clinical trials and is over a year out now.”

London says it’s hard to know how much progress they’re making against cancer in goldens and other dogs, despite the success stories. But she thinks in a year or two, they’ll have a clearer picture.

One area of concern for some dog owners has been the effect of spay and neuter operations on canine health. It’s just one study, but research published in PLoS One found neutering male Golden Retrievers did not make a significant difference in cancer deaths when compared with leaving the dog intact though it did find more spayed female goldens developing cancer than intact females.

Given the possible genetic component to cancer in goldens, is it possible to breed the “bad” genes out?

The short answer is yes. But don’t expect that to happen any time soon.

“Once we begin to really understand what’s in the genes of various breeds, there are techniques we can use to sort of edit those genes,” London said. “It’s probably a little ways off. But something there in the future.”

At present, golden retriever breeders can “suggestively” edit cancer out by looking for parental attributes, which might indicate a lower possibility of offspring developing the disease.

When breeding help dogs, Pauline Hoegler focuses on finding not only even-tempered parents but also dogs with a family history of long lives. However, she knows completely breeding-out cancer is impossible at this point.

"There's no getting around the fact that golden retrievers have cancer in their bloodlines," Hoegler said. "So I believe in having an open and honest conversation about what you do have."

What you do have in golden retrievers is an unusually persistent companion, said Allyson MacKenna.

“You’ll never go to the bathroom by yourself...if you have a golden retriever," she said. “They just want to be as close to you as humanly possible.”

That means they are not the dog for everybody. In fact, MacKenna says Yankee Golden Retriever Rescue has taken in goldens from owners who couldn’t handle the clinginess of their dogs. But she says for most golden owners that’s a big attraction.

“We have many more adopters, potential adopters, than we have dogs at any given time,” MacKenna said. “People who’ve had them come back over and over. They wouldn’t think of getting another breed of dog.”

But be forewarned if you’ve never owned a golden, not only do they prefer company but they need a substantial amount of exercise and consistent grooming. And beginning at age 6, London says, they need to be checked weekly for growths.

“And anything new needs to be investigated," she added. "So you should get a diagnosis if your dog has a lump.”

Goldens also have a tendency to steal your heart. And that can make the inevitable end — whatever way it comes — excruciatingly difficult.

MacKenna has lost several goldens over the years. Some to cancer. “Anybody who’s had one, I think, can attest to the fact that all the years of enjoyment and love that they give you back is well worth it,” she said. “And most of the people who’ve had one after going through the grieving period end up coming back for another one. And sometimes that’s the best legacy you can do for the dog you lost.”

RELATED: Puppy love: Westminster dog at the heart of a human romance

Comments on this article