The American Veterinary Medical Association estimates that as many as one in three dogs will get cancer, and that 50 percent of dogs above the age of 10 years will die from it.

Cancer is the leading cause of disease-related death in dogs, and I have lost five dogs to this devastating killer.

The first was a mixed-breed, my childhood friend, and over the last 30 years, four beloved golden retrievers.

In fact, statistics show that goldens are the most common breed to develop cancer, with 60 percent dying from it, which is more than twice the average rate for all breeds. That's a bitter pill to swallow when it comes to owning one of the most wonderful breeds of dog in the world and one that finally became a deal-breaker for me.

And goldens are not alone in their genetic predisposition for cancer; statistics show that other breeds are more susceptible than others:

Highest risk: Boxers, Golden retriever, Rottweiler, Bernese Mountain Dog

High risk: Boston terrier, English bulldog, Scottish terrier, Cocker spaniel

Average risk: Irish setter, Schnauzers (standard and miniature), Labrador retriever, mixed-breed

Lower risk: Beagle, Poodle (standard and miniature), Collie, Dachshund

But thanks to many dedicated breed clubs, much is being done in the fight against canine cancer. One study co-sponsored by the Golden Retriever Foundation has researchers collecting blood and tissue samples from goldens with lymphoma and hemangiosarcoma and comparing them with blood samples of older goldens who have remained cancer-free to see if there are gene variations that could predispose certain dogs to cancer, as well as for markers that will allow for early detection.

And although most cancers are still non-curable, the AVMA says that with advanced techniques veterinarians are now able to treat canine cancer, which allows many dogs to live a quality life despite a cancer diagnosis.

The key is early detection, and they offer these 10 common signs of cancer for owners to watch for:

* Abnormal swellings that persist or continue to grow

* Offensive odor

* Sores that do not heal

* Difficulty eating or swallowing

* Weight loss

* Hesitation to exercise or loss of stamina

* Loss of appetite

* Persistent lameness or stiffness

* Bleeding or discharge from any body opening

* Difficulty breathing, urinating or defecating

Owners should examen their dogs from head to toe on a regular basis and note such issues as suspicious lumps, bumps or swellings (don't forget inside your dog's mouth). Keep a record of anything unusual, including changes in attitude or behavior, and report it to your veterinarian.

Reduce your dog's exposure to environmental factors such as pesticides and herbicides that have been linked to an increased risk for canine cancer and keep your dog in lean and fit condition.

And remember that support for foundations that seek to understand how cancer impacts our companion animals helps in providing better treatment options for humans.

-- Sherry Davis is a dog trainer/owner of CSI 4 K9s. Email her at These are her opinions, not necessarily The Californian's.