This is a photo of Dr. Brenda Phillips, a veterinary oncologist, with her dog, Leo

The statistics are sad — and startling. One third of all dogs will be affected by cancer during their lifetimes. In fact, the disease ranks as the leading cause of death in dogs.

Dr. Brenda Phillips, a veterinary oncologist at Veterinary Specialty Hospital of San Diego, knows just how devastating cancer's impact can be — she's also a dog owner who's lost three Golden Retrievers to different forms of the disease.

This Saturday, Dr. Phillips will be a featured speaker at the second annual K9 Cancer Walk in San Marcos, Calif. The event is sponsored by the Morris Animal Foundation, a nonprofit group that has funded more than 35 oncology studies since launching its Canine Cancer Campaign in 2007.

Dr. Phillips shares ways that people can reduce the odds of their pets developing cancer — and why she's adopted a warrior’s stance when it comes to the pervasive disease.

Q. Why did you decide to specialize in veterinary oncology?

A. Dr. Brenda Phillips: Throughout my schooling, I was motivated by professionals who were passionate about oncology and research. I learned that you must focus on the whole being when you are in the field of oncology. Cancer has affected my family, my friends and, yes, my pets.

I come at cancer in a combative way. I have a warrior mentality. I will work as hard as I can with whoever is willing to work to fight cancer in people and in animals. We need to unify to find better ways to fight it. Every day that we have a defeat, we have someone who is celebrating, say, a third anniversary of a dog or cat being cancer-free. I strive to focus on the positive.

Q. What types of cancer did your own pets develop?

A. I love Golden Retrievers, and I’ve had three die of cancer. Mitch died last September from hemangiosarcoma [a cancer that attacks the lining of the blood vessels]. He was 7 ½ years old. Hansen was 13 when he died from high-grade sarcoma, and Parker was 12 when he died of histiocytic sarcoma in the brain.

Now I have Leo, a very entertaining Golden whom I adopted about 10 weeks ago. He is 4 ½ years old, and he comes to work with me every day at the hospital. He loves to greet people, other dogs and even cats. When I adopted him, I did a full general health screen, a set of X-rays and a head-to-tail evaluation. He had skin bumps that turned out to be benign. I am very motivated to do better and work even harder to improve our arsenal, so we can better diagnose, treat and prevent cancer in dogs and cats.

Q. What cancer-prevention tip can you share that may shock pet owners?

A. People are often surprised to learn that sunlight is a common cause of cancer in dogs and cats. Solar-induced cancers, such as squamous cell carcinoma, are often located on the underside, inner limbs, nose, lips, eyelids and ears.

Unfortunately, I see these pets after the cancer has developed. But I urge veterinarians in small animal practices to have conversations with families of pink-nosed cats who like to sunbathe and pink-bellied dogs, such as Italian Greyhounds. I recommend window treatments that do not restrict sunlight, but filter ultraviolet rays, as well as applying pet-safe sunblock and providing solar protective shirts for dogs out hiking. Fortunately, solar-induced cancer, if caught early, can be cured.   

Q. What happens to dogs who undergo chemotherapy?

A. Certain breeds are more sensitive to the side effects of chemotherapy, including Border Collies and Shetland Sheepdogs. These breeds are more likely to develop diarrhea or vomiting, and are lethargic at a more frequent and more severe level. Colorado State is working on a way to do dose reduction for these genetically prone dogs.

Breeds like the Poodle and Bichon Frise — ones with hair instead of fur — will experience thinning hair or may lose hair during chemotherapy. Breeds with double coats, like the Siberian Husky, are unlikely to have hair loss. Cats, surprisingly, don’t tend to lose hair, but they can lose whiskers or their whiskers become curly.

Q. How can people reduce the risk of cancer in pets — as well as improve the odds for recovery?

A. Have your veterinarian show you how to examine your pet's skin at home, so you know what to look for and what is normal. If something feels or looks different, that warrants a vet examination. It may not be cancer. Your pet could have another disease and, if treated promptly, have a better chance at a complete recovery.

Weigh your dog or cat regularly, because weight loss is a big sign. If your pet is receiving treatment for cancer, keep careful notes because documented observations are helpful. And if something doesn’t seem right to you, let your veterinarian know right away. Don’t wait just because your next scheduled visit is two weeks away.

To do your own part to help fight canine and feline cancer, look into walks and fund-raisers in your area through charitable foundations like the Morris Animal Foundation.