Cancer is the No. 1 killer of dogs and annually about 6 million dogs are diagnosed with the ailment, according to the animal cancer foundation.

On Sunday, more than 500 people and their dogs participated in the sixth annual VPI K9K Pet Cancer Awareness Walk around Shoreline Village and Rainbow Harbor.

They raised approximately $23,000, which will go to the nonprofit Animal Cancer Foundation, which funds research and increases public awareness of comparative oncology, the study of naturally occurring cancers in pets and people.

The foundation gives research grants to medical and veterinary oncology professionals studying comparative oncology models. The foundation doesn't fund studies that would induce cancer in pets.

Dogs can be diagnosed with several types of cancer, including, connective tissue, testicular, skin, mouth and throat, lymphoma and bone.

Participants paid from $30 to $40 to register in the walk.

VPI is Veterinary Pet Insurance, the oldest and largest pet health insurance company in the United States. It started in 1982.

- Phillip Zonkel

PET CANCER WARNING SIGNS

Here are a few warning signs for dog owners to watch.

A lump or a bump

A wound that doesn't heal

Any kind of swelling, including in bones

Enlarged lymph nodes

Drastic changes in a pet's appetite or weight

Unusually strong odors coming from a pet

Discharge or bleeding from any body opening

Difficulty chewing or swallowing

An unwillingness to exercise

If a pet has any of these symptoms, contact a veterinarian.

Source: Veterinary Pet Insurance