Caring Hands, Compassionate Hearts.


4 Common Cancers in Dogs

Cancer is common in dogs, as much as we hate to say it. Our pets are members of our families, so if our dogs get the most dreaded diagnosis, it’s scary. It’s upsetting. Dogs and humans have a lot in common with regard to cancer. They can get many of the same kinds that we can and often have very similar treatment options.

For all pet owners of any species, it’s good to have a basic familiarity with potential health problems that they might encounter in the future. This includes everything from hip dysplasia and diabetes to cancers. It could inform your decision on choosing a breed, preventive care choices, signs to look for and when to seek a diagnosis, as well as on treatment options.

The types of cancers that are common in dogs can affect bone, blood, soft tissue, etc., so the signs and symptoms can vary greatly. Let’s take a look at a few of the most common cancers to be aware of.

Cancer is common in older dogs.Lymphoma

Lymphoma accounts for 7-14% of all cancers in dogs, making it one of the most prevalent cancers. Dogs are more likely to develop this type of cancer than humans are. There are many types of lymphoma. Some progress slowly and are well-managed while others are very aggressive. The most frequently seen sign of lymphoma is enlarged, firm lymph nodes, though this may vary. Chemotherapy is the most effective treatment, but radiation and tumor removal are also options for some dogs.

Mast Cell Tumors

Mast cell tumors (MCT) make up about 20% of skin tumors in dogs. They can take on many shapes and sizes, even resembling common benign tumors like lipomas. They can also change quickly, becoming larger or even smaller. Any skin mass that is removed should be biopsied to confirm that it isn’t MCT given the varied nature of their appearance. Surgical removal is the primary treatment, but supportive radiation can also be beneficial.


Melanoma is a cancer of pigment-producing cells. In dogs, these are most often found in the mouth, but may also appear elsewhere, including toes and nail beds. They typically appear as enlarged tumors that are found after a pet owner notices excessive drooling, bad breath, or that the pet is dropping food. Melanomas should be removed surgically, but radiation before surgery can help to shrink the tumor before removal.


Osteosarcoma accounts for about 85% of bone cancers in dogs. It is seen most often in large breeds and usually appears in the legs. The most common sign is simply lameness, as bone cancers are very painful. Amputation is the best treatment, and while this may sound extreme, dogs as a whole adjust remarkably well to running and playing on three legs. Unfortunately, amputation does not guarantee that the cancer will not still metastasize elsewhere over time. As with all illnesses, treatments should be evaluated on a case-by-case basis.

Perhaps the most important thing to take from all this information is that life-threatening illnesses can often have subtle symptoms and limited windows of time for intervention. Careful attention at home and prompt diagnosis by a veterinarian are so important to the life of your furry family member.

If you have questions or concerns, always feel free to call!