You might not give much thought to dogskin cancer, because your loyal
companion is covered with hair and protected from the sun. But you should know
that skin tumors, which may be cancerous, are the most common tumors found in
dogs. Fortunately, when caught early, many cases of dog skin cancer can be
Not all varieties of dog skin cancer are caused by sun exposure, but sun
damage to the skin can be a causative factor. All dogs have certain areas, such
as the nose and the pads of the feet, where there is no hair to shield
sensitive skin from the sun. Additionally, pooches with light-colored or thin
coats are more susceptible to sun damage over their entire bodies.
Because some types of dog skin cancer, including dog melanomas and mast cell
tumors, are fatal if untreated, it is important that you have your veterinarian
check any suspicious growths.
There are different types of dog skin cancers. Three of the most
Malignant melanoma. Just as in people, malignant melanoma is a type
of skin cancer in dogs that affects pigmented cells known as melanocytes. Dogs
often develop benign tumors in pigmented cells that do not metastasize, which
are called melanocytomas. These tumors are found on areas of the dog’s body
that have hair.
Most malignant melanomas occur on the mouth or mucous membranes, although
about 10% of the time they are found on parts of the body covered with hair.
They tend to grow extremely fast and are likely to spread to other organs,
including the lungs and liver.
No one knows exactly why melanomas develop, although genetic factors seem to
play a role. Additionally, trauma or compulsive licking of a particular spot on
the skin may increase the likelihood that cells will multiply, thereby raising
the chances that cells will mutate during the division process and become
Squamous cell carcinoma. This form of dog skin cancer, which occurs
in the epidermis, is often caused by exposure to the sun. Scientists believe
there may also be a connection between the papilloma virus and the development
of squamous cell tumors in certain dogs.
Although squamous cell cancers do not spread to surrounding lymph nodes,
they are aggressive and may lead to destruction of much of the tissue around
Mast cell tumors. These dog skin cancers, which occur in the mast
cells of the immune system, are the most common skin tumors in canines.
Veterinarians don’t know what causes mast cell tumors to develop, although
there have been cases where they have been linked to inflammation or irritants
on the skin. Evidence suggests genetic factors are often important, and the
hormones estrogen and progesterone may also affect cancer growth.