By Dr. Ann Hohenhaus for Vetstreet
May is Skin Cancer Awareness Month, but it isn't just humans who need to be concerned about the pitfalls of too much sun exposure.
As a veterinary oncologist, I meet many vigilant pet owners who want to know how they can keep their pets healthy and identify cancer early on. The good news is that veterinarians can usually treat skin cancer successfully -- as long as it's promptly identified.
Based on my professional experience, I've compiled five facts about skin cancer and pets that are sure to surprise you.
Pets Get Skin Cancer, Too
I'm always amazed at how many pet owners are shocked to learn that their pet has skin cancer. Both dogs and cats can develop skin cancer, and the common forms of skin cancers found in humans -- melanoma, squamous cell carcinoma and basal cell carcinomas -- are also seen in pets. Fortunately, basal cell carcinomas are relatively uncommon in animals, but melanoma and squamous cell carcinoma are all too common.
Skin Cancer That's Common in Pets -- But Not People
Normally, mast cells play a role in allergic responses -- they are responsible for the itching, swelling and redness in your skin when you contact an allergen. Although dogs and cats who suffer from allergies are not more prone to developing mast cell skin tumors, certain breeds of dogs -- including Labrador Retrievers, Boxers, Pugs and Golden Retrievers -- are predisposed to developing this type of tumor.
Owners of these dogs need to be especially vigilant about unusual skin masses, but any pet owner should be concerned about raised, hairless, pinkish-yellow masses, which could be mast cell tumors.
Mast cell tumors in cats look very similar to those in dogs. Because mast cells induce itching, swelling and redness, mast cell tumors may be red, itchy and periodically swell up and then disappear.
Melanoma Of The Mouth
Our own doctors see every freckle as a potential melanoma. Melanoma also occurs frequently in dogs, but much less so in cats. Melanomas of the haired skin in dogs are usually benign -- the bad ones occur in the mouth, on the gums and where the nails meet the toes. And although orange cats frequently develop freckles on their lips and gums, these flat accumulations of pigment are normal and known as lentigo simplex.
Sunbathing Is Also Bad For Your Pet
For the most part, our pets have dense fur that acts as a natural sunscreen, but white-coated dogs and cats are the exceptions to this rule. In sunny parts of the country where pets spend a lot of time outside, like California and Colorado, sun exposure takes its toll on the thinly furred skin of the ears and nose of white dogs and cats. Dogs who sunbathe on their backs are also prone to developing squamous cell carcinoma in the thinly haired region of the tummy. Solar-induced squamous cell carcinoma can be treated with surgery or radiation therapy if found early, but prevention is simple: Limit your pet's exposure to the sun.
Needles That Do More Than Prick
A rare but important tumor that afflicts cats sometimes forms at the site of a subcutaneous injection. The injection induces inflammation that, for some unknown reason, transforms into a malignancy. Millions of cats get injections, and yet only a few develop these tumors, which are commonly known as injection site sarcomas. Why some cats do and others don't is a frustrating conundrum for cat owners and veterinarians.
About 15 years ago, a group of experts in the field developed a guideline called 3-2-1 for the management of lumps at injections sites. The guideline advises that if a lump is present three months after an injection, and it's larger than two centimeters or is growing just a month after an injection, it should be biopsied to determine if it is a benign or a malignant mass.
This quick look at skin cancer in dogs and cats is just scratching the surface of this important disease. If you find a lump or sore anywhere on your pet's skin, see your veterinarian as soon as possible.
For more on pet health, click here.
Flickr photo by nimetimesthree