What causes cutaneous SCC?
Cutaneous SCC is a form of skin cancer usually associated with exposure to Ultra Violet radiation from the sun, in a similar way to Malignant Melanoma in humans. Dogs and cats with pale skin are particularly at risk, especially if they spend a lot of time out in the sun. The disease tends to appear on areas of skin not protected with fur, such as the nose and ear tips, eyelids, and belly/groin in dogs.
How can the disease affect my pet?
Cats are most commonly affected on the face, especially the ear tips and nose. The tumours are usually small, and look like a scratch that does not heal. They can also start as an area of flaking, thickened skin, especially on the ears. If left, these signs can progress to very sore and nasty looking ulcers. In dogs, the belly is the most frequently seen site for the problem, and usually starts with thickened, flaking skin. This can then progress to a more lumpy, nodular appearance. In the early stages these changes are pre-cancerous, and removal of the affected skin is curative, although the rest of the skin remains prone to recurrence. As the disease progresses, the tumours can become more aggressive, causing local ulceration and invasion of underlying tissue.
This cancer is relatively slow to spread, and in most cases if the affected skin can be removed then the disease can be cured. However, it is important to check for any signs of spread before treatment is initiated. The vet will check the local lymph nodes: this may involve looking into the abdomen with ultrasound if the disease is on the belly or groin. Sometimes a chest Xray may be advised.
How is the cancer treated?
As stated above, surgical removal is the most effective treatment for cutaneous SCC. This involves careful assessment of the edges (or "margins") of the tumour, both across the skin and deep into the underlying tissues, then cutting away any affected tissue under anaesthetic. The removed tissue will then usually be sent to the laboratory to check that the margins are clear of tumour. This can mean quite dramatic looking surgery, such as removal of ear flaps or nose tip in the cat, or fairly extensive skin surgery in the dog, but if this results in removal of all the cancerous tissue, the pet will be cured. If the cancer is of a size where complete removal is not possible or feasible, then sometimes less aggressive surgery or other treatment methods such as chemotherapy may be suggested to help to reduce the tumour and improve the quality of life for your pet.
How can I reduce the chance of my pet being affected, or avoid recurrence of the problem?
Reducing exposure to sunlight is the main way of avoiding this type of cancer. This may mean keeping a cat indoors during the middle of the day; introducing more shady areas into a yard where a pet spends time, and encouraging or training the pet to stay in the shade; or using purpose designed sunsuits for dogs who refuse to give up their dangerous sunbaking habits.
Remember: if you have any questions regarding your own pet’s treatment, please do not hesitate to ask your vet.