Skin cancer isn't a topic anyone wants to discuss, but unfortunately this disease can affect not only people but also cats. It's helpful for pet owners to know the causes of skin cancer in cats and whether or not it can be prevented or treated. Skin cancer is an awful disease but there are things cat owners can do.
What Is Skin Cancer?
Skin cancer occurs when abnormal cells in tissue grow or divide uncontrollably. There are many types of skin cancer in cats and the early stages of it cannot be seen with the naked eye. But as it develops, there are various signs of the disease. Depending on the type and severity of the skin cancer, it can result in serious problems if it spreads throughout the body. Skin cancer often appears as a tumor, but not all tumors are cancerous.
According to the Cornell University College of Veterinary Medicine, the four most common types of skin cancer in cats are:
- Basal Cell Carcinomas
- Mast Cell Tumors
- Soft Tissue Sarcomas (including fibromatosis, fibrosarcomas, and injection-site sarcomas)
- Squamous Cell Carcinomas
Other types of skin cancer in cats include:
- Lymphoid Tumors (including lymphomas and epitheliotropic or nonepitheliotropic skin lymphosarcomas)
- Nerve Sheath Tumors
- Sebaceous Gland Adenocarcinomas
- Fibrous Histiocytomas
- Apocrine Gland Adenocarcinomas
Signs of Skin Cancer in Cats
Signs of Skin Cancer in Cats
- Lump or bump on or under the skin (tumor)
- Discoloration of the skin or fur
- Skin inflammation or rash
- Sores or ulcers that won't heal
It can be difficult to notice the signs of skin cancer in a cat but if you feel a lump or bump on your cat, it may be a tumor and therefore a type of skin cancer. Not all tumors are cancerous, though, and without running diagnostic tests with your veterinarian, you won't be able to tell what kind of tumor it is. Other signs of skin cancer can include finding an area of hair loss or discoloration of the skin or fur. Sometimes skin cancer can also cause localized bruising, itching, a rash or inflamed area of skin, and sores or ulcers that won't heal.
Causes of Skin Cancer
There is not always a known cause for a cat's skin cancer but several factors may play a role in the development of this disease:
- Chemical carcinogens
- Photodamage/long-term solar radiation
- Hormonal factors
- Genetic factors
- Skin trauma
Diagnosing Skin Cancer in Cats
If you suspect your cat has skin cancer, a full physical examination should be performed by your veterinarian. Any physical signs of skin cancer will be examined and various diagnostic tests may need to be performed including biopsies, cytologies, blood tests, and fine needle aspirates. These tests will look for indications of abnormal cells and changes in organ function to determine whether a cat has skin cancer or not, but sometimes surgery is needed to remove the lesion or tumor in order to make a diagnosis. Additional tests including X-rays and ultrasounds may be indicated to look for signs of metastasis depending on the type of skin cancer and your cat's symptoms.
The treatment for skin cancer will vary depending on the type and severity of it. Surgery is commonly recommended as well as chemotherapy, radiation therapy, antibiotics, pain medications, and other therapies. Mohs paste may be recommended to manage non-healing skin wounds that are due to skin cancer and sometimes even cryotherapy and injectable treatments are utilized. Some skin cancers are incurable so the symptoms are managed with a goal of slowing the disease progression and maintaining your cat's quality of life.
How to Prevent Skin Cancer
It is difficult to completely prevent skin cancer in cats, but there are a few things you can do to lower the likelihood of it occurring. Injections should be kept to a minimum, only giving necessary vaccines recommended for your cat. In order to limit the chance of your cat developing an injection-site sarcoma, adjuvanted vaccines should be avoided. Cats with a history of skin cancer should not be bred in case there is a genetic component to the disease, and white or hairless cats should be kept out of the sunlight and other UV lighting.
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