Most Common Types of Cancer in Cats

Written and verified by the lawyer Francisco María García

Last update: 21 December, 2022

their cells grow abnormally and multiply without end. In such cases, start by learning what types of cancer are most common in cats. By knowing what cancer your pet has, you might be able to prevent cancer from becoming worse. 

Cancer is the number one cause of death in cats. One in five cats develop cancer, so it’s a good idea to paying close attention to your cat’s health as of a young.  A tumor forms due to cells multiplying at an uncontrolled rate. Tumors can either be malignant or benign, depending on how fast the cells grow and whether it can spread.

Leukemia is cancer that affects your cat’s bone marrow, which is where the body produces blood cells. A lot of abnormal cells get into your cat’s bloodstream and create too many lymphocytes, a kind of blood cell, which causes lymphoma.

Where cancer comes from

It could be due to genetics, sun exposure, or carcinogenic chemicals, which all can cause cancer in cats.  Things like feline leukemia virus and feline immunodeficiency virus can also lead to cancer. Luckily, they’re easy to detect.

It’s not always easy to prevent. Weakness, weight loss, poor appetite, bumps on and/or under the skin, bleeding, changes to their eyes, or wounds that don’t scab — if you see any of these symptoms, then take your cat straight to the vet. A strange meow, unhealthy fur, or restlessness might be signs of something wrong.

X-rays, ultrasounds, and biopsies (surgical or with a needle) can all help detect cancer in cats. Remember, you should also run blood tests every once in a while. 

CAT scans and MRIs are more sophisticated. However, they can confirm a diagnosis and help the vet plan the best treatment. It’s not easy to treat a cat with cancer, but its quality of life should always come first.

The most common types of cancer in cats

• Lymphoma is the most common type of cancer in cats. The tumor starts out as a white cell called a lymphocyte, which is part of the immune system. It can develop in several places: lymph nodes, chest cavity, digestive tract, nasal cavity, kidneys, and nervous system.
• Squamous cell carcinoma affects the skin and could develop from being exposed to the sun. The tumor is usually in the nose or ears, and you might notice certain wounds not healing properly. Fortunately, this kind of cancer kind doesn’t usually spread.
• Mammary carcinoma affects the mammary glands and usually happens to females. However, males aren’t completely safe either, even if they’re sterilized. Symptoms include swelling and inflammation, and it can spread to the lymph nodes and lungs.
• Surgery, chemotherapy, and radiation therapy are all potential treatments. Many cats make a full recovery.
• If you start treating your cat’s cancer when the tumor is small and in one place, it can make a big difference, because the sooner you get rid of the tumor the better.

Types of cancer to treat with great care

• Mastocytoma can affect the skin, spleen, and intestines. It’s especially aggressive in those organs because it blocks their digestive system. It’s likely to spread to the lymph nodes, lungs, liver, or spleen. That’s why surgery, radiation therapy, and chemotherapy are usually the best options.
• Oral squamous cell carcinoma starts in the cells covering your cat’s mouth and throat. It can affect their tongue, and even their bones and lymph nodes. It causes problems with eating, salivation, and halitosis, and it’s hard to treat.