Mast Cell Tumors in Cats

Siamese cats have been one of the most popular cat breeds for decades. They have a lot of positives, but also are prone to certain medical conditions, like developing mast cell tumors, also called MCTs or mastocytomas. Mast cell tumors can appear in any breed of cat, but are seen most often in older Siamese cats. Ambassador Animal Hospital of Columbia, SC, looks at the facts about these kinds of feline tumors.

What Is a Mast Cell?

Mast cell tumors get their name because they contain mast cells, which are a kind of white blood cell. They usually help the body deal with allergens and help protect against some kinds of infections.

Are There Different Types of MCTs?

There are two types of MCTs. The first type is cutaneous MCTs, which grow under the skin. It’s the second most common kind of tumor in cats. The second type of MCT is called visceral, which grows in the internal organs, usually the spleen or intestines.

Are MCTs Always Cancerous?

Not all MCTs are cancerous. About 90 percent of all cutaneous MCTs are benign. Unfortunately, visceral MCTs are cancerous. Just how mast cells grow tumors is unknown, but are most likely reliant on a variety of factors, including genetics.

Are MCTs Fatal?

The bad news is that cancerous MCTs are often fatal if not caught in time. The cancer spreads to other organs or the lymph nodes. A cat with visceral MCTs lives an average of a year. The good news is that MCTs can be treated by your veterinarian if caught in their early stages.

When Should I Bring My Cat to the Vet?

MCTs appear like flat, hard lumps or small bumps. If your cat has visceral MCTs, then he will often have blood in his stool, and experience chronic diarrhea and vomiting. A veterinarian needs to see your cat if he experiences these symptoms.

Still Have Questions?

If you still have questions about mast cell tumors in cats that have not been answered here and live in the Columbia, SC, area, contact us at Ambassador Animal Hospital at (803) 787-3840 or fax (803) 667-9797 to make an appointment today.


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