Standard Free Shipping | Free 2-Day Shipping (Orders $80+)

35% Off First-Time Subscriptions | Code: PET35

Mast Cell Tumors In Cats: Symptoms, Diagnosis & Treatment

Reading TimeReading Time:

Mast Cell Tumors In Cats: Symptoms, Diagnosis & Treatment

If you're a cat owner, you know that cats aren't just pets. They are often an essential part of your family, and keeping them healthy is a top priority.

Like humans, cats can develop conditions like tumors. One type of common skin tumor that cats can suffer from is mast cell tumors. Diseases due to mast cells commonly affect older cats. Learning all you can help you pick up on the symptoms and get your cat the veterinary attention that they need to get treatment.

While mast cell tumors can be cancerous or benign, it's still crucial to know as much as you can about mast cells. If your cat develops a tumor, you'll be able to make informed decisions. Keep reading the guide below to learn what you need to know about cats with mast cell tumors.

What's a Mast Cell Tumor?

First, it's vital to understand precisely what a mast cell tumor is. Put simply, a mast cell tumor consists of mast cells.

Mast cells are white blood cells found in body tissues. Among other things, mast cells release a compound called histamine, which many people will recognize as the compound responsible for allergic reactions.

Mast cell tumors form masses or nodules in organs, although the most common location is the skin.

There are three types of tumors due to abnormal mast cells:

  • Cutaneous
  • Intestinal
  • Visceral

Cutaneous: Skin

About 20% of these skin neoplasms are cutaneous, which means they are in the skin. These mast cells are common skin tumors and usually harmless, with about 90% diagnosed as benign.

As these forms of mast cells can be external, cat owners usually detect these early. They are also usually itchy and uncomfortable for your cat, so it's common for them to chew and itch the bumps formed by mast cells.

Visceral: Internal Organs

About half of these tumors from mast cells affect the spleen, meaning that they are visceral. It's also possible for the mast cells to affect the intestine, but the spleen is much more common.

Intestinal: Small Intestine

This form of mast cells is the most severe version of the tumor. When this is the case, the tumor has often spread to other organs and the lymph nodes, which results in fluid in the cat's abdomen.

What Are the Symptoms of Mast Cell Tumors in Cats?

CBD OIL FOR CATS | Innovet Pet Products

The symptoms of mast cells depend on whether the feline has mast cell tumors that are visceral or cutaneous.

As mentioned above, a standard indicator of cutaneous mast cell tumors is hard, hairless bumps on the skin. Because tumors affect histamines, this formation can result in side effects common in allergies like itching.

If the feline develops a visceral tumor, you won't see anything physically wrong with your cat. Instead, common symptoms include: 

If your cat has the most severe form of feline mast cell tumor, which would be in the intestines, then the symptoms of mast cells will be more severe.

These could include:

  • Diarrhea
  • High blood pressure
  • Stool with fresh blood
  • Vomiting
  • Black stool

How Are Mast Cell Tumors Diagnosed?

Feline Mast Cell Tumors | Innovet Pet

While learning about the symptoms might be scary, formally diagnosing this type of cancer of mast cells is easy to accomplish. A needle inserted in the mass suctions out some cells in a procedure called a fine-needle aspiration (FNA).

Once the vet has done this, they use a procedure called cytology. This process refers to examining the cells with a microscope.

Blood work is also a standard step that a veterinarian will take in diagnosis, but examining the cells under a microscope is the most accurate method.

A diagnosis can often result from this process, but sometimes the results aren't conclusive. There will need to be a biopsy of the tumor to remove mast cells for surgical examination in those cases.

While this process is much more invasive, it provides a lot of valuable information. A pathologist can determine the type of tumor, the margins between cancerous and healthy mast cells, the tumor diameter, and how aggressive it is through a biopsy.

How To Treat Mast Cell Tumors in Cats

First and foremost, the best option will be the surgical removal of the tumor. The feasibility of this option depends on the location of the tumor.

Tumors on the skin are much easier to remove than ones located on the spleen or the small intestine. In those cases, surgical removal can also be an option, but the entire tumor may not be removable if it is in the lymph nodes or small intestine. When this happens, a doctor will suggest radiation therapy for mast cells.

Grading System and Prognosis

Along with the different types of tumors, there are also grades assigned to each case of mast cells. These are more in-depth diagnoses and can help determine what kind of treatment is best for the feline involved.

There are two primary grading schemes used to determine these:

  • The Patnik System 
  • The Kipuel System

In terms of a diagnosis, the pathologist will often use both systems to get the most accurate result. The Patnik system grades these tumors as either a grade I, grade II, or Grade III.

The Kipuel system serves to clear up some of the ambiguity of the grade II explanation and instead assigns the tumor to one of two categories: low grade or high grade. 

The Patnaik System

Grade I

In terms of tumors, many practitioners consider grade I to have the best prognosis. Tumors of this grade tend to be on the skin and can be quite large, which may lead to panic. In actuality, these don't tend to spread beyond that first area.

These tumors are octopus-shaped, which means that it may look like one large bump on the surface but instead has "tentacles" that extend away from the growth of the visible mast cells.

Thus, even though these tumors can be easy to remove surgically with no need for chemotherapy or other treatments, it is critical to conduct a biopsy. A full report will ensure the removal of the tumor. If not, it has the potential to regrow. 

Grade II

A grade II tumor from mast cells is often "unpredictable," which makes prognosis difficult. When this is the case, a method called AgNor staining is often necessary.

With this procedure, the practitioner stains the tumor with silver particles, and a pathologist analyzes this to determine malignant behavior indicators. The uncertainty of this method first prompted the use of the Kiupel system. This system involved determining the mitotic index of the tumor. However, it can also be subjective.

Grade III

Grade III tumors make up an estimated 25% of these tumors of mast cells; they are the worst out of the diagnosis. At this stage, the tumor is aggressive and spreads to areas like the bone marrow, liver, and spleen. These organs are hard to treat due to the tumor's location.

Surgery for grade III on its own isn't usually effective, so treatments such as radiation therapy and chemotherapy are often the only course of action.


Feline Cutaneous Mast Cell Tumors | Innovet Pet

If you find yourself in a situation where you think your cat has a mast cell tumor, it's crucial to educate yourself about mast cells and seek advice from a veterinary professional. There are several types of feline mast cell tumors and different methods of treatment. A doctor can help you diagnose your cat with the right help it needs.

There are also products you can purchase to alleviate symptoms, like CBD gummies. With the help of a professional, you can choose which products are right for your pet.


Feline Cutaneous Mast Cell Tumors
Feline Mast Cell Tumor
Grading Cutaneous Mast Cell Tumors in Cats
Mast Cell Tumors in Dogs
Canine Mast Cell Tumors

    Recent Posts

    Using CBD Oil For Dogs with Cancer: What You Need To Know

    Using CBD Oil For Dogs with Cancer: What You Need To Know

    READ NOW Best CBD Oil For Cats With Cancer: What is CBD Oil and How Does it Help?

    Best CBD Oil For Cats With Cancer: What is CBD Oil and How Does it Help?

    READ NOW Bone Cancer in Dogs

    Bone Cancer in Dogs

    READ NOW Dog Oral Melanoma

    Dog Oral Melanoma

    READ NOW Mammary Cancer in Dogs

    Mammary Cancer in Dogs

    READ NOW Bone Cancer in Cats: Symptoms, Diagnosis, and Treatment

    Bone Cancer in Cats: Symptoms, Diagnosis, and Treatment

    Leave a comment

    Please note, comments must be approved before they are published