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Today we come to you with the information every cat caregiver needs to know about types of cancer in cats, and cancer prevention, detection and treatment. If you would like to understand what lies in the roots of this complex issue too, please read the first part of this article posted previously.

Today we come to you with the information every cat caregiver needs to know about types of cancer in cats, and cancer prevention, detection and treatment. If you would like to understand what lies in the roots of this complex issue too, please read the first part of this article posted previously.

This blog will focus on the following questions:

1. What types of cancer are most seen in cats?

2. How to detect feline cancer?

3. What are the possible treatments of feline cancers?

4. What can I do to protect my cat from cancer?

These are the concerns of all of us cat lovers, so let us break this down for you and help you stay informed.

1. What types of cancer are typically seen in cats?

a) The most common form of cancer in cats is lymphoma, which is often associated with the above mentioned feline leukemia virus (FeLV). It is estimated that feline lymphoma accounts for about 90% of all blood cancers in cats and for about 25% to 33% of all cases of cancer in cats.

Lymphoma is cancer of the lymphocytes, a type of white blood cells that have a very important role in the immune system. Some of the most common forms of this cancer are the following:

1. Mediastinal form – occurs between pleural sacs/lungs;

2. Alimentary form – occurs in the gastrointestinal tract, abdomen and liver;

3. Multicentric form – occurs in the lymph nodes;

4. Solitary form – this one can occur in any location;

5. Renal form – occurs in the kidneys.

Symptoms can highly vary depending on the form of the lymphoma, but the most common symptoms are: lumps that vary in shape or size, sores that do not heal, changes in bowel or bladder habits, urinating difficulties, eating difficulties, strange bleeding, changes in cat’s appetite and body weight, coughing and breathing difficulties and oral odor.

b) Less common among cats are feline skin tumors. White cats are generally more prone to this type of cancer. Skin tumors usually form visible lumps on the skin and can affect vision, smell or eating. Benign skin tumors are more difficult to detect due to their mobility and long period of development. Note that not all bumps and lumps are in fact cancer! There are a lot of other causes to bumps that do not necessarily represent an abnormal tissue growth. If you notice anything odd on your feline’s skin, it is recommended to pay a visit to a vet and have it checked immediately.

Third most common feline cancer is the cancer of mammary glands that usually manifests as a lump in the breast tissue. This cancer accounts for the most frequently seen cancer in female cats older than 10 years.

Mammary cancer in cats

It is not known what exactly causes this form of feline cancer, as the underlying genetic factor hasn’t been found yet. However, the hormone status and breed seem to play a role in the development of this cancer. Dr. McEntee says: “If these hormones [estrogen and progesterone] are given to unspayed cats as contraceptives or for behavior modification either orally or by injection, their risk of mammary cancer can triple.” She also notes: “Siamese cats, for unknown reasons, have twice the risk of other breeds, and they also tend to get the cancer at an earlier age.”

It is estimated that spaying the cat before the age of six month reduces the risk of mammary cancer by 91%. Spaying cats also decreases the chances of ovarian cancer by 40-60% (read more in section 4. What can I do to protect my cat from cancer?)

c) One of the rarest and most difficult to treat of all feline cancers are the abdominal cancers. These cancers are often followed with poor digestion and weight loss, overall weakness, vomiting and abdominal enlargement.

2. How to detect feline cancer?

Detecting abnormalities at early stage is very crucial when it comes to the treatment of this complex disease. Common diagnosing methods are physical examination, x-rays, ultrasounds, blood and urine tests and cytology tests.

Some cancers are easier to detect than others. For example, skin and mammary tumors often manifest with physical symptoms that the cat owners often notice themselves. In such occasions, it is mandatory to pay a visit to the vet without a delay!

Unfortunately, not all cancers can be diagnosed by a visual observation and other diagnosing methods must be conducted.

X-ray of FeLV-positive cat with lung cancer

3. What are the possible treatments of feline cancer?

The strategy of treating cancer in cats is determined when the diagnosis has been established and type and size of the tumor has been described. If it is possible to determine the exact location of the tumor and if the location is accessible, then the cancer can possibly be surgically removed. This is by far the most common choice of treatments for feline cancer. Often, radiation, chemotherapy and immunotherapy can also be utilized depending on the diagnosis.

Today, there are a lot of research studies out there looking for more precise and personalized ways to cure cancer in humans and our companion animals. For example, in human medicine, liposomes and nanoparticles have lately been examined as drug delivery systems for anticancer agents. Liposomes and nanoparticles have the ability to target cancerous cells and therefore can allow a more precise application of the drug, which would greatly decrease the negative side effects of free cytostatic drugs.

To quote Ziebelska-Koczywas and Lechowski: “The application of nanotechnology in medicine may solve these problems as nano-carriers can be targeted to specific tissues, reach certain subcellular compartments, or target malignant cells in circulation via active targeting. Nano-therapies can also accumulate or be retained in tumors using.”

In veterinary medicine, liposomes have so far been the most investigated drug delivery systems. If you are interested in this particular approach in cancer treatment, we highly recommend reading the research report “The Use of Liposomes and Nanoparticles as Drug Delivery Systems to Improve Cancer Treatment in Dogs and Cats.” by Ziebelska-Koczywas and Lechowski. You can find free access to the full article here.

4. What can I do to protect my cat from cancer?


Just like in humans, major factors that can affect the risk of developing cancer in cats are lifestyle and genetics. Make sure to provide your cat with the healthiest lifestyle possible. Feed your kitties fresh and diverse diet. Like Lisa P. Weeth said: “There are no proven dietary strategies or techniques to prevent cancer development in dogs and cats. […] Genetic factors and environmental toxins may not be avoidable or preventable, but avoiding obesity and feeding a complete and balanced (no deficiencies, no excesses) [diet] are within every caregiver’s control.”

Always provide your cats with enough activity and minimize indoor pollution. Avoid exposing your cat to cigarette smoke and direct sunlight for prolonged periods. If your kitty is white, it is not recommended to let her out on sunny days between 10 am and 4 pm, when the sun is at its highest peak. If this is not an option for you, they you may want to consider sun block, which is available for cats.

Spaying and neutering has also been linked to the level of risk of cancer development. Spaying female cats can decrease the risk of mammary gland cancer, ovarian cancer and uterine cancer development, as it prevents them from going into heat. This is because the primary cause of these cancers are reproductive hormones, and spaying prevents cats from going in heat. Same way, neutering males can help reduce the risk of developing testicular cancer, as it would make them less subjected to FeLV and FIV.

Furthermore, a major factor in treating cancer is, of course, early diagnosis. The best possible advice is to take your feline friend to regular veterinarian check ups which will drastically increase the chances of finding odd signs and symptoms at an early stage. If you ever notice anything that worries you, check with your feline’s vet immediately.

As you can see, there are many different types of cancer in cats and very diverse approaches when it comes to its detection, treatment and prevention. Know what to look for and what to do to ensure the best life for you and your pet. Knowledge is PAwer!