Cancer (Neoplasia) in Cats

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Cancer (Neoplasia) in Cats

In this article, you can learn more about the most common cancers seen in cats. We’ll discuss some of the causes or risk factors, symptoms, diagnosis, and treatment. We also provide help for living with the diagnosis, how to prevent cancer, and knowing when it’s time to say goodbye.

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Cancer, also called neoplasia, presents in many different, often nonspecific ways in cats. While cancer is usually diagnosed in senior cats, certain cancers can develop in cats of any age. There are many different forms of cancer, and since the symptoms are so varied, any lumps or bumps, wounds that don’t heal, changes in behavior including appetite, weight, litter box habits or activity often require further investigation by your vet.

Cancer: Benign vs. Malignant

Neoplasia can be malignant or benign. Benign cancer means that the tumor does not spread to other parts of the body. It can, however, grow and may need to be removed depending on the location. Malignant cancer spreads to lymph nodes as well as body organs such as the lungs, bones, brain, eyes, mouth, skin, liver, kidneys, and more. Small malignant tumors that are noticed early and have not yet spread to other organs, can often be surgically removed. This can give the cat an opportunity for a long and good quality of life. Chemotherapy can also benefit depending on the type of cancer.

Common Types of Cancer in Cats

There are many different types of cancers seen in cats. The following is a list of those we see most frequently. Please note, cats can develop other cancers not listed here.

  • Squamous Cell Carcinoma
  • Leukemia
  • Lymphoma
  • Mast Cell Tumor
  • Fibrosarcoma
  • Mammary tumors

Potential Causes of Cancer in Cats

Often the reasons cats develop cancer remain unknown. There are risk factors or other diseases that have been associated or known to cause cancer in cats including the following:

  • Feline Leukemia Virus
  • Unspayed females are at risk of mammary tumor(s)
  • Exposure to sunlight in lightly pigmented cats (especially the ears, nose, face)
  • Association with flea collars, canned cat food, canned tuna, and secondhand tobacco smoke
  • Certain breeds can be at higher risk of developing certain cancers
  • Associated with vaccines containing aluminum hydroxide adjuvants
  • Hormone injections

Signs and Symptoms of Cancer in Cats

Cats are skilled at hiding disease. Be alert to the following mild to more obvious signs or changes in your cat that require veterinary consultation:

  • Obvious lump or bump; you may notice it getting larger
  • Swelling
  • Nonhealing wound, may or may not have odor or discharge
  • Weight loss
  • Enlarged abdomen or belly, appearance of weight gain
  • Increased drinking or decreased drinking
  • Eating on one side of the mouth, drooling, dropping food
  • Foul odor from the mouth
  • Increased urination or decreased urination
  • Accidents outside the litter box
  • Hiding/sleeping in unusual places
  • Vomiting
  • Decreased activity, decreased behavior such as less affectionate or more aggressive
  • Dull, dry, flaky, and/or matted fur, not grooming as usual

How is Cancer Diagnosed in Cats?

Your vet will begin by asking you for a detailed history of your cat’s signs and symptoms including litter box habits, weight changes, eating and drinking habits, activity levels, and changes in behavior/moods. Your vet will also want to know vaccination history as well as if your cat has been tested for feline leukemia/feline immunodeficiency viruses, dates, and test results.

After a thorough physical exam, diagnostic tests including blood tests, x-rays or ultrasound, and urinalysis will be necessary to determine a diagnosis and the best way to treat and manage your cat. Your vet may recommend additional tests including a fine needle aspirate or a tissue biopsy.

Cancer Treatments Available for Cats

Treatment of neoplasia depends on the type of cancer your cat has been diagnosed with. The following list includes possible options that your vet will discuss with you depending on the type of cancer, location, whether it is benign or malignant, what to expect long term, quality of life, ongoing costs, and more.

  • Surgery
  • Chemotherapy
  • Nontraditional treatments
  • Palliative treatment
  • Pain management
  • Combination of the above

Living with a Cancer Diagnosis in Your Cat

Once your cat has been diagnosed with cancer, and depending on if it is benign or malignant, you and your vet will have to determine what is the best plan moving forward. Quality of life, which includes your cat’s response to treatment, recovery, what to expect, ongoing costs, pain management, and outcome, should be considered and discussed with your vet and with your family.

Preventing Cancer in Cats

While we cannot prevent all cancers, the following list is a guide to help minimize the development of cancer with known risks:

  • Vaccinate at-risk cats with the feline leukemia vaccine to prevent leukemia.
  • Spaying a female cat at an early age will decrease the risk of malignant mammary cancer.
  • Limit exposure to secondhand tobacco smoke as it has been shown to increase the risk of cancer in cats.
  • Keep lightly pigmented cats out of direct sunlight as much as possible.
  • Discuss the risks and benefits of feeding canned cat food and canned tuna with your vet.
  • Monitor your cat for any lumps and bumps or any changes to the ones he currently has. Have these checked by a vet right away.

Knowing When it’s Time to Say Goodbye

Knowing when to say goodbye to our beloved pets is one of the most difficult decisions we face. Cats don’t usually show signs of pain or illness in ways we expect them to. By nature, they’re very good at hiding their pain and discomfort.

Veterinarians understand and can explain often overlooked signs or symptoms to help you determine the right time. Knowing that we can relieve their pain and suffering, while heartbreaking, can also be comforting. Our pets give us their unconditional love and in return, we can relieve their suffering with a peaceful goodbye.

Talk to your vet about your cat’s quality of life to determine when to schedule to put your cat to sleep. Know what to expect during the procedure, including sedation so that your cat is sleeping peacefully and will not feel any anxiety or pain when the vet gives the final injection. Deciding to stay with your cat through the procedure is a very personal choice and there is no right or wrong answer.

Click on the following link to learn more about euthanasia:

Pet Euthanasia - Knowing When its Time and What to Expect

Read more:

Arthritis in Cats

Hyperthyroidism in Cats

Kidney Failure in Cats

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Published: 1/8/2021
Last updated: 9/2/2021
Dr. Denise Michanowicz, Veterinarian

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