Cancer in Cats

Cancer in cats is not as common as it is in dogs. Unlike dogs, cats can hide that they are unwell. Therefore making it much harder to detect.

Cancer is a class of diseases in which abnormal cells grow uncontrollably, invading the surrounding tissue, and can spread to other areas of the body. Cancer can grow localised in growths or lumps (tumours) or generalised (spread throughout the body).

There are two different tumours: Growths and lumps are “benign tumours” and tend to not spread to other parts of the body and surrounding tissues.

In contrast to this, ‘malignant’ tumours often invade surrounding normal healthy tissue and may spread to other sites in the body (or ‘metastasise’), typically spreading via the bloodstream or lymphatic system.

Types of Cancers

Cats are susceptible to a variety of cancers, and the top 5 types are:

Lymphoma is a cancer of a type of blood cell (lymphocytes) and lymphoid tissues. Lymphoid tissue is normally present in many places in the body, including the gastrointestinal tract, the chest structure, the liver, spleen, and kidneys. The age of affected cats ranges, on average, from 2 to 6 years, although a cat is susceptible to lymphoma at any age. Infection with the feline leukemia virus increases the risk of developing lymphosarcoma.

Feline Leukemia Virus (FeLV)-FeLV was one of the leading causes of lymphoma in cats until the development of the FeLV vaccine.

Mammary (breast) Cancer-Mammary tumors develop in older cats. Desexing cats before their first heat, lessen the risk of future mammary tumor development. Mammery cancer is quite rare in male cats.

Skin Cancer (squamous cell carcinoma)-Squamous cell carcinoma accounts for a high percentage of all feline skin tumors. These tumors usually involve light or unpigmented skin, and sun exposure increases the risk of a cat developing SCC. The most common locations are the hairless area of the nose, eyelids, and ears.

Fibrosarcoma-Fibrosarcoma is an aggressive tumor that develops from fibrous connective tissue.

 Symptoms to look out for:

• Abnormal swellings that persist or continue to grow
• Sores that do not heal
• Weight loss
• Loss of appetite
• Bleeding or discharge from anybody opening
• Offensive odor
• Difficulty eating or swallowing
• Hesitation to exercise or loss of stamina
• Persistent lameness or stiffness
• Difficulty breathing, urinating, or defecating

In addition, other signs, such as pain, fever, anemia, drinking too much water, producing excessive urine, and ravenous appetite.

Diagnosis

• Physical examination involves using physical examination with visual observation and manual palpation.
• X-rays: identify tumours of the lung, gastrointestinal tract and bladder.
• Ultrasonography visualises internal bodily structures and can diagnose internal tumours. Internal cysts (which may become tumours) are viewable and the size and structure of the organs.
• Cytology involves removing cells from the affected area, such as mammary gland secretions, nasal secretions, respiratory secretions, bone marrow and lymph nodes. This rules out bumps that may be abscesses, cysts, or granulomas.
• Nuclear scanning views the liver, thyroid, lung, spleen, kidney, and bones.
• Blood tests confirm or discount suspected cases of feline leukemia or feline immunodeficiency virus. An immunoflourescent antibody (IFA) test is available for the detection of FeLV in the blood of infected cats.

Treatment

Cancer accounts for approximately 32% of deaths in cats over ten years old. Having your cat diagnosed early, treatment can be successful.

• Surgery-Utilised if the tumour is localised and accessible. Removal of all malignant cells to prevent the cancer spreading. It continues to be the most common choice for treatment of cancer in felines.
• Radiation is used to control or cure cancers provided: the tumor targeted falls in the range suitable for radiation, no radiosensitive organs are involved, and it can be meta-sized. Performed either internally through implants (brachytherapy), or externally by using radioactive beams (tele-therapy). This destroys the DNA of the cells and ensures reproduction chances are diminished.
• Chemotherapy breaks down the chromosomes of the cell or tumor, so that cell division becomes impossible. This stops the affected cells from reproducing or spreading to other parts of the body. Chemotherpay does have side effects. These include bone marrow depression, nausea, hair loss and hemorrhaging. However, it does not work effectively against large tumors.
• Immunotherapy works on the premise that many cancers occur because the organism’s immune system is locally suppressed by the cancer cells. It asserts that the tumor would have been eliminated if the tumor microenvironment had not been suppressive. Rather than employing external procedures, it stimulates the animal’s own system to fight the cancer. A good example of this methodology is the use of monoclonal antibodies in triggering the body’s immune system to fight any cells to which it attaches.

Prevention

Spaying your cat will drastically reduce their chance of getting mammary cancer. Preventing the development of feline leukemia, either through vaccinations or making sure when you get a cat that the cat hasn’t been exposed to feline leukemia, will decrease the likelihood of developing lymphoma.

But it’s so hard to say how to prevent something when you don’t know what causes it most of the time. So early evaluation and detection is probably the better approach in terms of improving outcomes.

1.  “Feline Cancer Resources”. Retrieved 2012-03-22.
2. Eckstein, Sandy. “Cancer in Cats: Types, Symptoms, Prevention, and Treatment”. WebMD. Retrieved 2012-03-22.Eldredge, Debra (2005). Cancer and Your Pet. Capital Books. ISBN 9781931868860. Retrieved 2017-04-01 – via Google Books.
3. Wells, Virginia. “Feline Cancer: What are the Warning Signs?”. Intelligent Content Corp. Retrieved 2012-03-22.
4. “Lymphoma in Cats” (PDF). Southern California Veterinary Specialty Hospital. Archived from the original (PDF) on 2012-10-30. Retrieved 2012-03-22.
5. “Skin Tumors in Cats: An Overview”. Petwave. Archived from the original on 2012-06-10. Retrieved 2012-03-22.
6. “Cancer in Cats” – Wikipedia