Cat Health and Cancer
photo by McBeth under a creative commons license (see below for caption)
As cats live longer there are more reports of cancer in cats. Cat Health and Cancer is becoming more of an issue for cat keepers. Although cancer is not confined to older cats.
The causes of some cancers are known but as we all know billions of dollars and pounds continues to be spent on research into the causes of cancer, so we simply do not know, in many cases, the causes of cancer.
The incidence of cancer in cats in the US is about one half that of dogs (src: http://maxshouse.com) and stands at between about 150 to 450 per 100,000 cats. There is a high incidence of soft tissue tumors (35-45%) . 70% of tumors are malignant. Cats over 5 years of age are most likely to get cancer.
Cat Health and Cancer - Types of Cancer
Cancer refers to malignant tumors. "Malignant" means bad and bad in this case means a harmful tumor that can invade and damage nearby tissue and worse (by traveling through the blood stream). A "tumor" is a growth of tissue that serves no function and which grows in an uncontrolled and progressive manner by multiplication of the cells in the tumor. Benign tumors are ones that do not spread to other parts of the body.
Here are some types of malignant tumor or cancer:
---Squamous cell carcinoma - skin cancer. The word "squamous" comes from squamous cells, which are thin flat cells found in the tissue that makes up the skins surface. These cells are also found in the passages of the respiratory tracts and the digestive tracts.
---Sarcomas - soft tissue cancers. Soft tissue means: muscle, fat, blood vessels, nerves, lining of joints and tendons.
---leukaemias - cancer of the blood and bone marrow.
---Lymphoma - tumor of the lymphoid tissue. "lymphoid tissue" means a part of your body that protects against infection and disease (the immune system).
Cat Health and Cancer - Treatment
The treatment of cancer in cats has advanced significantly. Whereas in the past euthanasia would have been recommended for an older cat, there are now many options open to the veterinarian, cat and cat keeper. Surgery is the most common treatment. Although this doesn't always provide a cure it can allow for better analysis, follow up treatment for the cancer that remains and further surgery.
Another treatment is radiation therapy. This takes the form of several sessions of treatment over a 3-5 week period. Cats tolerate radiation therapy well apparently. This form of treatment is not always available, however.
Chemotherapy is another form of treatment for cat cancer. Chemotherapy is given (as is the case for humans) in the form of injections and/or tablets. Cats tolerate this form of treatment better than humans. The side effects for chemotherapy are lowered production of white blood cells (from bone marrow), some hair loss but this is confined to whiskers and stomach and intestine irritation. (source: Animal Health Trust, AHT, http://www.aht.org.uk)
Cat Health and Cancer - Some Causes
As stated these are largely unknown and there are many overlapping causes including environmental, genetic, nutritional, trauma and hormonal. Only a few cat cancers have known causes. The following causes are fairly well established:
---FeLV (FLV) - Feline Leukemia Virus. This disease is associated with cancer of the blood and bone marrow. FeLV is a serious illness.
---FIV (Feline Immunodeficiency Virus) increases the chance of getting cancer of the lymph system (lymphoid malignancies). An example of a cancer of the lymph system is lymphosarcoma. This cancer occurs in young adults.
---Genetic predispositions. There is a higher incidence of intestinal cancer that starts in the glands (intestinal adenocarcinoma) in Siamese cats.
---White cats (all white) are predisposed to getting skin cancer due to the reduced pigmentation in the skin, which provides reduced protection against the Ultra Violet element of sunlight. Clearly the white cat living indoors and outdoors in a sunny and hot climate is most at risk and steps should be taken to protect the cat. The susceptible areas are ears, nose (the areas not covered by fur).
---Chemicals can be carcinogenic
---Certain food additives may be carcinogenic. Cat food (opens to a list of posts on this subject) is a bit of a minefield. It is very commercial and there is less control over its manufacture as it is for cats. There is no easy answer. Wet food is better than dry generally.
---Hormones play a role in the development of cancer. For example, spayed females suffer a lower incidence of mammary cancer.
---Routine cat vaccinations can cause cancer. The most common form of cancer resulting from cat vaccinations and which resulted in changes is Feline Fibrosarcoma.
What we can do
---Checks - Put simply I think our duty is to inspect our cats regularly. This need not be arduous as it can be done when brushing, grooming or stroking our cats. Early treatment is the best for cancers obviously. Look for bumps, lumps and non-healing areas and if found go straight to the vet.
---Vomiting or loss of appetite for a day or more should be acted upon. This may be due to a cancer in the digestive system.
---Passive smoking - Cats like humans can contract cancer from passive smoking. It may be worse for a cat as the poisonous particles in cigarette smoke that kills people can sit on the cat's fur and skin where it will be licked of and ingested. This can lead to irritable bowel disease and possibly cancer.
---White cats - are more susceptible to skin cancer as mentioned. They should be kept in or under cover during periods of sunny weather and/or in the middle of the day when the sun is at its most fierce.
---Mouth face- swelling in the lips, jaw, neck, nose and mouth should be easy to see and acted upon quickly. The picture opposite is of course heartbreaking. This can must have been feral (taken in 2005 by sillydog) as it would have been spotted much earlier>>>>>>>>>>>>
---Respiratory system - Once again it should be obvious if our cat has a breathing problem and/or is coughing a lot or abnormally. I guess it is a bout being vigilant or simply aware of our cats needs etc.
---Desex - Spaying and neutering has many benefits to the domestic cat (although we are aware of the sad necessity of this procedure) one of which is to reduce the chance of contracting reproductive tract cancer.
---Inflammatory Bowl disease - this can lead to cancer of the gastrointestinal tract. The symptoms of bowl disease are diarrhea and vomiting. This should be obvious.
This list is not complete or comprehensive. It should go without saying that there is no substitute to seeing a veterinarian. This post is simply an overview by a concerned cat keeper.
Cat Health and Cancer to Home page
Photos (all published under a creative commons license -thank you all):
---Heading the post: This cat is called Fartamus by his keeper (the photographer). He developed a mast cell sarcoma. You can see it on the nose just to the left of his eye. The picture was taken in September of 2004. I hope the surgery proved successful. Thanks to McBeth for the license to publish the photo.
---Photo of white cat 1st down - this cat has no ears due to surgery to remove them as they were cancerous. He is a great cat. This is one of the beauties of cats, they are uncomplaining and patient. Photo by teddybear.crafts aka Mike
---Photo of white cat 2nd down - the photographer refers to the ears of this cat as possible signs of skin cancer. photo by nz lawyer.
Cat Health and Cancer - Sources:
- Medical sites (for definitions)
- Animal Health Trust
- Your Cat by Dr. Hodgkins