Cancer is a major cause of death in cats, especially as they get older. As in humans and dogs, cancer in cats arises due to the uncontrolled growth and division of abnormal cells. At mybestie.gr, we are of the opinion that knowledge about the different types of cancers, their location in the body, the causes of cancers, and their treatments can empower pet owners to take proactive measures for their cat’s health.

How cancer arises in cats

Cancer arises due to the failure of the normal regulatory mechanisms of cells. The cells start dividing even when there is no need for more cells, resulting in the development of tumors or the spread of cancer cells throughout the body. Not all tumors are cancerous, but many can cause the malfunctioning of organs or spread to other tissues, a process known as metastasis.

The causes of cancer in cats are still not well understood, but studies have indicated that genetic, environmental, viral, and lifestyle factors are some of the causes. Older cats are more likely to develop cancer. Viruses such as the feline leukemia virus (FeLV) have been shown to be a major cause of cancer in cats.

Common cancers in cats and where they develop

Cancer in cats can develop from many different organs or tissues, but the following are some of the most common ones:

1. Lymphoma

This is one of the most common cancers found in cats. It develops from the lymphocytes, a type of white blood cell, and can develop in the lymph nodes and organs like the intestines, liver, and spleen. Gastrointestinal lymphoma is the most common form of this cancer in cats, which leads to weight loss, vomiting, and diarrhea.

2. Mammary (breast) cancer

This cancer is most common in unspayed female cats. Mammary tumors in cats are usually very aggressive. This risk can be greatly reduced by spaying the cat at a young age.

3. Skin tumors

Skin cancers can develop anywhere on the body. Some skin cancers are sun-induced (especially on light-colored or thin skin), while others develop from chronic wounds or inflammation.

4. Oral tumors

These cancers include squamous cell carcinoma and fibrosarcoma, which develop in the mouth and throat. They may cause bad breath, eating difficulties, or drooling.

5. Bone cancer (osteosarcoma)

Osteosarcoma is more common in dogs, but it can also develop in cats. It develops in the bones and leads to lameness or swelling.

Causes and risk factors

Cancer is not caused by one thing, but several risk factors can be identified:

• Viral infection: FeLV and possibly FIV (feline immunodeficiency virus) make cats susceptible to cancer.
• Genetic predisposition: Certain breeds or families are more at risk.
• Age: Middle-aged and older cats are more likely to get cancer.
• Hormonal factors: Reproductive hormones influence the risk of mammary cancer.
• Hronic inflammation or injury: Chronic irritation can cause mutations in cells over time.
• Diet and environmental toxins: These are thought to be possible risk factors in cats, although not as well-proven as in humans.

How cancer is diagnosed

Diagnosis usually starts with symptoms and physical examination. Vets may employ:

• Blood tests to evaluate organ function.
• X-rays or ultrasound to detect tumors.
• Fine Needle Aspirates or biopsies to study cells under a microscope.
• PET or CT scans in specialized veterinary centers to evaluate how far the cancer has progressed.

Early diagnosis, especially in at-risk cats, can often result in a more successful outcome.

Treatment methods: From surgery to modern therapies

Feline cancer treatment depends on the type, location, and stage of cancer, as well as the cat’s health status.

Surgery

Generally the preferred treatment for localized tumors. Early tumor removal can be very effective for conditions like early-stage mammary cancer or skin tumors.

Chemotherapy

For cancers that have spread or cannot be surgically removed. Although cats are more tolerant of chemo than dogs or people, treatment is kept to a minimum to avoid adverse reactions.

Radiation therapy

Useful for some oral cancers or cancers that are difficult to surgically remove in their entirety.

Immunotherapy and targeted therapy

These are relatively new modalities that use the cat’s immune system to attack cancer cells or specifically target cancer cell pathways. These modalities are being used increasingly in veterinary cancer centers.

Palliative care

When a cure is not an option, treatment may aim to improve the cat’s quality of life, including managing pain, stimulating appetite, and ensuring the cat remains comfortable.

The role of regular visits to the vet

Because the early symptoms of cancer in cats can be quite subtle, such as weight loss, loss of appetite, lethargy, or changes in behavior, regular visits to the vet are a huge benefit. In older cats or in breeds that are prone to cancer, more frequent checks can be beneficial.