Skin Cancer in Cats

Posted by Lianne McLeod D.V.M. on

Skin Cancer in Cats

Skin cancer, a prevalent health issue in cats, is a topic of significant concern for pet owners and veterinarians alike.  Comprehending the different kinds of feline skin cancer, their sources, indications, and treatment choices is vital for early identification and competent control of this disease. 

This article will provide a thorough breakdown of skin cancer in cats, highlighting the significance of early awareness and prompt mediation.

Types of Skin Cancer in Cats

Skin cancer in cats can take several forms, each with distinctive qualities.  The following elaborates on the prevalent types of the malady that afflict cats.

Squamous Cell Carcinoma

Squamous Cell Carcinoma is one of the most common types of cat skin cancer.  It emerges from the epidermal cells, which are a variety of skin cells that create the external layer of the feline's epidermis.  SCC commonly manifests itself as a diminutive, firm lump on the dermis that gradually increases in magnitude.  Eventually, the cancerous growth can become necrotic, leading to the cat's discomfort.

SCC is particularly prevalent in cats with light-colored fur, as they are more susceptible to damage from sun exposure.  The areas most commonly in affected cats are those with minimal fur coverage, such as the ears, nose, and eyelids.

light fur cat, sun exposure

Basal Cell Tumors

Basal Cell Tumors are benign growth of blood lesions which originate in the basal cells found in the dermis, the outermost layer of the skin.  These growths are usually slow-moving and don't travel to other parts of the body, making this tumor less aggressive compared to other types of cutaneous skin cancer.

These benign tumors typically appear as solitary lumps on the skin’s surface.  They can vary in size and may have a central depression.  Despite being benign, Basal Cell Tumors can cause discomfort if they grow large or are located in areas where they interfere with the cat’s normal activities.

Mast Cell Tumors

Mast Cell Tumors are formed from mast cells, a type of white blood cell involved in the body’s immune response.  These tumors can be benign or malignant, and they often appear as small, itchy bumps on the skin.

Mast Cell Tumors can range greatly in their aspect, making it challenging to diagnose based on visual examination alone.  Such tumors are non-malignant formations that can appear in any part of the body, usually on the head, neck, and torso.

mast cell information

Soft Tissue Sarcomas

Soft Tissue Sarcomas are a group of malignant tumors that arise from the connective tissue or supportive tissues in the body.  These include soft tissues like fat, muscle, and fibrous tissue. They can be aggressive and spread to other body parts, including the lymph nodes.  These tumors typically appear as firm, subcutaneous masses that are attached to the underlying tissue. They can grow quite large and often recur after surgical removal.

Causes of Skin Cancer in Cats

Understanding the triggers of skin cancer in cats is paramount for protecting them from skin tumors and spotting them early on.  Although the precise causes are often indiscernible, several elements have been distinguished that can amplify a cat's risk of contracting skin cancer.

causes of skin cancer in cats

Sun Exposure

Prolonged sun exposure can lead to solar dermatitis, a condition that can progress to skin cancer if left untreated. The sun plays a key role in what causes certain types of skin cancer in felines, predominantly Squamous Cell Carcinoma.  Cats with light-colored or white fur are especially prone to squamous cell carcinomas because their skin has less melanin, the pigment that provides some protection against the sun’s harmful UV rays.

Areas of the body with sparse fur, such as the ears, eyelids, and nose, are most commonly affected by UV rays.  Limiting your cat’s exposure to the sun, especially during peak UV intensity hours, can help reduce the risk.

Genetic Factors

Genetic factors can also contribute to a cat’s increased risk of developing skin cancer. Certain breeds appear to be more prone to specific types of skin cancer. For instance, Siamese cats are more likely to develop Mast Cell Tumors. However, more research is needed to fully understand the genetic predispositions to skin cancer in cats.


Age is a potential threat factor for skin cancer among felines.  As cats age, the likelihood of skin neoplasms increases, with the most occurrences registered in mature and aging cats.  Cat's skin cancer is likely because of the cumulative effect of too much exposure to UV radiation from the sun and other external influences with the passing of time. Regardless of that, it is critical to note that skin cancers can take place in cats regardless of age.

Physical Trauma

Physical trauma to the skin, such as a wound or injury, can sometimes lead to the development of skin cancer, particularly in the case of soft tissue sarcomas.  Scientists have hypothesized that the inflammation and cell proliferation that occur during the healing process can sometimes lead to abnormal cell growth and cancer.  However, this topic is still under scrutiny and more research will be needed for it to be considered a hard fact. Nevertheless, ensuring that wounds are properly treated and healed can help reduce this risk.

The Prognosis for Cats with Skin Cancer

The prognosis for cats with skin cancer varies widely, depending on the type and stage of the cancer, as well as the cat’s overall health.  Early detection and treatment of most skin cancers can significantly improve the prognosis.  Some types of skin cancer, such as basal cell tumors, are typically slow-growing and have a good prognosis when treated at early stages.  However, more aggressive types of cancer, such as soft tissue sarcomas, can have a more guarded prognosis.

While we cannot completely eliminate the risk of skin cancer in cats, understanding these risk factors can help in its prevention.  Regular veterinary check-ups are crucial for early detection and treatment, as changes in your cat’s skin can often be the first sign of this disease.

Symptoms of Skin Cancer in Cats

Recognizing the symptoms of skin cancer in cats is crucial for early detection, accurate diagnosis, and treatment.  While symptoms can vary depending on the type of cancer, there are several common signs that cat owners should be aware of.

Common Symptoms

  1. Unusual Lumps or Growths: One of the most noticeable signs of skin cancer in cats is the presence of unusual lumps or growths on the skin.  These can vary in size, shape, and color, and may appear anywhere on the body.

  2. Changes in Skin Color or Texture:  Changes in the color or texture of your cat’s skin can be a sign of skin cancer.  This change could include areas of skin that are darker or lighter than normal, or skin that has become rough, scaly, or ulcerated.

  3. Hair Loss:  Hair loss in the area of a growth or lump is another common symptom.  This symptom can often be accompanied by itching or discomfort.

  4. Non-Healing Sores or Wounds:  Sores or wounds that do not heal, or that heal and then reopen, can be a sign of skin cancer.

Symptoms Vary Depending on the Type of Cancer

The symptoms of skin cancer in cats can vary widely depending on the type of cancer.  For example, Squamous Cell Carcinoma often appears as a small, hard lump that can become ulcerated over time.  On the other hand, Mast Cell Tumors can cause small, itchy bumps on the skin, while Soft Tissue Sarcomas typically appear as firm, subcutaneous masses.

Symptoms of Advanced Cases

In advanced cases of skin cancer, cats may exhibit additional symptoms such as lethargy, loss of appetite, and weight loss. The presence of these symptoms in older cats usually indicates that the cancer has progressed and may have spread to other parts of the body.

Diagnosis and Treatment of Skin Cancer in Cats

Diagnosing and treating skin cancer in cats involves a combination of physical examination, diagnostic tests, and various treatment modalities.  The following section provides a detailed overview of the process.

treatment of skin cancer in cats

Diagnostic Process

The diagnostic process for skin cancer in cats typically begins with a thorough physical examination.  The veterinarian will examine the cat’s skin for any unusual lumps, bumps, or changes in color or texture.  If an abnormal growth is found, further diagnostic tests may be required to confirm the diagnosis.

One common diagnostic test is a fine needle aspiration, where a small sample of skin cells is collected from the lump using a needle.  This sample is then examined under a microscope to look for cancerous cells.  In some cases, a surgical biopsy may be performed to obtain a larger tissue sample.

Additional diagnostic tests, such as blood tests, X-rays, or ultrasounds, may be performed to assess the cat’s overall health and to check if the cancer has spread to lymph nodes or other parts of the cat's immune system or body.

Treatment Options

Treatment options for feline skin cancer only in cats depend on the type and stage of the feline skin cancer itself, as well as the cat’s overall health. They include:

  • Surgical Removal:  This option is often the first line of treatment for many types of skin cancer.  The goal is to remove the entire tumor, along with a margin of healthy tissue around it, to ensure that all cancerous cells are removed.

  • Radiation Therapy: This may be recommended in cases where surgical removal is not possible or if the cancer has spread to other parts of the body.  Radiation therapy uses high-energy rays to kill cancer cells and shrink tumors.

Other treatment options may include chemotherapy, immunotherapy, or targeted therapies, depending on the type of cancer and the cat’s individual circumstances.

Prevention of Skin Cancer in Cats

While it’s not always possible to prevent skin cancer in cats, understanding the risk factors and taking preventative measures can help reduce your cat’s risk.  Here are some tips for reducing a cat’s risk of developing skin cancer:

prevention of skin cancer in cats
  1. Limit Sun Exposure:  Cats with light-colored fur or hairless cats are at a higher risk of developing skin cancer when exposed to excessive UV light.  Limiting your cat’s exposure to the sun, especially during peak UV intensity hours, can help reduce the risk.

  2. Provide Sun Protection:  Consider providing shaded areas for your cat to rest and play in, especially if they have access to the outdoors during the day.  Sunscreen formulated specifically for pets can also be used for furless cats, but always consult with your vet before applying any products to your cat’s skin.

  3. Regular Grooming:  Regular grooming can help you spot any unusual lumps, bumps, or changes in your cat’s skin early.  This step is particularly important for long-haired breeds where changes in the skin may not be immediately visible.

  4. Healthy Diet and Lifestyle:  A balanced diet and regular exercise can help maintain your cat’s overall health and strengthen their immune system, which can help protect against cancer.

In Conclusion

Regular veterinary check-ups are crucial for early detection of skin cancer in cats.  Your vet can perform a thorough physical examination and check for any signs of your cat's skin cancer.  Regular check-ups allow for early detection and treatment, which can significantly improve the prognosis for those cats diagnosed with skin cancer. 

With early detection and appropriate treatment, many cats with skin cancer can continue to live a good quality of life.  Don’t wait until it’s too late - your furry friend’s health is in your hands. Schedule a vet check-up today and stay vigilant for any changes in your cat’s skin. Your cat’s health is worth it!


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Lianne McLeod, DVM, is a former writer for The Spruce Pets, contributing articles for 11 years. Before Dr. McLeod began writing about pet care, she worked several years in small animal practice. She has written extensively about the care and keeping of exotic pets and pet health care. She now researches water quality and chronic disease at the University of Saskatchewan. Lianne McLeod earned her Doctorate of Veterinary Medicine from the Western College of Veterinary Medicine at the University of Saskatchewan. She also received a Bachelor of Science degree in biology from Simon Fraser University. She continued her education and received a Ph.D. in Epidemiology from the University of Saskatchewan. Now, she splits her time between her family, research and writing about pet health for all the animal lovers out there.
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