Understanding Oral Squamous Cell Carcinoma in Cats: Causes, Symptoms, and Treatment Options

Posted by By Mukesh Pathak 9 Min Read

Oral Squamous Cell Carcinoma (OSCC) is the most common type of oral cancer in cats, accounting for 60-70% of all oral tumors. This aggressive cancer originates in the squamous cells, which are the flat cells lining the oral cavity. OSCC can invade surrounding tissues, including bones and lymph nodes, making early detection and treatment crucial for managing the disease.

In this article, we will explore the causes, symptoms, diagnosis, and treatment options for Oral Squamous Cell Carcinoma in cats, helping you understand how to recognize and address this serious condition.

Causes of Oral Squamous Cell Carcinoma in Cats

The exact cause of OSCC in cats is not fully understood, but several factors have been associated with its development:

  1. Environmental Toxins: Exposure to tobacco smoke, flea collars, and other environmental pollutants has been linked to a higher risk of developing OSCC. Cats living in households with smokers are particularly susceptible due to their frequent grooming, which may expose them to carcinogens.
  2. Chronic Inflammation: Long-term inflammation in the oral cavity, often caused by dental disease, can lead to cellular changes and potentially cancerous growth. Dental infections or poor oral hygiene may contribute to this process.
  3. Dietary Factors: Some studies suggest that a diet high in canned food, particularly fish-based varieties, may increase the risk of OSCC in cats, although this link remains controversial.
  4. Genetic Predisposition: Although less common, certain cats may have a genetic susceptibility to developing oral cancers, including OSCC.
  5. Viral Infections: Feline papillomavirus, a virus that can cause warts in cats, has been associated with some cases of squamous cell carcinoma, though this is not a primary cause.

Symptoms of Oral Squamous Cell Carcinoma in Cats

The symptoms of OSCC in cats can vary depending on the tumor’s location and size. Often, the signs are subtle in the early stages but become more pronounced as the disease progresses. Common symptoms include:

  1. Difficulty Eating: Cats with OSCC often struggle to eat due to pain or difficulty chewing. They may drop food, chew on one side of the mouth, or refuse to eat hard food altogether.
  2. Weight Loss: Due to a reduced appetite, affected cats may lose weight, become lethargic, or show signs of malnutrition.
  3. Oral Mass: A visible mass or swelling in the mouth is a hallmark symptom of OSCC. These masses are typically located on the gums, tongue, or palate and may appear red, ulcerated, or infected.
  4. Excessive Drooling: Cats with OSCC often drool excessively, sometimes with blood present in the saliva. This is a result of the tumor irritating the tissues in the mouth.
  5. Bad Breath: Halitosis, or bad breath, is a common symptom of OSCC due to infection and tissue breakdown associated with the tumor.
  6. Facial Swelling: In advanced cases, the tumor may invade the jawbone or surrounding tissues, causing visible facial swelling or deformity.
  7. Loose Teeth: The tumor can affect the stability of teeth, leading to loose or missing teeth, especially in cases where the cancer has spread to the jawbone.
  8. Pain and Discomfort: OSCC is a painful condition, and cats may show signs of discomfort by pawing at their mouths, becoming irritable, or avoiding physical contact.

Diagnosis of Oral Squamous Cell Carcinoma in Cats

Accurate diagnosis of OSCC requires a combination of clinical examination and diagnostic tests. Your veterinarian will typically follow these steps:

  1. Physical Examination: The vet will conduct a thorough examination of your cat’s oral cavity, looking for any masses, swelling, or other abnormalities. If OSCC is suspected, further testing will be necessary.
  2. Biopsy: A biopsy is the definitive way to diagnose OSCC. A small tissue sample from the tumor is taken and sent to a pathologist for microscopic examination to confirm the presence of cancerous cells.
  3. Imaging Studies: X-rays or CT scans are often used to determine the extent of the tumor and whether it has invaded nearby structures, such as the jawbone. These imaging studies can also help detect metastasis to the lungs or lymph nodes.
  4. Blood Tests: Routine blood work, including a complete blood count (CBC) and chemistry panel, can provide insight into your cat’s overall health and help identify any underlying conditions that may complicate treatment.
  5. Lymph Node Aspiration: If the cancer is suspected to have spread to nearby lymph nodes, a fine needle aspiration (FNA) may be performed to collect cells from the lymph nodes for analysis.

Treatment Options for Oral Squamous Cell Carcinoma in Cats

The treatment of OSCC in cats is challenging due to the aggressive nature of the cancer and its tendency to invade nearby tissues. A multi-modal approach, involving surgery, radiation therapy, and palliative care, is often necessary. The choice of treatment depends on the size and location of the tumor, as well as the overall health of the cat.

1. Surgical Removal

  • Indication: Surgery is the primary treatment for OSCC, especially if the tumor is localized and has not spread extensively.
  • Procedure: The goal is to remove the tumor along with a margin of healthy tissue to reduce the risk of recurrence. In some cases, partial removal of the jawbone (mandibulectomy or maxillectomy) may be necessary to achieve clean margins.
  • Challenges: Complete surgical removal is difficult, especially for tumors located on the tongue or other critical areas, and recurrence is common.

2. Radiation Therapy

  • Indication: Radiation therapy is often used either as a primary treatment for inoperable tumors or as an adjunct to surgery to target any remaining cancerous cells.
  • Procedure: High-energy radiation beams are directed at the tumor to destroy cancer cells. Radiation is often used to manage symptoms and slow the progression of the disease in cases where surgery is not possible.
  • Side Effects: Side effects may include skin irritation, mouth ulcers, and temporary difficulty eating.

3. Chemotherapy

  • Indication: Chemotherapy is not highly effective in treating OSCC, but it may be used in combination with other treatments, especially in advanced cases or when the cancer has spread.
  • Drugs Used: Common chemotherapy agents for OSCC include carboplatin and doxorubicin. Chemotherapy is more commonly used for palliation rather than curative purposes.
  • Side Effects: Side effects in cats are generally mild but can include nausea, vomiting, and a temporary drop in white blood cell counts.

4. Palliative Care

  • Indication: In cases where the cancer is too advanced for curative treatment, palliative care focuses on managing symptoms and improving the cat’s quality of life.
  • Care Options: Pain management is a primary focus, and medications such as opioids or nonsteroidal anti-inflammatory drugs (NSAIDs) may be prescribed. Nutritional support and soft food diets may also be necessary.

Prognosis of Oral Squamous Cell Carcinoma in Cats

The prognosis for cats with OSCC is generally poor, particularly for tumors that are large or have invaded surrounding tissues at the time of diagnosis. Median survival times range from 2 to 6 months, even with aggressive treatment. However, early detection and intervention can improve outcomes. Cats treated with a combination of surgery and radiation therapy may have better survival times, but recurrence is common.

Importance of Early Detection

Early detection of OSCC is critical for improving treatment success. Regular veterinary check-ups and monitoring for any changes in your cat’s eating habits, behavior, or oral health are key to catching the disease in its early stages. If you notice any signs of discomfort, swelling, or masses in your cat’s mouth, prompt veterinary attention is essential.