Oral squamous cell carcinoma (OSCC) is one of the most common types of cancer that affects the mouth in dogs. It arises from the squamous cells lining the oral cavity and can cause significant health problems, including pain, difficulty eating, and, if left untreated, a reduced quality of life and eventual life-threatening complications.
What is Oral Squamous Cell Carcinoma (OSCC)?
Oral squamous cell carcinoma is a malignant (cancerous) tumor that originates in the squamous epithelial cells, which are found in the tissues lining the mouth, gums, and tongue. OSCC is aggressive and tends to invade local tissues quickly, but it can also metastasize to distant organs, including the lymph nodes and lungs.
Causes and Risk Factors
The exact cause of OSCC in dogs is not fully understood, but several factors may increase the likelihood of developing this type of cancer:
- Age: OSCC is most commonly seen in older dogs, usually over the age of 10.
- Breed: Certain dog breeds, including the Scottish Terrier, Boxer, Chow Chow, and Beagle, are predisposed to developing oral cancer.
- Tobacco smoke exposure: Dogs exposed to secondhand smoke from cigarettes may have a higher risk of developing oral cancers.
- Chronic inflammation or irritation: Conditions that cause chronic irritation in the mouth, such as dental disease or poorly fitting dentures, may increase the risk.
- Dietary habits: Dogs that eat a poor diet or have a habit of chewing on hard objects might be at a higher risk of oral cancers, although this is less clearly established.
Symptoms of Oral Squamous Cell Carcinoma
The symptoms of OSCC can vary depending on the size and location of the tumor. Common signs that may indicate oral squamous cell carcinoma in dogs include:
- Bad breath (halitosis): One of the early signs of oral cancer can be persistent bad breath that doesn’t go away with regular dental care.
- Mouth pain: Dogs with oral squamous cell carcinoma may show signs of pain when chewing or opening their mouth. They might paw at their face or drool excessively.
- Difficulty eating: Dogs with oral tumors may have difficulty eating, particularly dry food or large pieces. They may begin to chew on one side of their mouth and have difficulty picking up food.
- Visible mass or swelling in the mouth: A lump or swelling inside the mouth, gums, tongue, or roof of the mouth can be a sign of OSCC.
- Bleeding from the mouth: Tumors in the mouth can bleed, leading to blood in saliva or on the food and water bowls.
- Weight loss: As the disease progresses, dogs may lose weight due to difficulty eating or the cancer’s systemic effects.
- Limping or swollen lymph nodes: If the cancer spreads to the lymph nodes, you may notice swollen lymph nodes near the jaw or neck.
Diagnosing Oral Squamous Cell Carcinoma
If you notice any of the signs mentioned above, it’s important to take your dog to a veterinarian for a thorough examination. The veterinarian may use the following diagnostic techniques:
- Oral examination: A thorough examination of the dog’s mouth is essential. The vet will look for any abnormal growths or masses.
- Biopsy: A tissue sample is taken from the suspected tumor to confirm the diagnosis. This can be done through a fine needle aspiration (FNA) or surgical biopsy.
- X-rays or CT scans: Imaging studies, such as X-rays or CT scans, can be used to assess the extent of the tumor and whether it has spread to nearby bones or organs.
- Blood tests: Blood tests may be done to check for signs of infection or other abnormalities that could indicate the cancer’s progression.
Treatment Options for Oral Squamous Cell Carcinoma
The treatment for OSCC depends on the tumor’s size, location, and whether it has spread. The most common treatments for oral squamous cell carcinoma in dogs include:
- Surgery: If the tumor is localized and has not spread, surgical removal is the most effective treatment. This may involve removing part of the jaw or other affected tissues. Surgery is often combined with radiation therapy to ensure that the cancerous cells are fully treated.
- Radiation therapy: Radiation can help shrink the tumor and alleviate pain, especially if surgery is not an option. It is often used when the tumor cannot be surgically removed or when the tumor has spread to other areas.
- Chemotherapy: Chemotherapy is sometimes used as an adjunct to surgery and radiation, particularly if the cancer has spread to other parts of the body. Chemotherapy drugs may be administered orally or via injection to target cancer cells throughout the body.
- Palliative care: In some cases, especially when the cancer has spread or surgery is not an option, palliative care may be the best option. This can include pain management, nutritional support, and medications to help maintain quality of life.
Prognosis
The prognosis for dogs with oral squamous cell carcinoma depends on several factors, including the tumor’s location, size, and whether it has spread. Unfortunately, OSCC tends to be aggressive, and many dogs with this condition are diagnosed at an advanced stage. The prognosis for dogs with localized OSCC who undergo surgery or radiation therapy is generally more favorable. However, if the cancer has metastasized, the prognosis may be poor, with a survival time of only a few months.
- Localized OSCC: If caught early and the tumor is small, dogs may have a good chance of recovery with surgery or radiation therapy.
- Metastatic OSCC: If the cancer has spread, the prognosis becomes much less favorable, and treatment is typically focused on palliation rather than a cure.
Preventing Oral Squamous Cell Carcinoma
While it’s not always possible to prevent oral squamous cell carcinoma, there are some steps you can take to reduce your dog’s risk:
- Regular dental care: Brushing your dog’s teeth regularly and scheduling professional dental cleanings can help reduce the risk of oral disease, which may contribute to the development of cancer.
- Avoid tobacco smoke exposure: Keep your dog away from environments where they might be exposed to tobacco smoke, as this is a known risk factor for oral cancers.
- Healthy diet and exercise: A balanced diet and regular exercise can help keep your dog healthy and reduce the risk of many health conditions, including some cancers.
Conclusion
Oral squamous cell carcinoma in dogs is a serious condition that requires prompt attention. If you notice any signs of oral tumors or mouth pain in your dog, seek veterinary care immediately. Early diagnosis and treatment can improve the chances of a successful outcome. Whether through surgery, radiation, or palliative care, working closely with your veterinarian will help you make the best decisions for your dog’s health and well-being.
