Gingival Squamous Cell Carcinoma in Dogs
Squamous cell carcinoma, a highly aggressive form of tissue cancer, can manifest in various body parts, including the oral cavity, in dogs. This type of cancer possesses the ability to rapidly metastasize throughout the body, often leading to dire outcomes. Among the diverse oral cancer types affecting dogs, squamous cell carcinoma stands as the most prevalent. These tumors exhibit swift growth and typically infiltrate adjacent bone and tissue. While unlike other carcinomas, they tend not to metastasize to other organs, they primarily afflict older dogs, typically around ten years of age. Nonetheless, instances of squamous cell tumors have been documented in dogs as young as three years old.
Symptoms and Types
- Excessive salivation
- Challenges in chewing and swallowing (dysphagia)
- Unpleasant mouth odor (halitosis)
- Presence of blood in the mouth
- Loss of weight
- Loosening of teeth
- Oral growths
- Altered or swollen facial structure
- Enlargement of lymph nodes resulting in swelling under the jaw or along the neck
Causes
No identifiable causes have been determined.
Diagnosis
To diagnose your dog’s condition, you must provide a detailed history of its health leading up to the appearance of symptoms. Your veterinarian will conduct a comprehensive physical examination, which includes collecting body fluid samples for laboratory analysis such as complete blood count, biochemical profile, and urinalysis to assess the normal functioning of internal organs. During the physical examination, your veterinarian will thoroughly inspect your dog’s oral cavity, paying close attention to loose teeth and any abnormal tissue growths. By palpating (examining through touch), your veterinarian can determine if the lymph nodes under your dog’s jaw and neck are enlarged, indicating the body’s response to disease (as lymph nodes produce white blood cells). If enlarged lymph nodes are present, your veterinarian may perform an aspiration needle procedure to extract fluid for analysis, helping to determine if the oral growth has spread to the lymph nodes. Additionally, x-rays of your dog’s chest and head will be ordered to assess whether the oral tumor has invaded nearby bone and tissue or spread to the lungs. A biopsy of the growth will also be necessary for a precise diagnosis of the tumor type.
Treatment
The treatment approach will be determined by the size of the growth in your dog’s mouth. If the growth is small and localized without spread to nearby bone or other areas, cryosurgery, a technique involving freezing, may be employed for removal. In cases of larger tumors, a more extensive surgical procedure may be required to excise the growth along with potentially affected bone or jaw tissue. Dogs typically recover well even after partial jaw removal.
Following surgery, your veterinarian might recommend radiation therapy to ensure complete elimination of cancer cells. Combining radiation therapy with surgery has shown to extend the lifespan of some dogs. In instances where surgical removal is not feasible due to the tumor’s size, radiation therapy and/or chemotherapy may be utilized for treatment. These modalities can be administered individually or in combination, with better outcomes often observed when both are used together. While some dogs may achieve remission with radiation and chemotherapy, it’s uncommon; more frequently, this treatment regimen slows tumor growth, thereby extending the dog’s life.
Photodynamic therapy, another treatment option for oral squamous cell carcinomas, involves a photosensitive cancer-killing agent activated by wavelengths from a surgical laser beam. This therapy aims to shrink the tumor and control its growth, thus alleviating your dog’s symptoms.
Living and Management
Following surgery, your dog will require hospitalization for several days. Your veterinarian will closely monitor its pain levels and ability to eat and drink independently before considering discharge for home care. Once home, your dog may experience mouth soreness, especially if part of its jaw has been removed, leading to difficulty in eating. Your veterinarian will assist you in devising a diet plan consisting of easily chewable foods until your dog adapts to the jaw bone loss. You may need to hand-feed your dog small portions of food until it can resume eating on its own. Pain management medication will be provided, and it’s crucial to adhere strictly to the prescribed dosage and schedule.
Even if surgery isn’t pursued, radiation therapy can cause mouth soreness, necessitating the feeding of soft foods during treatment. Dogs undergoing radiation therapy may develop mouth sores, leading to decreased appetite. Failure to eat or drink for several days can result in severe illness. If your dog cannot or refuses to accept liquid nourishment, hospitalization for intravenous (IV) nutrition may be necessary. Nausea is a common side effect of chemotherapy, further reducing your dog’s appetite. Your veterinarian will prescribe medications to alleviate nausea.
Recurrence is common with squamous cell carcinomas of the mouth, akin to carcinomas of other types. With surgery and radiation, some dogs can experience comfort for up to three years before recurrence.