Nose and Sinus Cancer (Squamous Cell Carcinoma) in Dogs

Squamous cell carcinoma is cancer of squamous cells, or epithelial cells, which are located in the skin’s epidermis. This type of carcinoma can also be present in the lungs, digestive lining, and other areas of the dog’s body. In the nose and sinus areas, the tissues are affected as a result of the rapid multiplication of abnormal cells.

Squamous cell carcinoma in the nose and sinus in dogs is an aggressive form of cancer. Even though the metastasis rate is low, the survival rate is at approximately fifty percent. Dogs that are more susceptible to this type of cancer are usually mid-to-older aged and larger breeds.

Nasosinal squamous cell carcinoma, or nose and sinus cancer, occurs as a result of one or more cancerous tumors rapidly growing in the nose and sinus areas of the dog.

Symptoms of nose and sinus cancer in dogs of the squamous cell type are easily seen, and if your dog exhibits any of these symptoms it is imperative to make an appointment with your veterinarian. Symptoms include:

• Nasal discharge, often bloody
• Mucus and pus discharge from the nose
• Bone erosion around the nose
• Shortness of breath
• Rapid and noisy breathing
• Sneezing
• Eye inflammation
• Eye discharge

Types

Nasal and sinus cancer in dogs is quite rare, comprising only two-percent of canines. Other nasal carcinomas that can affect canines are:

• Undifferentiated carcinoma
• Adenocarcinoma
• Fibrosarcoma
• Osteosarcoma
• Chondrosarcoma

The cause of nose and sinus cancer in canines is still being researched and is currently unknown. Studies do show that there are a few links to this type of cancer. Causes may include:

• Pollutants
• Exposure to combustion products (fossil fuels)
• Kerosene heater exposure
• Dog’s living in urban, polluted environments

If your dog is exhibiting any of the symptoms, please make an appointment with your veterinarian. The veterinarian will ask questions and look at his chart for any medical issues and medical history. He may ask you questions about the signs, such as about the onset and severity of the symptoms. 

He will do a physical exam and with that, will run tests to see how the bodily functions are performing. He will perform a complete blood profile, biochemistry profile, urinalysis, a clotting profile (for the biopsy), radiography of the nasal area and cavity, rhinoscopy, and cytology. These tests will give the medical professional much-needed information before proceeding on to the biopsy and CT scan, which will give the veterinarian a definitive diagnosis. 

In terms of the biopsy, there will be bleeding during this needed procedure, hence the clotting profile before the test. If there are platelet or clotting abnormalities, the veterinarian may need to investigate this abnormality further and see if it can be treated before moving on to the actual biopsy. The doctor will give you options on what can be done to get a sample of the affected tissue. The CT scan will give the veterinarian much more information about the tumor, and to help the doctor determine the proper dosage of radiation therapy when given.

Treatment of this aggressive form of cancer, as well as the location of the tumor, will need to be carefully considered by the veterinarian and you as well. Treatment options can include:

Chemotherapy

Chemotherapy may be performed if the medical professional sees fit. This solely depends on the severity of the condition. Combination chemotherapy may be also given as a method of treatment.

Surgery

Surgery can present quite a challenge due to the fact that the tumor is so close to the eyes and the brain; however, in some cases, rhinotomy may be performed. During this surgical procedure, there is an incision into the nose to attempt to remove part of the tumor. This is not a preferred method of treatment, because when a dog is diagnosed it is usually at a time when the cancer has advanced. Many of the tumors in the nose and sinus cavity are inaccessible or just too risky for the dog to have this procedure done. For those dogs that have had rhinotomy, the survival rate was at the maximum of five months.

Radiation 

Radiation is the preferred choice of therapy for dogs with nasosinal squamous cell tumors. This treatment can cover the entire nasal area; however, it does present itself with disadvantages. There are several side effects of radiation therapy, such as mouth inflammation and developing ulcers, inflammation of the eyes, severe runny nose, and cornea inflammation.  Harsher side effects can also occur later on, and can include, but not be limited to keratitis of the eye, cataracts, hemorrhage, seizures, brain death, fibrosis, and osteonecrosis. 

Medications

After radiation therapy, the dog is given medications, such as antibiotics and pain management drugs. If the dog had adverse side effects that harmed the mouth or esophagus during the radiation, a feeding tube may have to be inserted until the dog can heal. 

Brachytherapy

This therapy is implemented by the incorporation of a radioactive substance directly into the tumor of the nose or sinus of the dog.

Immunotherapy

Immunotherapy may be successful in treatment by stimulating the immune system.

It can be difficult to decide on whether the radiation therapy is worth it, as even with this therapy the dog’s lifespan is dramatically limited. Without any treatment, the prognosis is a few months at the most. Radiation therapy can prolong your companion’s life anywhere from eight months to a year and a half, so the choice will have to be made regarding quality of life without treatment versus after radiation therapy.