Canine Tongue Cancer
" Canine tongue cancer is an oral cancer that is uncommon in dogs. Squamous cell carcinoma is the most common type of tongue cancer in dogs, but other types such as fibrosarcoma, malignant melanoma, mast cell tumor, lymphosarcoma and hemangiosarcoma have been reported, but as secondary metastasized cancers (spread from other areas of the body). Clinically, a patient with canine tongue cancer usually finds it difficult to eat, drink, and swallow. An affected dog may experience severe pain in the oral cavity, with bloody saliva continually flowing from the mouth. In advanced stages of the disease, a dog will be unable to keep its mouth closed, and will feel difficulty breathing due to a blockage of the oral path by swelling of the tongue. A biopsy of cancerous tissue and x-rays can confirm the presence of the disease, while type of cancer should be identified carefully, as almost all types of are malignant (cancerous, fast spreading) in nature. Surgical excision of cancerous tissues and chemotherapy can be effective if the cancer is in its initial stages. Otherwise the prognosis is termed “Very Poor”, and the dog may not survive for more then a year. "
Symptoms of Canine Tongue Cancer:
Initially, a dog with tongue cancer will find it hard to drink or eat. The tongue will appear to redden due to an increase in the blood supply, but it should be noted that no significant morphological changes (noticeable) have been reported clinically during the early stages of the disease. Most dog owners and even veterinarians couldn’t identify this change as cancerous development, as it indicates an oral inflammation.
As the disease progresses, symptoms appear more rapidly, and the dog becomes completely anorectic (loss of appetite) due to the dog feeling uncomfortable while swallowing food, water or saliva. Bloody saliva flows from mouth continuously.
In very advanced stages, the size of the tongue increases rapidly due to severe inflammation and a rapid growth of malignant cancerous tissues. Canine tongue cancer can spread to the gums and downwards into the pharynx. Due to the increased size of the tongue and involvement of the epiglottis, larynx and pharynx, a dog may experience difficulty breathing.
Diagnosis of Canine Tongue Cancer:
Confirmation of any cancerous development is purely based upon taking a biopsy of the oral tissues. Since most dog tongue cancers are malignant (cancerous) in nature, it is highly recommended that x-rays of the thorax be made.
Malignant cancer spreads rapidly to other parts of the oral cavity and deeper into the respiratory and digestive system. Also, due to the lymphatic supply deep in the walls of the oral cavity, nasal passage, salivary glands, larynx and esophagus, it is recommended to conduct a thorough biopsy of these parts as well.
Treatment of Canine Tongue Cancer:
Surgery is the treatment of choice for dog tongue cancer if surgical margins do not exceed 1 – 2 cm. There is a chance of recurrence after the 1st surgery if the surgical margins exceed the recommended limits for the reason that it is not only hard to operate extended margins, but also precision can never be guaranteed.
A repeat surgery is another treatment option to remove sporadic distribution of cancerous tissues. Extensive post surgical care is usually required, along with strict monitoring of any recurrence. Chemotherapy and the application of radiation can be combined with the surgical option, and the medication mitoxantrone.
Chemotherapy and surgery severely affect the health status of the dog, thus it is required to keep dog under constant monitoring. Nutritional and fluid supplementation should be continued even after recovery, for at least 6 months. Supplements used should contain components which help in the gradual excretion of chemotherapeutic residues. Herbal preparations such as C-Caps Formula can help in this regard, but are used only for support, after recovering from surgery, to promote the dog's health and eliminate toxins from the body.
Prognosis:
If timely and precise treatment is applied during the initial stages of the disease, there is a good chance that a complete recovery will be achieved. In the advanced stages, the prognosis for patients of canine tongue cancer is termed, “Very Poor” due to rapid metastasis (spread of the cancer). Such dogs usually do not survive for more then one year.
References:
W. B. Morrison, “Cancer in dogs and cats: medical and surgical management” (Teton NewMedia, 2002)
Merck Veterinary Manual (Merck & Co. 2008)
Washington State University College of Veterinary Medicine
