Loss of taste sensation may occur with advancing age but there is no evidence that
this is a common problem in cats and dogs. The likely effects of such a loss would
be reduced appetite and some authors have described malnutrition in surgical cases
involving the nasal passages.
Neoplasia of the tongue is uncommon in dogs, but there is a relatively high incidence
in cats. In the cat most neoplasms are squamous cell carcinoma, and others include
fibrosarcoma, papilloma and haemangioma. In dogs malignant melanoma is the most serious
as it is highly malignant, the fibrosarcoma and squamous cell carcinoma are also
seen. All carry a poor prognosis. If localised surgical excision may be possible
(e.g. papillomas) and in cats radiotherapy has been suggested as the best treatment
for squamous cell carcinoma. Some haemangiomas are corticosteroid responsive, but
there is no satisfactory treatment for fibrosarcoma though radiotherapy or hyperthermia
may be helpful in some cases.
Ulceration around the lingual margin and severe halitosis is associated with advanced
uraemia due to renal failure.