Fibrosarcomas are seen in younger dogs and rarely spread but they frequently recur locally after treatment.
Epulides are benign and, although they can grow to be quite large, present problems with eating, and sometimes ulcerate and bleed they are not life threatening. Epulides are cauliflower-type fibrous growths which occur along the gum margin (hence they are called "gingival cancer", and they are sometimes called periodontal fibrous hyperplasia). They are common in brachycephalic (short-nosed) breeds of dog, especially the Boxer and English Bulldog.
In general cancers occur more frequently with advancing age.
Young dogs, however, frequently develop warts in the mouth and on the tongue and these are cause by papilloma virus and the warts themselves are benign.. The warts can affect eating and sometimes localised secondary infection can occur giving a foul smell on the breath, but the disease is not serious and is self-limiting, lasting only about 6-12 weeks.
In other cases the type of tumour-type will not be obvious and accurate diagnosis will rely on histological examination of a biopsy, or removed tumour.
In all cases it is important to examine local lymph nodes in the throat or neck to detect evidence of spread. Enlargement or pain can be detected by feeling the site, but an Xray of the neck may be needed to identify retropharyngeal spread. An enlarged retropharyngeal lymph node is seen as a large soft tissue mass under the cervical spine, often displacing the windpipe (trachea) and gullet (oesophagus).
A chest Xray is very important to ensure that spread to the lungs has not occurred.
Any evidence of spread is a poor prognostic indicator which may affect the method(s) of treatment used. Ensuring a satisfactory quality of life is often more important than prolonging life in patients with advanced metastatic disease.
Excision is recommended for benign cancers - e.g. warts, and epulides - though the latter frequently recur.
Radiotherapy is recommended for oral squamous cell carcinomas and the prognosis is good.
Squamous cell carcinoma of the tonsil in older dogs however, is a much more serious form of cancer because it often spreads to the retopharyngeal lymph nodes and frequently spreads further to the lungs.
Combination therapies are usually advocated for the malignant tumours.