Squamous cell carcinoma (SCC) is the most common oral (mouth) tumor in cats and typically affects middle-aged to older cats. Factors that may increase the risk of oral SCC include flea collars, high volumes of canned food, and household smoke exposure; however, there is no one factor that is known to cause SCC. Unfortunately, oral SCC is an aggressive locally invasive tumor that is difficult to control. Oral SCC appears to have a low rate of spread to other sites (metastasis) but this may be simply due to the short survival times following diagnosis.
Most cats are examined by their veterinarian following identification of an oral mass or swelling by the owner. Oral SCC in cats typically:
Other symptoms can include:
Diagnosis of oral SCC requires a biopsy of the tumor often with the cat under general anesthesia so that a good sample of the tumor can be collected. A thorough oral examination can be performed at the same time, and the tumor is typically measured and documented along with the location.
While not diagnostic for SCC, the diagnostic work-up includes:
For some tumors, particularly those located in the front of the upper jaw (maxilla) or lower jaw (mandible), advanced imaging with computed tomography (a CT scan) may be recommended.
Adjusting the consistency of the food (from kibble to canned stewed diets to canned soft or gruel diets) can help ensure whichever form is easiest for the pet to ingest is available. Non-steroidal anti-inflammatory drugs can be useful in managing discomfort. Furthermore, the use of pain relievers should be a focus of therapy to reduce discomfort for the patient.
The prognosis for cats with oral SCC is poor and most cats will have survival times ranging from 3 to 6 months. Cats with small tumors located on the lower jaw (mandible) that are treated with surgery have a better chance of surviving for one year particularly if the mass can be completely removed.
Christine Swanson, DVM, DACVIM (Oncology)