Oral Squamous Cell Carcinoma in Cats
What is Oral Squamous Cell Carcinoma?
Oral squamous cell carcinoma is locally invasive, but it does not readily spread to other places in the body (called metastasis).
Diagnostic tests are recommended to determine which sites in the body are involved. These tests include:
- Complete blood count (CBC)
- Serum biochemistry panel
- Urinalysis (U/A)
- Regional lymph node evaluation
- Thoracic radiographs
The treatment of choice for a locally invasive oral tumor would ideally be complete surgical resection. Unfortunately, this is a difficult decision because of the often extensive nature of these tumors coupled with the relatively small jaw size of cats and their poorer tolerance to maxillectomy/mandibulectomy as compared to dogs. The use of radiation therapy could therefore be considered - ideally in conjunction with surgery or if that is not possible, then as single modality therapy. Again, results have been discouraging. In reports of cats treated with aggressive surgery or the combination of surgery and radiation therapy, median survival times are only approximately 2-4 months, although many of these cats may have had larger tumors in more difficult locations (such as sublingual). Even the addition of chemotherapy has failed to lead to significant improvements. In one group of cats treated with definitive radiation therapy and mitoxantrone chemotherapy, median survival time was 6 months with only 30% of cats surviving to one year.
Because of the lack of long-term tumor control in spite of aggressive therapy, another reasonable option to consider is palliative radiation therapy. Palliative radiation therapy consists of two consecutive days of twice-daily radiation treatments and is aimed at alleviating pain, inflammation, and swelling associated with the tumor. This treatment course is repeated in one month if no disease or symptom progression is noted.
We also recommend piroxicam, an oral Non-Steroidal Anti-Inflammatory Drug (NSAID) which has anti-inflammatory and analgesic properties as well as possible anti-tumor activity against carcinomas. This medication should be given with food and the pet owner instructed to watch for signs of gastrointestinal upset (vomiting, change in stool, etc.). If such signs develop, piroxicam should be discontinued for 3-5 days. Restarting of therapy can then be considered in conjunction with the stomach-protectant misoprostil.
- Reeves NCP, Turrel JM, Withrow SJ. Oral squamous cell carcinoma in the cat. J Am Anim Hosp Assoc 1993;29:438-441.
- Hutson CA , Willauer CC, Walder EJ, et al. Treatment of mandibular squamous cell carcinoma in cats by use of mandibulectomy and radiotherapy: seven cases (1987-1989). J Am Vet Med Assoc 1992;201:777-781.