Felis ISSN 2398-2950

Tonsil: squamous cell carcinoma

Synonym(s): SCC

Contributor(s): Philip K Nicholls, Marion O'Leary

Introduction

  • Oral neoplasms comprise 10% of feline neoplasms.
  • 60-70% of feline oral tumors are squamous cell carcinomas.
  • 10% of feline oral squamous cell carcinomas arise in the tonsil.
  • Typically unilateral.
  • More aggressive biological behavior than other oral squamous cell carcinomas.
  • Signs: hypersalivation, difficulty in swallowing or eating.
  • Diagnosis: signs, biopsy.
  • Prognosis: poor - an aggressive neoplasm with much higher rate of regional lymph node and distant metastasis than other oral squamous cell carcinomas.

Pathogenesis

Predisposing factors

General

  • Risk factors for oral squamous cell carcinoma in general include:
    • Wearing a flea collar (5 x relative risk).
    • Eating a high proportion of canned food (3 x relative risk).
    • Eating tinned tuna.
    • 2-fold (but statistically insignificant) risk associated with exposure to environmental tobacco smoke.
    • Use of flea shampoo was associated with reduced relative risk of oral squamous cell carcinoma in cats.

Pathophysiology

  • Neoplastic transformation of squamous epithelial cell, outgrowth of malignant clones, uncontrolled growth causes mass lesion.
  • Early acquisition of metastatic properties (reduced cell cohesion, ability to invade cell matrix).
  • Early metastasis to regional lymph nodes.
  • Metastasis to remote sites.

Timecourse

  • Rapid progression - often only 2 month survival after diagnosis, even with treatment.

Diagnosis

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Bertone E R, Snyder L A & Moore A S (2003) Environmental and lifestyle risk factors for oral squamous cell carcinoma in domestic cats. J Vet Intern Med 17 (4), 557-562 PubMed.
  • Jones P D, de Lorimer L P, Kitchell B E et al (2003) Gemcitabine as a radiosensitizer for nonresectable feline oral squamous cell carcinoma. J Am Anim Hosp Assoc 39 (5), 463-467 PubMed.
  • Klein M K (2003) Multimodality therapy for head and neck cancer. Vet Clin North Am Small Anim Pract 33 (3), 615-628 PubMed.
  • Herring E S, Smith M M & Robertson J L (2002) Lymph node staging of oral and maxillofacial neoplasms in 31 dogs and cats. J Vet Dent 19 (3), 122-126 PubMed.
  • Rudorf H & Barr F (2002) Echolaryngography in cats. Vet Radiol Ultrasound 43 (4), 353-357 PubMed.
  • Bregazzi V S, LaRue S M, Powers B E et al (2001) Response of feline oral squamous cell carcinoma to palliative radiation therapy. Vet Radiol Ultrasound 42 (1), 77-79 PubMed.
  • Fox L, Rosenthal R C, King R R et al (2000) Use of cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexane platinum (II), a liposomal cisplatin analogue, in cats with oral squamous cell carcinoma. Am J Vet Res 61 (7), 791-795 PubMed.

Other sources of information

  • Harvey C E (1994) Ch 36 Oral and dental diseases. In: Sherding RG (Ed) The Cat - diseases and Clinical Management. pp 1117-1152. Churchill-Livingstone, New York.
  • Couto C G & Hammer A S (1994) Ch 30 Oncology. In: Sherding RG (Ed) The Cat - diseases and Clinical Management. pp 755-818. Churchill-Livingstone, New York.


ADDED