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Detection of papillomavirus in equine periocular and penile squamous cell carcinoma
Journal of Veterinary Diagnostic Investigation (2014)
  • K M Newkirk
  • Diane Hendrix, University of Tennessee - Knoxville
  • E A Anis
  • B W Rohrbach
  • E J Ehrhart
  • J A Lyons
  • S A Kania

Squamous cell carcinoma (SCC) is the most common tumor arising in the periocular and penile areas of horses. Both ultraviolet radiation and papillomaviruses have been implicated in the pathogenesis of SCC in various species, including the horse. This retrospective study used polymerase chain reaction (PCR) to detect papillomavirus DNA in archival biopsy samples from equine periocular and penile SCC from 3 different geographic areas (northeast, southeast, and central United States). Forty-two periocular SCCs were tested; none contained papillomavirus DNA. Twenty-two penile SCCs were tested, and papillomavirus DNA was identified in 10 (43%) cases. Sequencing of the PCR products revealed homology with Equus caballus papillomavirus 2 (EcPV-2). No geographic distribution in the detection of papillomavirus was identified. Penile SCCs were significantly more likely to be papillomavirus positive than the periocular SCCs (P < 0.001). The role of papillomavirus in the development of penile SCC requires further investigation. The differing pathogeneses of periocular and penile SCC suggest that the tumors may respond differently to treatment.

Publication Date
January, 2014
Citation Information
K M Newkirk, Diane Hendrix, E A Anis, B W Rohrbach, et al.. "Detection of papillomavirus in equine periocular and penile squamous cell carcinoma" Journal of Veterinary Diagnostic Investigation Vol. 26 Iss. 1 (2014)
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