Cutaneous neoplasia

Squamous cell carcinoma (SCC)

• While relatively rare, squamous cell carcinomas may occur via malignant transformation of papillomas caused by the Shope papilloma virus         .
• The Shope papillomavirus (SPV) produces hyperkeratotic nodules, especially on the ears and eyelids. SPV is a naturally occurring pox virus of North and South American wild rabbits ( Sylvilagus spp).
• Infection of domestic rabbits ( Oryctolagus cuniculus ) is rare but has been reported, causing multiple horn-like lesions around the ears and eyelids. Manual removal usually results in healing in wild rabbits.
• In domestic rabbits experimental infection may result in approximately 75% of inoculation sites undergoing malignant transformation to squamous cell carcinoma. Domestic rabbits are occasionally infected via mosquito vectors and develop papillomas which may slough away approximately 30 days post-inoculation, or may transform into SCCs. Newborn and young animals often develop more extensive lesions. Metastasis of the squamous cell carcinomas to the axillary lymph nodes has been reported.
• Experimentally, SCC can be induced in the correct lines by chemical irritation; this suggests that it can be a sequel to chronic irritation, as in other species.
• In pet rabbits, occurrence in poorly furred areas of skin linked to sunlight exposure has also been proposed.
• Diagnosis is based on clinical signs and histopathology.
• Treatment involves removal of the papillomas/SCCs and control of arthropod vectors.

Sources

Publications

Refereed papers

• Recent references from PubMed.
• Sant R & Rowland M (2009) Skin disease in rabbits. In Pract 31 (5), 233-238.
• Jenkins J R (2001) Skin disorders of the rabbit. Vet Clin North Am Exot Anim Pract 4, 543-563 PubMed.
• White S D, Campbell T, Logan A et al (2000) Lymphoma with cutaneous involvement in three domestic rabbits (Oryctolagus cuniculus). Vet Dermatol 11, 61-69.
• White S D, Rosychuk R W, Scott KV et al (1993) Use of isotretinoin and etretinate in the treatment of benign cutaneous neoplasia and cutaneous lymphoma in the dog. JAVMA 202 (3), 387-391 PubMed.

Other sources of information

• Va Praag E, Maurer A & Saarony T (2010) Skin Diseases of Rabbits. Website: www.medirabbit.com.
• White S D, Bourdeau P, Meredith A (2002) Dermatological Problems of Rabbits. Semin Avian and Exotic Pet Med. July.
• Burgmann P (1997) Dermatology of Rabbits, Rodents and Ferrets. In: Practical Exotic Animal Medicine. Ed: Rosenthal K. The Compendium Collection, Trenton, NJ, Veterinary Learning Systems. pp 174-195.