Pedal Papilloma in Dogs
Charlie Pye, DVM, DVSc, DACVD, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
In the literature
Gould AP, Coyner KS, Trimmer AM, Tater K, Rishniw M. Canine pedal papilloma identification and management: a retrospective series of 44 cases. Vet Dermatol. 2021;32(5):509-e141.
The Research …
Papillomavirus infections in dogs have been associated with oral papilloma, venereal papilloma, exophytic cutaneous papilloma, cutaneous inverted papilloma, footpad papilloma, pigmented viral plaque, and development of squamous cell carcinoma.1 Although studies on pedal papilloma have been infrequent, this syndrome appears to be common.
The goal of this study was to report patient signalment, history, treatment, and outcome of biopsy-confirmed pedal papillomatosis cases in North America based on 44 cases submitted by members of an online veterinary community. Median age of dogs was 4 years; 27.3% were <1 year of age. Thirty breeds were represented, with pit bulls, golden retrievers, and Labrador retrievers and their crossbreeds accounting for 36% of cases. The most common clinical signs associated with pedal papilloma were paw licking/chewing and lameness.
Only one paw was affected in 35 dogs; of these, 26 were affected on a thoracic paw. Papillomavirus infection may be associated with trauma,2 possibly leading to thoracic paws being affected more often, as thoracic paws bear more weight compared with pelvic paws and have more contact time with the ground, increasing susceptibility to trauma.3,4
Most dogs (n = 28) had a single papilloma, 2 dogs had 2 papillomas, 5 dogs had 3 to 5 papillomas, and 7 dogs had >5 papillomas. Papillomas typically appeared on haired skin of the paw, but 10 dogs developed papillomas on the paw pads, and 2 dogs developed papillomas on the claw beds. The ventral interdigital region and the underside of a digit were the most common focal locations.
Papillomas resolved in 34 cases (15 with no treatment beyond biopsy collection, 19 with medical therapy), and 25 cases resolved within 3 weeks after biopsy. Recurrence was reported in 5 cases, with recurrence at the same location in 3 cases, at both the same location and distant sites in another case, and at a different site in another case. Same-site recurrence developed within 4 months after excision.
Nearly half of all dogs received no treatment after confirmatory biopsy was collected, and the lesions in most dogs resolved spontaneously. The authors noted it was challenging to determine the efficacy of antiviral treatment, as many papillomas resolved within 3 weeks.
… The Takeaways
Key pearls to put into practice:
Papillomas can resolve quickly with or without medical therapy; however, risk for same-site recurrence should be considered.
Paws should be examined thoroughly for masses in patients presented for lameness and/or paw licking/chewing.
This study did not support a strong association between immunosuppressive medications or comorbidities and development of pedal papillomatosis.