Equus caballus papillomavirus 8 (EcPV8) associated with multiple viral plaques, viral papillomas, and squamous cell carcinoma in a horse

Abstract

Summary Background Equus caballus papillomavirus 8, a recently discovered virus, has been reported to cause generalised papillomavirus in horses. Objectives To describe a case in which multiple viral plaques, viral papillomas, squamous cell carcinoma (SCC) in situ and invasive squamous cell carcinoma (ISCC) were associated with EcPV8 in a horse. Study design Case report. Methods A 16‐year‐old mixed breed horse presented with dozens of raised crusted papular to nodular lesions over a course of 4 years. Masses had been surgically excised four times and cisplatin beads and emulsion were implanted on three different occasions; however new masses continue to develop in sites of previous masses as well as new sites. Results Multiple viral plaques, viral papillomas, SCC in situ and ISCC, localised to the inguinal region, were diagnosed via histopathology. EcPV8 DNA was detected via PCR. Main limitations Since only a few cases have been reported, we do not know the incidence of EcPV8 nor how often it may be associated with SCC in situ or ISCC without further study. Conclusions This is the fourth reported case of viral papillomatosis in the context of an EcPV8 infection in a horse. This is the first case in which SCC has been associated with EcPV8.

Paving the way for more precise diagnosis of EcPV2-associated equine penile lesions

“…Since there are other papillomaviruses described to be associated with equine genital lesions, and co-infections with other PVs were reported [32][33][34], also broad-range PV PCR using CP4/5 [35] and Fap 59/64 [36] primer sets was done to detect other potentially involved PVs. These primers are designed to also detect the equine PVs type 3-8 [32][33][34]37] and the sarcoid associated bovine PVs type 1 and 2 [38]. Using these two broad-range PV primer sets, no other PVs were detectable, hence it is not likely that other PVs were involved in the development of the lesions assessed in this study.…”

Progression of aural plaques to squamous cell carcinoma in a horse

“…Two of the PCRs used degenerate primers for conserved regions to screen for a broad spectrum of PV types with the FAP59/FAP64 assay targeting the L1 gene and the CP4/CP5 assay targeting the E1 gene with HPV6 plasmid DNA as the positive control. 2,12 Nine published EcPV-specific PCRs were used to screen for the DNA of EcPVs 2-7 in the samples, following the published protocols (Table 1). 2,[10][11][12] .…”

“…2,12 Nine published EcPV-specific PCRs were used to screen for the DNA of EcPVs 2-7 in the samples, following the published protocols (Table 1). 2,[10][11][12] . The EcPV-specific PCRs ran without positive controls.…”

“…Of the eight currently identified EcPVs, only EcPV2 and EcPV8 have been associated with SCC, in the genital and inguinal regions, respectively. [8][9][10][11][12] Case report A 28-year-old thoroughbred gelding was presented to Cornell Ruffian Equine Specialists. Surgery was performed to completely excise the right pinna which was partially covered in multifocal to coalescing plaques that transitioned into a large ulcerated painful aural mass (Figure 1).…”

Paving the way for more precise diagnosis of EcPV2-associated equine penile lesions

“…As anticipated on the basis of previous reports reviewed by Sykora et al [4] all lesions tested positive for EcPV2 DNA as revealed by virus type-specific PCR. Since there are other papillomaviruses described to be associated with equine genital lesions, and co-infections with other PVs were reported [32][33][34], also broad-range PV PCR using CP4/5 [35] and Fap 59/64 [36] primer sets was done to detect other potentially involved PVs. These primers are designed to also detect the equine PVs type 3-8 [32][33][34]37] and the sarcoid associated bovine PVs type 1 and 2 [38].…”