The detection of Felis catus papillomavirus 3 DNA in a feline bowenoid in situ carcinoma with novel histologic features and benign clinical behavior

Abstract

Brief CommunicationPapillomaviruses (PVs) are highly species-specific epitheliotropic DNA viruses. As part of their normal replication, PVs produce oncoproteins that disrupt normal cell regulation. 1 The vast majority of PV infections either do not result in the development of a visible lesion or cause a self-resolving hyperplastic wart. 7 However, the oncogenes produced by a small number of PV types can predispose an infected cell to neoplastic transformation. 1Disease resulting from PV infection is considered uncommon in cats. 8 To date, the disease that is most strongly associated with PV infection in cats is bowenoid in situ carcinoma (BISC; papillomavirus-associated squamous cell carcinoma in situ). 9,13 This neoplasm typically occurs as single or multiple scaly or crusting lesions within haired skin, especially around the head and neck. 4 Cats with BISCs may require euthanasia either because of the development of multiple BISCs or because of progression of a BISC to a squamous cell carcinoma (SCC). Devon Rex, and the closely related Sphinx, cats may be predisposed to BISCs, and BISCs in cats of these breeds are often rapidly progressive. 15A 17-year-old female Domestic Shorthair cat was presented to the primary care veterinarian because of a slightly raised 0.5 cm in diameter interscapular skin mass of uncertain duration.No tests were performed at this time, and a post-injection inflammatory reaction was suspected because the cat had received multiple subcutaneous injections at this location for the management of previously diagnosed diabetes mellitus and chronic renal failure. The mass was reported to have enlarged slowly, and 18 months later had doubled in size to 1 cm in diameter. The cat had no other skin lesions. The mass was surgically removed with 1-cm margins and submitted for histologic examination.On histologic examination, normal epidermis merged abruptly with a well-demarcated focus of marked, irregular epidermal hyperplasia. There were multiple, broad, downward-projecting rete pegs confined by the basement membrane and accompanying mild parakeratosis, hyperkeratosis, and variable melanization. The epidermal hyperplasia also Abstract. Bowenoid in situ carcinoma (BISC; papillomavirus-associated squamous cell carcinoma in situ) is an uncommon skin neoplasm of cats that can result in euthanasia because of the development of multiple lesions or because of progression to invasive squamous cell carcinoma. BISCs are currently thought to be caused by Felis catus papillomavirus 2 (FcaPV-2). The presently described cat developed a single 0.5 cm in diameter interscapular mass. Over the following 18 months, the mass doubled in size; no additional lesions developed. The mass was surgically excised and histologically diagnosed as a BISC. However, in contrast to previously reported BISCs, neither prominent thickening of the deep aspects of the follicular infundibula nor marked cell dysplasia were present. Furthermore, ~50% of the keratinocytes in the affected epidermis had prominent PV cytopathic changes that...

Detection of DNA sequences from a novel papillomavirus in a feline basal cell carcinoma

“…However, the novel PV was most similar to FcaPV‐3 and therefore may be another PV in the Taupapillomavirus genus . The hypothesis that the novel PV and FcaPV‐3 are closely related is supported by the similarity of the basophilic intracytoplasmic bodies within affected cells seen in the present case to those previously reported due to infection by FcaPV‐3, but not FcaPV‐1 or FcaPV‐2 …”

A virome sequencing approach to feline oral squamous cell carcinoma to evaluate viral causative factors

“…FcaPV-3 is not as commonly isolated as FcaPV-2 in cats ( Supplementary Table 1). FcaPV-3 infection has been found in cutaneous SCC, nasal planum SCCs and BISC lesions (Munday et al, 2013a(Munday et al, , 2016Munday et al, 2013b, a;Yamashita-Kawanishi et al, 2018). FcaPV-3 could have been an incidental infection.…”

Identification of Felis catus papillomavirus 3 in skin neoplasms from four cats

“…Such inclusions have been reported previously in a BISC that contained only FcaPV-3 sequences. 11 However, basophilic intracytoplasmic inclusions have not been reported in lesions associated with FcaPV-2. Therefore, histology is likely to enable differentiation between FcaPV-2 and FcaPV-3 and, if prognostic differences between lesions caused by the 2 PV types are proven, these basophilic inclusions could be an easily observed prognostic feature.…”