Equine sarcoids: A clinicopathologic study of 49 cases, with mitotic count and clinical type predictive of recurrence.

Sarcoids are common mesenchymal neoplasms of horses. Although there are few studies in which sarcoids have been followed over a long period of time, sarcoids are considered locally invasive and have been reported to frequently recur following surgical excision. Currently, no histological features have been identified to predict which sarcoids will recur after excision. The present study comprised 49 sarcoids for which histology sections were available and in which the recurrence status of the case was known. Each sarcoid was excised from a different horse. Overall, 12 of the 49 (24%) sarcoids recurred after surgical excision. Mitotic count (MC), cellularity, necrosis, nuclear pleomorphism, and inflammation of the sarcoids were evaluated histologically. Of these, MC correlated with recurrence. Four of 5 (80%) sarcoids with an MC ≥ 20 in 2.37 mm2 recurred, which was a significantly higher recurrence rate than that of sarcoids with an MC < 20, 8 of 44 cases recurred (18%), P = .0051. Clinical type was also found to correlate with recurrence. Three of 4 (75%) fibroblastic types recurred, which was a significantly higher recurrence rate than that of sarcoids with other clinical types, 9 of 45 cases (18%), P < .001. In addition, univariate Cox regression analysis confirmed fibroblastic type and MC ≥ 20 as significant predictors for recurrence (P = .016 and P = .005, respectively). To the authors' knowledge, this is the first large study examining recurrence rates in sarcoids, and the first time that histological features have been correlated with recurrence.

Detection of a novel papillomaviral sequence in viral plaques confined to the pinna of a dog.

A raised plaque that contained histological evidence of papillomavirus infection and sequences from a novel papillomavirus type developed close to the ear canal of a 14-year-old West Highland white terrier. The plaque was excised, and further plaques developed within the same area of pinna.

Une plaque virale à papillomavirus confirmée histologiquement contenant des séquences d'un un nouveau type de papillomavirus se sont développées à proximité du conduit auditif d'un West Highland White âgé de 14 ans. La plaque a été retirée chirurgicalement et d'autres plaques se sont développées dans la même zone du pavillon.

Una placa elevada que contenía evidencia histológica de infección por papilomavirus y secuencias de un nuevo tipo de papilomavirus se desarrolló cerca del canal auditivo de un West Highland White Terrier de 14 años. Se extirpó la placa y se desarrollaron más placas dentro de la misma área del pabellón auricular.

Uma placa elevada apresentando evidências histopatológicas de infecção por papilomavírus e sequências de um novo tipo de papilomavírus surgiu próximo ao conduto auditivo de um West Highland White Terrier de 14 anos de idade. A placa foi removida e outras placas se desenvolveram na mesma área da orelha.

Detection of a Novel Papillomavirus Type within a Feline Cutaneous Basal Cell Carcinoma.

A 4 cm diameter exophytic mass was excised from the left flank of a 10-year-old domestic short-haired cat. Histology of the superficial aspects of the mass revealed epidermal cells arranged in nests and trabeculae while the deeper parts of the mass consisted of small round cells arranged in sheets or bundles of elongate spindle-shaped cells. A diagnosis of basal cell carcinoma (BCC) was made. Approximately 40% of the cells throughout the neoplasm contained prominent papillomaviral (PV)-induced cell changes. The BCC recurred three months after excision and grew rapidly. At this time a smaller mass was observed on the thorax. Due to the rapid recurrence of the BCC, the cat was euthanatized. As in the initial mass, histology of the recurrent mass revealed pleomorphic cells that often contained PV-induced cell changes. In contrast, the thoracic mass appeared as a more typical BCC and contained no histological evidence of PV infection. A novel PV DNA sequence was amplified from the flank BCC. While the sequence was most (75.1%) similar to Felis catus papillomavirus (FcaPV) 6, the level of similarity between the sequences is consistent with a novel PV type. No PV DNA was amplifiable from the thoracic mass. The case is unique due to the histological features of the BCC and the presence of a putative novel PV type. Observations from the present case add to the number of PV types associated with disease in cats as well as increasing the spectrum of PV-induced lesions in this species.

Evidence from a Series of 104 Equine Sarcoids Suggests That Most Sarcoids in New Zealand Are Caused by Bovine Papillomavirus Type 2, although Both BPV1 and BPV2 DNA Are Detectable in around 10% of Sarcoids.

Equine sarcoids are common mesenchymal neoplasms of horses that are caused by cross-species infection by deltapapillomaviruses. While bovine papillomavirus (BPV) 1 and 2 are the most common causes, there are differences between countries regarding which of these BPV types cause the majority of sarcoids. Additionally, no causative PV can be detected in a subset of sarcoids, suggesting that other PV types could be rarer causes of these neoplasms. In the present study, consensus PCR primers and PCR primers specific for the five deltapapillomavirus types currently known to cause mesenchymal neoplasia (BPV1, BPV2, BPV13, BPV14, and Ovis aries PV2 DNA) were used to investigate the presence of PV DNA in 104 sarcoids from three defined regions in New Zealand and from two distinct time periods separated by 15 years. PV DNA was detected in 94 (90.4%) sarcoids. Of the sarcoids containing PV DNA, 83 (88.3%) contained only BPV2 DNA, 9 (9.6%) BPV1 and BPV2 DNA, and 2 (2.1%) only BPV1 DNA. No other PV types were detected. The predominance of BPV2 is consistent with studies of sarcoids from North America but dissimilar to studies of sarcoids from Europe and Australia. Detection rates of BPV1 and BPV2 were similar in sarcoids from different regions of New Zealand and in sarcoids from different time periods. These results suggest that most equine sarcoids in New Zealand are caused by BPV2 and thus if vaccines are developed to prevent sarcoids, vaccines that provide good protection against BPV2 will be required in this country.

Peripheral arteriovenous fistula manifesting as antebrachial dermatopathy in a cat.

CASE DESCRIPTION A 13-year-old neutered male Abyssinian cat with a 4-month history of right forelimb edema and multifocal crusting lesions at the distal aspect of the antebrachium was referred to a veterinary teaching hospital for evaluation. Extensive hemorrhage from the lesions had been observed after self-grooming, and findings on histologic examination of a skin biopsy sample prior to referral were consistent with atypical dermal hemodynamics and inflammation. CLINICAL FINDINGS Diffuse pitting edema and multifocal, 3- to 4-mm-diameter sanguineous crusting lesions affecting the antebrachium were observed distal to a pulsatile subcutaneous mass in the right elbow joint region that had a palpable thrill and auscultable bruit. No systemic abnormalities were detected. TREATMENT AND OUTCOME Contrast-enhanced CT angiography with 3-D reconstruction identified an arteriovenous fistula with a large aberrant vessel coursing distally. Surgical ligation of an arterialized vein distal to the fistula without en bloc resection led to resolution of all clinical signs. The vascular anomaly was no longer patent when diagnostic imaging was repeated 5 months after surgery. CLINICAL RELEVANCE Acquired arteriovenous fistulas can lead to bleeding skin lesions affecting the antebrachium in cats. Surgical ligation of an aberrant reverse-shunting vein distal to the fistula successfully resolved clinical signs in the cat of this report and may warrant investigation as a treatment option in cats with this condition.

Progressive cutaneous viral pigmented plaques in three Hungarian Vizslas and the response of lesions to topical tigilanol tiglate gel.

Cutaneous pigmented viral plaques is a disorder of epidermal growth caused by canine papillomavirus type 4 (CPV-4). There is currently no standard of care for managing this condition and it has not been reported in the Hungarian Vizsla. This case series documents the clinical features of canine pigmented viral plaques in Hungarian Vizsla dogs and the treatment of a severe case using a novel topical agent tigilanol tiglate (EBC-46). A 4-year-old spayed Hungarian Vizsla in Australia was presented for multiple cutaneous pigmented plaques extending from the ventral cervical region. Lesions were neither painful nor pruritic. The number and size of these sessile plaques increased over time, with the largest lesions eventually taking on an exophytic (wart-like) appearance. These lesions did not affect the dog's wellbeing. Two much less severe cases in a 5-year-old Vizsla from the UK and a 7-year-old Vizsla from New Zealand were also diagnosed. Histology was consistent with papillomavirus-induced pigmented plaques and CPV-4 DNA sequences were amplified from paraffin-embedded formalin-fixed tissue using the polymerase chain reaction from the most severely affected patient. Topical imiquimod was ineffective although used for only a short time. Two topical applications of novel anti-neoplastic diterpene ester tigilanol tiglate as a gel, 9 days apart, greatly reduced the size and number of lesions in a limited portion of skin treated, over the lateral hock. While CPV-4 has been previously reported to cause pigmented plaques, most commonly on pug dogs, but sporadically on other breeds, this is the first report of this virus causing plaques in Hungarian Vizslas. The cases illustrate some of the difficulties in diagnosing papillomavirus-induced disease in dogs, especially in its early stages. Topical tigilanol tiglate is a potentially useful topical therapy for this viral-induced disorder of cell growth and represents a treatment deserving of further investigation.

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

Bowenoid in situ carcinomas (BISCs) are papillomavirus (PV)-induced skin neoplasms that are thought to be caused by Felis catus papillomavirus (FcaPV) 2. As BISCs are typically multiple and can become extensive, they can be difficult to treat. Herein we describe 4 cats that developed skin neoplasms that contained FcaPV-3 DNA. One cat developed multiple basal cell carcinomas (BCCs), 1 a BISC with unusual extension into hair follicles, and 2 developed a single typical-appearing BISC. All neoplasms contained prominent PV-induced cell changes and intense p16CDKN2a protein immunostaining. Results from these 4 cats provide evidence that FcaPV-3 could cause a proportion of feline skin cancers, albeit less frequently than FcaPV-2. Excision of the typical BISCs and the BCCs appeared curative. Although the cat with the unusual BISC was euthanized because of the large size of the lesion, evidence from these 4 cats suggests that skin neoplasms that contain FcaPV-3 DNA may have a less aggressive clinical behavior than those associated with FcaPV-2. A consistent feature of the neoplasms in all 4 cats was the presence of prominent basophilic intracytoplasmic inclusion bodies; these inclusions have not been reported in lesions caused by FcaPV-2, to our knowledge, and their detection may allow differentiation between the different PV types and could therefore be a useful prognostic feature.

Bowenoid in situ carcinomas in two Devon Rex cats: evidence of unusually aggressive neoplasm behaviour in this breed and detection of papillomaviral gene expression in primary and metastatic lesions.

BACKGROUND: Bowenoid in situ carcinomas (BISCs) are rare feline tumours that are thought to be caused by papillomavirus infection. Although they usually develop in old cats and are slowly progressive, multiple aggressive BISCs have been reported previously in a comparatively young Devon Rex cat. ANIMALS: A 5-year-old (Case 1) and an 8-year-old (Case 2) Devon Rex cat developed numerous BISCs. Rapid progression resulted in euthanasia of both cats after 8 months. A postmortem examination was possible only for Case 2 and revealed pulmonary metastases. METHODS AND RESULTS: Consensus PCR amplified only Felis catus papillomavirus type 2 (FcaPV-2) DNA from lesions from both cats. High FcaPV-2 copy number and FcaPV-2 E6/E7 gene expression were detected in a BISC from Case 1. High FcaPV-2 copy number and FcaPV-2 gene expression were detected in a BISC, a cutaneous squamous cell carcinoma (SCC) and the pulmonary metastases from Case 2, but not in two other cutaneous SCCs. CONCLUSIONS: The results provide additional evidence that BISCs develop at a younger age in Devon Rex cats and that BISCs in Devon Rex cats have a more aggressive behaviour than BISCs in other cat breeds. These unusual features should be considered when evaluating and treating skin disease in Devon Rex cats. The detection of FcaPV-2 gene expression in the lung neoplasms suggests a potential role of FcaPV-2 in the development of metastatic disease. However, the absence of FcaPV-2 gene expression in two cutaneous SCCs suggests that other factors could have also promoted cancer development.

Meningoencephalitis in an adult cow due to Mortierella woifli.

A 7-year-old dairy cow presented with clinical signs of neurologic disease. Despite treatment with penicillin, the cow died 36 hours after initial presentation. Necropsy examination revealed multiple foci of hemorrhage within the cerebrum and thickened meninges. Additionally, endometritis and consolidation of approximately 30% of both lungs was observed. Histology revealed necrotizing vasculitis, infarction, and hemorrhage within sections of the brain, uterus, and lung. Large numbers of intralesional fungal hyphae were visible. Because only formalin-fixed tissue was available, polymerase chain reaction was used to make an etiologic diagnosis of Mortierella wolfii.