Breed predilections and prognosis for subungual squamous cell carcinoma in dogs.

Objective: To better document the prevalence, breed predilections, and clinical behavior of subungual squamous cell carcinomas in dogs. Procedure: Retrospective analysis of records from 278 812 canine biopsy submissions including 1518 subungual squamous cell carcinomas from dogs in Canada between the years 2003 and 2021. Results: In agreement with previous studies, giant schnauzers [odds ratio (OR): 56.7], standard schnauzers (OR: 20.3), Gordon setters (OR: 18.3), black standard poodles (OR: 11.1), Kerry blue terriers (OR: 9.4), Rottweilers (OR: 7.0), and several other breeds of large black dogs had a strong predilection for development of subungual squamous cell carcinomas. In giant schnauzers and standard poodles specifically, the risk of developing additional tumors on additional digits was 56%. There were no local postoperative recurrences, and the risk of detecting metastatic disease within 5 y after initial diagnosis was very low at 4%. Conclusion: Moderately large black, or black and tan, dogs have a marked increase in the prevalence of subungual squamous cell carcinomas. At least in giant schnauzers and black standard poodles, the risk of developing additional similar tumors on additional digits is high, but the metastatic risk is very low. Clinical relevance: Veterinarians receiving a histologic diagnosis of subungual squamous cell carcinoma in a large black (or predominantly black) dog should advise the owners of a substantial risk that the dog will develop similar tumors on other digits in 2 or 3 y following initial diagnosis, but that the risk of local recurrence or metastatic spread is extremely low.

Objectif: Mieux documenter la prévalence, les préférences de race et le comportement clinique des carcinomes épidermoïdes sous-unguéaux chez les chiens. Procédure: Analyse rétrospective des dossiers de 278 812 soumissions de biopsies canines, y compris 1518 carcinomes épidermoïdes sous-unguéaux de chiens au Canada entre 2003 et 2021. Résultats: En accord avec les études précédentes, les schnauzers géants [rapport de cotes (OR): 56,7], les schnauzers standards (OR: 20,3), les setters Gordon (OR: 18,3), les caniches standards noirs (OR: 11,1), les Kerry blue terriers (OR: 9,4), Rottweilers (OR: 7,0) et plusieurs autres races de grands chiens noirs avaient une forte prédilection pour le développement de carcinomes épidermoïdes sous-unguéaux. Chez les schnauzers géants et les caniches standards en particulier, le risque de développer des tumeurs supplémentaires sur des doigts additionnels était de 56 %. Il n'y a pas eu de récidive postopératoire locale et le risque de détecter une maladie métastatique dans les 5 ans suivant le diagnostic initial était très faible à 4 %. Conclusion: Les chiens noirs ou noirs et brun-roux de taille moyenne présentent une augmentation marquée de la prévalence des carcinomes épidermoïdes sous-unguéaux. Au moins chez les schnauzers géants et les caniches standards noirs, le risque de développer des tumeurs similaires supplémentaires sur des doigts additionnels est élevé, mais le risque métastatique est très faible. Pertinence clinique: Les vétérinaires qui reçoivent un diagnostic histologique de carcinome épidermoïde sous-unguéal chez un gros chien noir (ou à prédominance noire) doivent informer les propriétaires d'un risque substantiel que le chien développe des tumeurs similaires sur d'autres doigts dans les 2 ou 3 ans suivant le diagnostic initial, mais que le risque de récidive locale ou de propagation métastatique est extrêmement faible.(Traduit par Dr Serge Messier).

Onchocerca lupi Nematodes in Dogs Exported from the United States into Canada.

The Onchocerca lupi nematode is an emerging helminth capable of infecting pets and humans. We detected this parasite in 2 dogs that were imported into Canada from the southwestern United States, a region to which this nematode is endemic. We discuss risk for establishment of O. lupi in Canada.

Feline postvaccinal sarcoma: 20 years later.

Comparison of the annual prevalence of feline postvaccinal sarcomas among 11 609 feline skin mass submissions from 1992 to 2010 revealed no decrease in disease prevalence or increase in the age of affected cats in response to changes in vaccine formulation or recommended changes in feline vaccination protocols.

Bile duct carcinoma and nasal adenocarcinoma in a guinea pig.

A guinea pig with a low grade bile duct carcinoma and nasal papillary adenocarcinoma also had a collagen nevus or lipoma that was considered insignificant in the overall management of the case. The bile duct carcinoma was treated successfully through surgery. The clinical presentation of the adenocarcinoma, which was not treated, is described.

Insulinoma in 2 guinea pigs (Cavia porcellus).

This paper describes an insulinoma in 2 guinea pigs (Cavia porcellus). Both guinea pigs presented with neurologic signs and low blood glucose readings. The neurologic signs resolved with dextrose administration. Insulinoma was confirmed on postmortem examination.

Investigation of repeated vaccination as a possible cause of glomerular disease in mink.

The search for antigens capable of causing immune-complex-mediated glomerulonephritis continues. Modified live-virus vaccines commercially available for veterinary use are a possible source. In this study, repeated vaccination of mink with live-virus vaccines was investigated as a model for vaccine-induced glomerular injury. Three groups of 10-wk-old mink, 15 per group, were vaccinated once with 4-way vaccine against distemper, Pseudomonas aeruginosa infection, botulism and mink viral enteritis. Subsequently, all mink in each group each were vaccinated either with the 4-way vaccine, a monovalent canine distemper vaccine, or saline. Glomerular function was assessed at 2-wk intervals by determining the urinary protein:creatinine (P:C) ratio. Kidney sections taken at necropsy, 20 wk after the 1st vaccination, were examined by light and immunofluorescent microscopy for deposition of immunoglobulin and complement. There was no statistically significant difference between the treated and control groups based on average urinary P:C ratio medians. Light microscopic changes were detected in glomeruli, but Fisher's exact test showed no significant differences between any of the treatment groups. Deposition of immunoglobulin but not complement was significantly more frequent (P < 0.05) in the glomeruli of animals that received multiple injections of the 4-way vaccine than in the glomeruli of those given only the monovalent canine distemper vaccine or saline. These findings suggest that repeated vaccination may increase the glomerular deposition of immunoglobulin. Further studies are required to determine if the increased deposition of immunoglobulin contributes to the development of glomerular damage and to identify the antigens driving production of the deposited immunoglobulin.

A retrospective study of 44 canine apocrine sweat gland adenocarcinomas.

Apocrine sweat gland adenocarcinomas (AACs) are relatively uncommon skin tumors in dogs. Little prognostic or behavioral information has been published for these tumors. In this retrospective study, 44 AACs from diagnostic archives were reexamined and clinical postexcisional follow-ups for 25 of the 44 cases were obtained by a survey. There were 28 out of 44 (65.9%) AACs that invaded the capsule, stroma, or both, 5 of 44 (11.4%) invaded blood vessels and stroma, and 1 out of 25 (4%) had distant metastases. The presence or absence of stromal and vascular invasion was predicted by clinical examination with more than 80% accuracy. Postexcisional median survival of dogs with AACs was 30 mo at the time of survey. Determination of a correlation between histological features and malignant behavior of AACs was compromised by the low number of cases with clinical AAC-related problems; however, it appears that intravascular invasion is an important indicator of potential systemic metastases.

Resurgence of leptospirosis in dogs in Ontario: recent findings.

A marked increase in leptospirosis in dogs was observed in 2000, part of an increasing trend observed in previous years in Ontario. The highest frequency of seropositive cases occurred from September to December 2000, with the peak in November. Large breed dogs were particularly affected. Clinical and clinicopathological data for 31 dogs admitted between 1998 and 2000 to the Ontario Veterinary College Veterinary Teaching Hospital were analyzed. Major clinical presenting features were acute onset of anorexia, depression, fever, and vomiting. Ninety percent of dogs, on admission, showed biochemical evidence of injury to several organs, notably combinations in the order of kidney, muscle, pancreas, and liver. Almost all dogs showed increased serum urea and creatinine levels, and the majority had increased total creatine kinase, bilirubin, alkaline phosphatase, and leukocytosis with neutrophilia. One-third were thrombocytopenic. Of dogs with liver-related abnormalities, most had evidence of cholestasis, with or without hepatocellular damage. Based on serologic studies, in the year 2000, the major serovar involved was autumnalis, but bratislava, grippotyphosa, and pomona were also implicated. The microscopic agglutination test often gave a confusing pattern of reactivities to the serovars that were tested. The high reactivity to serovar autumnalis may represent an erroneous or "paradoxical" reaction typical of early leptospiral serology. The year 2000 was the warmest in Ontario in each of the 4 fall months (September-December) of the previous decade, as well as being the third wettest in the fall period in the last decade. The increase in canine leptospirosis, therefore, may, in part, reflect climate change. The number of positive cases declined in 2001 by about one-third of those in 2000, but the number of submissions of sera for diagnosis increased markedly over previous years. Further work is required to isolate and to identify definitively serovars involved in resurgent canine leptospirosis and the common sources for dogs.

Canine choroidal melanoma with metastases.

A 3-year-old-female, spayed Golden Retriever was examined for a unilateral retinal detachment with exophthalmos. Ultrasonographically, a mass was detected with intra- and extraocular extension. The orbit was exenterated and the dog recovered uneventfully. Histopathologic diagnosis was a primary choroidal melanoma with orbital extension, however, the behavioral and cytologic features were benign. Routine examinations postsurgically were nonremarkable. Twenty-one months after surgery the dog was euthanized for respiratory collapse with radiographic signs of metastasis. Necropsy revealed black lesions in the lung and liver. Histopathologic diagnosis was metastatic melanoma with morphology and behavior identical to the primary choroidal melanoma. This is the first definitive case of a canine choroidal melanoma with metastasis.