Ovarian papillary carcinoma in a Mongolian gerbil (Meriones unguiculatus)

Neoplasms are among the most impacting disease diagnoses in veterinary medicine and have become increasingly common due to the greater longevity of animals as living conditions improved. The Mongolian gerbil is a small rodent species that has become popular recently. In these animals, the occurrence of neoplastic processes is relatively common, mainly tumors of the ventral gland in males and ovarian tumors in females. This work aims to report an ovarian tumor in a Mongolian gerbil Meriones unguiculatus Milne-Edwards 1867 (Rodentia, Muridae). At the initial presentation, the animal had dyspnea, prostration, and increased abdominal volume in the topography of the right ovary of approximately 2 cm. The animal was submitted to exploratory laparotomy because of the emergency nature of the case and the owners' refusal of additional exams due to financial restrictions. Thus, an ovariohysterectomy was performed, followed by a histopathological examination. The histopathology revealed an ovarian papillary carcinoma affecting both ovaries and cystic endometrial hyperplasia. With surgical removal and drainage of the thoracic fluid, the animal showed good recovery, with general improvement and return to regular activity, with a life expectancy of two years. Currently, the demand for specialized veterinarians for unconventional pets is increasing. This condition allows owners to raise their animals more properly, favoring greater longevity. Knowledge about the prevalence and incidence of diseases in different species is of enormous relevance in establishing the appropriate therapy, improving life quality, and increasing life expectancy in animals' lives.(AU)

Cutaneous anaplastic large T-cell lymphoma in a cat: case report / Linfoma cutâneo anaplásico de grandes células T em um gato: relato de caso

Lymphoma is the most common lymphoproliferative disorder in cats. However, cutaneous lymphomas are uncommon in this species and can be classified as epitheliotropic or non-epitheliotropic. Epitheliotropic lymphomas are typically of T-cells and have tropism for epidermis and/or adnexal epithelium. Non-epitheliotropic lymphomas can be of either T-cell or B-cell and involve predominantly the dermis. The present study describes a case of multifocal cutaneous anaplastic large T-cell lymphoma. The skin nodules were multiple and variable in size, alopecic and erythematous in appearance and randomly distributed. Immunohistochemistry revealed positivity for the CD3 antigen, consistent with T-lymphocytes. This neoplasm should be remembered whenever multiple cutaneous nodules are observed in cats.

Linfoma é o distúrbio linfoproliferativo mais comumente observado em gatos. Contudo, linfomas cutâneos são incomuns nessa espécie e podem ser classificados como epiteliotrópico ou não epiteliotrópico. Linfomas epiteliotrópicos são tipicamente originários de células T e têm tropismo pela epiderme e/ou pelo epitélio anexial. Linfomas não epiteliotrópicos podem ser originários de células T ou B e envolvem predominantemente a derme. No presente trabalho, descreve-se um caso de linfoma cutâneo multifocal anaplásico de grandes células T em um gato. Os nódulos cutâneos eram múltiplos, de dimensões variáveis, alopécicos, eritematosos e aleatoriamente distribuídos. A imuno-histoquímica revelou positividade para CD3, sendo consistente com origem em linfócitos T. Essa neoplasia deve ser lembrada sempre que forem observados nódulos cutâneos múltiplos em gatos.

Carcinoma de células escamosas (cce) em cão na região prepucial: relato de caso / Squamous cell carcinoma (scc) in dog in the preputial region: case report / Carcinoma de células escamosas (cce) en perro de la región prepucial: reporte de un caso

A expectativa de vida dos animais de companhia vem aumentando devido as mudanças comportamentais e de cuidados dos tutores. Em analogia, com as idades cada vez mais avançadas, é comum o desenvolvimento de doenças associadas, sendo o tumor o mais comum entre elas. Todavia, as neoplasias mais comuns na clínica de pequenos animais estão associadas ao sistema tegumentar. O carcinoma de células escamosas (CCE), ou carcinoma espinocelular, é uma neoplasia de epitélio, maligno, de crescimento lento e de baixo potencial metastático. Sua etiologia ainda não é precisamente conhecida e a causa exógena mais comum e descrita pela literatura é a exposição à luz ultravioleta, gerando consequentes lesões nas estruturas genéticas e imunogênicas na pele. Além disso, essas lesões apresentam-se de forma mais comum em animais de pelagem clara, com grande exposição solar e em área anatômicas hipopigmentadas. O prognóstico varia de acordo com a localização e o estágio clínico, sendo favorável o diagnóstico realizado precocemente, e o tratamento consiste na avaliação clínica seguida do protocolo adequado O presente relato de caso tem como objetivo principal reunir e discutir informações associadas sobre o carcinoma de células escamosas em caninos e felinos, abordando aspectos clínicos e patológicos, a fim de facilitar o raciocínio sobre o CCE, desde sua abordagem inicial, até seu diagnóstico final e estadiamento.(AU)

The life expectancy of companion animals has been increasing due to behavioral and care changes of the guardians. In analogy, with the increasingly advanced ages, the development of associated diseases is common, the tumor being the most common among them. However, the most common neoplasms in the small animal clinic are associated with the integumentary system. Squamous cell carcinoma (SCC), or squamous cell carcinoma, is a malignant, slow-growing, low-potential metastatic epithelial neoplasm. Its etiology is not yet precisely known and the most common exogenous cause described by the literature is exposure to ultraviolet light, generating consequent lesions on the genetic and immunogenic structures in the skin. In addition, these lesions are more common in light-haired animals, with high exposure to the sun, and in hypopigmented anatomical areas. The prognosis varies according to the location and clinical stage, being favorable to the early diagnosis, and the treatment consists in the clinical evaluation followed by the appropriate protocol. The present case report has as its main objective to gather and discuss associated information about squamous cell carcinoma in canines and cats, addressing clinical and pathological aspects, in order to facilitate the reasoning about the CCE, from its initial approach, to its final diagnosis and staging.(AU)

La esperanza de vida de los animales de compañía ha ido en aumento debido a los cambios de comportamiento y cuidado de los guardianes. Por analogía, con las edades cada vez más avanzadas, el desarrollo de enfermedades asociadas es común, siendo el tumor el más común entre ellos. Sin embargo, las neoplasias más comunes en la clínica de animales pequeños se asocian con el sistema tegumentario. El carcinoma epidermoide (CCE), o carcinoma epidermoide, es una neoplasia epitelial metastásica maligna de crecimiento lento y bajo potencial. Su etiología aún no se conoce con precisión y la causa exógena más común descrita por la literatura es la exposición a la luz ultravioleta, generando lesiones consecuentes en las estructuras genéticas e inmunogénicas de la piel. Además, estas lesiones son más comunes en animales de pelo claro, con alta exposición al sol, y en áreas anatómicas hipopigmentadas. El pronóstico varía según la localización y el estadio clínico, siendo favorable al diagnóstico precoz, y el tratamiento consiste en la evaluación clínica seguida del protocolo adecuado. El presente reporte de caso tiene como objetivo principal reunir y discutir información asociada sobre el carcinoma epidermoide en caninos y gatos, abordando aspectos clínicos y patológicos, con el fin de facilitar el razonamiento sobre el CCE, desde su abordaje inicial, hasta su diagnóstico final y estadificación.(AU)

Lomustine for treatment of canine transmissible venereal tumor / Eficácia da lomustina no tratamento do tumor venéreo transmissível canino

Canine transmissible venereal tumor (TVTC) is a highly casuistic transmissible neoplasm in Brazil. Chemotherapy with vincristine sulfate is considered the treatment of choice, but the need for weekly applications and hematological monitoring, in addition to costs, are obstacles to owners' adhesion to the treatment. Lomustine is an alkylating class antineoplastic agent, and because it is administered orally, it is a more practical and less costly treatment option for the owners of animals with neoplasms sensitive to the drug. This study evaluated the therapeutic efficacy of lomustine in dogs affected by TVTC. Twelve dogs with cytopathological diagnosis of natural genital TVTC were selected. The dogs were submitted to the experimental protocol with lomustine administration at doses of 70 to 85 mg/m2 orally every 21 days, totaling a maximum of two administration cycles. The animals were reevaluated every 7 days until a maximum of +49 days after the first dose of lomustine, to monitor the regression of neoplastic lesions through measurements. Among the 12 dogs submitted to the lomustine protocol, 8/12 achieved complete remission of the neoplasm and were considered cured (66.6%), 1/12 had partial response to treatment (8.33%) and 3/12 had stable disease (25%). Important adverse effects such as severe neutrophilic leukopenia were detected in 3/12 dogs (25%). The clinical study indicated that lomustine may be a treatment option for TVTC.

O tumor venéreo transmissível canino (TVTC) é uma neoplasia transmissível de elevada casuística no Brasil. A quimioterapia com sulfato de vincristina é considerada o tratamento de escolha, mas a necessidade de aplicações semanais e acompanhamento hematológico, além dos custos, são obstáculos à adesão dos proprietários ao tratamento. A lomustina é um antineoplásico da classe dos agentes alquilantes e, por ser administrado por via oral, representa um opção de tratamento mais prática e menos onerosa para os proprietários de animais com neoplasias. O objetivo deste estudo foi avaliar a eficácia terapêutica da lomustina em cães acometidos por TVTC. Foram selecionados 12 cães com diagnóstico citopatológico de TVTC genital de ocorrência natural. Os cães foram submetidos ao protocolo experimental com administração de lomustina nas doses de 70 a 85 mg/m2 por via oral a cada 21 dias, totalizando no máximo dois ciclos de administração. Os animais foram reavaliados a cada sete dias até um máximo de +49 dias após a primeira dose de lomustina, para monitorar a regressão das lesões neoplásicas por meio de mensuração das lesões. Entre os 12 cães submetidos ao protocolo, 8/12 obtiveram remissão completa da neoplasia e foram considerados curados (66,6%), 1/12 tiveram resposta parcial ao tratamento (8,33%) e 3/12 tiveram doença estável (25%). Efeitos adversos importantes, como leucopenia neutrofílica grave, foram detectados em 3/12 cães (25%). O estudo clínico indicou que a lomustina pode ser uma opção de tratamento para TVTC.

Cutaneous apocrine adenocarcinoma in a goat

Apocrine neoplasms are rare in goats. This report describes an apocrine adenocarcinoma in a 5-year-old female Boer goat with an ulcerated, exophytic, multilobulated mass on the left dorsolateral cervical area. Histologically, the dermis was effaced and expanded by a poorly demarcated epithelial neoplasm with desmoplasia. Neoplastic cells were arranged in acini with papillary projections into the lumen and had cuboidal or columnar, eosinophilic, occasionally vacuolated cytoplasm. Nuclei were round and had finely stippled chromatin with one nucleolus. Neoplastic cells contained periodic acid-Schiff (PAS)­positive and diastase­resistant, alcian blue­positive cytoplasmic granules. There were 6 mitoses in 2.37 mm2 (equivalent to 10 FN22/40X fields). Histologic and histochemical features in the current case were consistent with a cutaneous apocrine gland adenocarcinoma.(AU)

Clinical presentation, histological findings, and prognosis in female dogs with mixed mammary neoplasms / Apresentação clínica, achados histológicos e prognóstico em cadelas com neoplasias mamárias mistas

The aim of this study was to describe the clinical and morphological characteristics of mixed mammary neoplasms and verify what characteristics affect the prognosis of female dogs with carcinomas in mixed tumors and carcinosarcomas. This was a retrospective study of 67 female dogs that underwent mastectomies and were diagnosed with benign mixed tumors (n=13), carcinomas in mixed tumors (n=44) and carcinosarcomas (n=10). Data regarding the clinical and histological aspects of the neoplasms were collected and the relation with specific survival times, and hazard ratios (HR) in 24 months was calculated. In univariate analysis, the diagnosis of carcinosarcoma (HR 8.26, p=0.006), carcinomatous areas with micropapillary or solid patterns (HR 17.49; p=0. 001) and lymph node metastasis (HR 7.07;p=0.020) were associated with specific survival. In multivariable analysis, only micropapillary or solid pattern (HR=16.34; p=0.007) remained independent factor associated with lower specific survival. Micropapillary or solid carcinomatous patterns were associated with shorter specific survival time (p=0.002) among animals with carcinomas in mixed tumors. Among the carcinosarcomas, lymph node metastasis (p=0.010) was associated with a shorter specific survival time. In conclusion, carcinomas in mixed tumors and carcinosarcomas vary in prognosis depending on the carcinomatous proliferation patterns and spread of the disease.

O objetivo deste estudo foi descrever as características clínicas e morfológicas das neoplasias mamárias mistas e verificar quais características interferem no prognóstico de cadelas com carcinomas em tumores mistos e carcinossarcomas. Este foi um estudo retrospectivo de 67 cadelas, que foram submetidas a mastectomias e diagnosticadas com tumores mistos benignos (n = 13), carcinomas em tumores mistos (n = 44) e carcinossarcomas (n = 10). Foram coletados dados sobre os aspectos clínicos e histológicos das neoplasias e a relação com o tempo de sobrevida específica e a razão de risco (OR) em 24 meses foram calculadas. Na análise univariada, o diagnóstico de carcinossarcoma (HR 8,26; p=0,006), as áreas carcinomatosas com padrão micropapilar e sólido (HR 17,49; p= 0,001) e metástase linfonodal (HR 7,07; p=0,020) foram associadas à menor sobrevida específica. Na análise multivariável, apenas o padrão micropapilar ou sólido (HR=16,34; p=0,007) permaneceu como fator independente associado à sobrevida. Proliferações carcinomatosas micropapilares ou sólidas (p = 0,002) foram associadas a tempos de sobrevida específica mais curtos entre os animais com carcinomas em tumor misto. Entre os pacientes com carcinossarcoma, metástases em linfonodos (p = 0,010) foram associadas a um menor tempo de sobrevida específica. Em conclusão, os resultados mostraram que os carcinomas em tumores mistos e os carcinossarcomas podem ter prognóstico variável, dependendo do padrão de proliferação carcinomatosa e da disseminação linfática da doença.

Lesions of the oral cavity of dogs: 720 cases / Lesões da cavidade oral de cães: 720 casos

Seven hundred twenty cases of oral cavity lesions in dogs were diagnosed from 2015 to 2020 in Distrito Federal, Brazil. Four hundred thirty-two (60%) lesions were neoplastic, and 288 (40%) were non-neoplastic. Of the neoplasms, 229 (53%) were considered malignant and 203 (47%) benign, affecting mainly males, of 43 different breeds, with an average age of 9.4 years, mainly the gum and lip. Melanoma was the most (96/432, 22.2%) commonly diagnosed neoplasm, followed by peripheral odontogenic fibroma (68/432, 15.7%), papilloma (63/432, 14.5%) and squamous cell carcinoma (SCC) (56/432, 12.9%). Non-neoplastic lesions also affected males predominantly, from 41 different breeds, with an average age of 8.9 years, mainly in the gums, lip, and tongue. These lesions were diagnosed as inflammatory (230/288, 79.8%), hyperplastic (47/288, 16.3%) and other lesions (11/288, 3.8%).

Foram estudados 720 casos de lesões na cavidade oral em cães diagnosticados entre 2015 e 2020, no Distrito Federal. Dessas alterações, 432 (60%) foram neoplásicas e 288 (40%) não neoplásicas. Dentre os neoplasmas, 229 (53%) foram consideradas malignos e 203 (47%) benignos, acometendo principalmente machos, de 43 raças diferentes, com idade média 9,4 anos, afetando principalmente gengiva e lábio. Melanoma foi o neoplasma mais comumente diagnosticado (96/432; 22,2%), seguido do fibroma odontogênico periférico (68/432; 15,7%), papiloma (63/432; 14,5%) e carcinoma de células escamosas (56/432; 12,9%). As lesões não neoplásicas também acometeram predominantemente machos, de 41 raças diferentes, com idade média 8,9 anos, afetando principalmente gengiva, lábio e língua. Essas lesões foram diagnosticadas como inflamatórias (230/288; 79,8%), hiperplásicas (47/288; 16,3%) e como outras alterações (11/288; 3,8%).

Fibroblastic osteosarcoma in a guinea pig (Cavia porcellus)

The article describes the case of a 3 year 6 months old Guinea Pig (Cavia porcellus) that was assisted at the Wildlife and Exotic Animal Practice of the Faculty of Veterinary Sciences, National University of Asunción. The patient presented a hard mass in the right hind limb extending from the proximal portion of the femur, projecting caudally to the proximal tuberosity of the calcaneus, with an increase in temperature, and a marked increase in sensitivity. Radiographic diagnosis refers to a mass with amorphous areas of mineral density. Fine needle aspiration puncture revealed an undifferentiated malignant proliferative process, requiring histopathological analysis to characterize the process. Disarticulation was performed and subsequent histopathologic diagnosis under hematoxylin-eosin and Masson's trichrome stain revealed fibroblastic osteosarcoma.(AU)

Primary hypothyroidism due to thyroid carcinoma in a feline / Hipotireoidismo primário devido a carcinoma de tireóide em um felino

Hypothyroidism is rarely observed in cats. This article reports the case of a thirteen-year-old feline with a one-year history of bilateral cervical swelling that had majorly grown in size two weeks prior to the animal's admission. The cat presented with dysphonia, lethargy, weight gain, and constipation. On physical examination, hypothermia was observed, with a rectal temperature of 36.5 ºC. Fine-needle aspiration cytology suggested thyroid neoplasia. The serum levels of total T4 and thyroid stimulating hormone (TSH), along with the exclusion of non-thyroid diseases, confirmed the diagnosis of hypothyroidism. This is the first report of feline hypothyroidism in Brazil secondary to thyroid neoplasia, classified as a follicular-compact carcinoma and confirmed by histopathology.

Hipotireoidismo é uma doença rara na espécie felina. Esse trabalho relata um felino de treze anos de idade com histórico de inchaço cervical bilateral há um ano, que havia crescido principalmente duas semanas antes da admissão do animal. O felino apresentava disfonia, letargia, ganho de peso e constipação. No exame físico, hipotermia foi observado com temperatura retal de 36,5 ºC. Citologia aspirativa de agulha fina sugeriu neoplasia de tireoide. A dosagem sérica de T4 total e TSH junto com a exclusão de doenças não tireoidianas confirmaram o diagnóstico de hipotireoidismo. Esse é o primeiro relato de hipotireoidismo felino no Brasil devido a uma neoplasia de tireoide, classificado como carcinoma folicular-compacto, confirmado na histopatologia.

Carcinoma de tireoide associado à metástase pulmonar e efusão pleural em um gato: relato de caso / Thyroid carcinoma associated with pulmonary metastasis and pleural effusion in a cat: case report

O presente trabalho relata um caso de carcinoma de tireoide em um felino doméstico, SRD de 10 anos de idade, fêmea, em que foram realizados exames laboratoriais e de imagem no laboratório veterinário Delort em Jundiaí (SP). A paciente apresentava apenas perda de peso e aumento de volume em região cervical ventral no início do quadro. Durante os exames de ultrassom abdominal e radiografia torácica observou-se presença de efusão pleural e opacificação pulmonar por padrão miliar, o que sugeria um quadro metastático. Após os achados o paciente foi encaminhado para o oncologista, além de ser realizada a colheita de material para exame citológico, onde foi confirmado o diagnóstico de carcinoma.(AU)

This paper reports a case of thyroid carcinoma in a crossbreed domestic feline, 10 years old, female. Laboratory and imaging exams were performed at the veterinary laboratory Delort in Jundiaí (SP). The patient presented weight loss and volume increase in the ventral cervical region at the beginning of the condition. During abdominal ultrasound and thorax radiography, pleural effusion and pulmonary opacification by miliary pattern were observed, which suggested a pulmonary metastasis. After the findings, the patient was referred to the oncologist, in addition to the collection of material for cytological examination, where the diagnosis of carcinoma was confirmed.(AU)

Hiperplasia fibroepitelial mamária em um gato macho: relato de caso / Mammary fibroepithelial hyperplasia in a male cat: case report

As neoplasias mamárias representam a terceira neoplasia mais comum em gatas, enquanto nos machos a incidência é rara. Esse trabalho relata o caso de um gato macho, não castrado, atendido no Hospital Veterinário da Universidade Estadual do Ceará, com uma neoformação mamária. O diagnóstico inicial, obtido por meio de punção aspirativa por agulha fina, sugeriu a presença de carcinoma mamário. Exames de imagem como a radiografia torácica e a ultrassonografia abdominal não evidenciaram a presença de metástase no parênquima pulmonar e nos órgãos abdominais, respectivamente. O tratamento instituído foi a remoção cirúrgica da neoformação, pela técnica de mastectomia parcial bilateral. O exame histopatológico da massa evidenciou uma hiperplasia fibroepitelial. Diante disso, conclui-se que, apesar de raras, as neoformações mamárias em gatos do sexo masculino podem ocorrer, devendo, dessa forma, compor parte da lista de diagnósticos diferenciais para aumentos de volume na região ventral desses animais.(AU)

Mammary neoplasms represent the third most common neoplasm in queens, while in tomcats the incidence is rare. This study reports the case of a tomcat, not neutered, treated at the Veterinary Hospital of the State University of Ceará, with a mammary neoformation. The initial diagnosis, obtained through aspiration cytology, suggested the presence of mammary carcinoma. Imaging tests such as thoracic radiography and abdominal ultrasound, did not show the presence of metastasis in the lung parenchyma and abdominal organs, respectively. The chosen treatment was the surgical removal of the neoformation, using the bilateral partial mastectomy technique. Histopathological examination of the mass showed a mammary fibroepithelial hyperplasia. Therefore, it is concluded that, although rare, mammary neoformations in male cats can occur, thus, it should be part of the list of differential diagnoses for increases in volume in the ventral region of these animals.(AU)

Adenocarcinoma pancreático em um gato / Pancreatic adenocarcinoma in a cat

Background: Despite being rare in domestic animals, pancreatic adenocarcinoma is the most common malignant tumor of the feline pancreas. Due non-specificity of clinical signs in cats and the late diagnosis of the neoplasm, it is necessary to understand this disease better, to contribute for the knowledge of its early recognition and treatment. Thus, this study aims to report a case of metastatic pancreatic ductal adenocarcinoma in a cat, focusing on the main clinical aspects, diagnosis, and prognosis of this disease, in addition to the description of the presentation of peritoneal carcinomatosis. Case: A 14-year-old male neutered mixed breed cat, was referred to the Feline Medicine Service (MedFel) of the Hospital de Clínicas Veterinárias (HCV) - Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, with a history of hyporexia, constipation and increased abdominal volume for 3 days, besides mild difficulty in locomotion and progressive weight loss in the last 6 months. On the physical examination, the patient was alert, with a body condition score of 6/9; muscle condition score 1/4 and moderate dehydration of 7%. Popliteal lymph nodes were enlarged, and abdominal distension was evident. Around 200 mL of a slightly cloudy, straw-yellow liquid were drained from the abdominal cavity. After draining the fluid, a new abdominal palpation was performed, and there were fecal retention and a palpable mass in the right hypogastric region. The result of the cytological analysis of the fluid was consistent with a protein-rich transudate, suggesting neoplastic effusion of epithelial origin. Hematological and biochemical changes included leukocytosis due to neutrophilia, monocytosis, lymphopenia, thrombocytosis and azotemia. On abdominal ultrasound, the patient had free fluid in the abdominal cavity, and the gallbladder had discreet of biliary sludge. The intestines showed some corrugated segments with other segments lacking definition of its layers, and without peristaltic movements, suggesting intestinal neoplasia. Pancreas and adrenals were not visualized. On the chest X-ray, moderate opacification of lung fields with a diffuse interstitial pattern was observed, suggesting lung metastasis. The patient presented an acute worsening of the clinical condition and the owner requested euthanasia. The patient was referred for necropsy and based on the macroscopic and microscopic changes, the post-mortem diagnosis was metastatic pancreatic ductal adenocarcinoma with peritoneal carcinomatosis. Discussion: The clinical presentation of cats with exocrine pancreatic neoplasia is nonspecific, as clinical signs are common to several diseases, such as anorexia, vomiting, abdominal pain, weight loss with normal appetite, jaundice, depression, and lethargy. Complementary blood tests also do not provide data that could lead to the suspicion of pancreatic neoplastic disease. In the present case, the diagnosis of metastatic pancreatic ductal adenocarcinoma with peritoneal carcinomatosis was only possible post mortem. The pancreas is a difficult organ to assess adequately using most diagnostic imaging methods, so histopathology is still the method of choice for differentiating pancreatic tissue comorbidities. Therefore, exploratory laparotomy should be instituted to provide tissue samples from the pancreas and its metastases for histopathological diagnosis, whenever ultrasound or other imaging methods indicate suspicious abdominal changes. The literature reports that less than 10% of affected cats treated with complete surgical removal of the mass and chemotherapy alone will survive more than a year, and the average time for untreated cats is only 6 days. The prognosis of this disease is bad and most cats are euthanized, due to rapid clinical worsening. Therefore, diagnosis is essential to determine an adequate prognosis in advanced cases and to support therapeutic decisions or euthanasia.

Retrospective evaluation of canine anal sac carcinoma (260 cases) in Brazil: late detection and failures in lymph node evaluation / Avaliação retrospectiva do carcinoma de saco anal canino (260 casos) no Brasil: detecção tardia e falhas na avaliação dos linfonodos

Anal sac neoplasms are common in companion animals, and the epidemiological profile has been extensively described in international studies; however, national data are still lacking. Data on the Brazilian reality of anal sac carcinoma cases' diagnosis and treatment are also scarce. The purpose of this study was to retrospectively evaluate cases of canine anal sac carcinoma and assess the profile of involvement, tumor size, and lymphatic invasion at the time of diagnosis. Information was obtained from Vetpat laboratory database, from 260 cases spanning a 12-year period (2010-2021). In histopathological evaluation at the time of diagnosis, data on sex, age, and race were described, as well as tumor size and lymphatic invasion. The presence of metastasis was also assessed in cases where lymph nodes were sampled. Simple descriptive statistical analysis was used to evaluate the data. Adult and elderly, female, and mixed-breed animals were more involved, indicating differences from international studies that can be attributed to sociocultural factors. In terms of tumor size, it was observed that 93% of the cases had the largest diameter above 2.5cm. Only 7% of the cases had the largest diameter below 2.5cm, demonstrating the often late diagnosis and the importance of rectal palpation examination during the general physical assessment of canine patients, particularly at an advanced age. Regarding lymphatic invasion and affected lymph nodes, 50% of the cases had lymphatic invasion described in the histopathological examination. However, only 5% of the lymph nodes were sent along with the primary tumor, indicating the disease's aggressive behavior but with possible metastases underdiagnosed.

As neoplasias de saco anal possuem incidência importante nos animais de companhia, tendo o seu perfil epidemiológico de acometimento amplamente descrito em estudos internacionais, entretanto dados nacionais ainda são escassos. De modo semelhante, dados acerca da realidade brasileira, associados ao diagnóstico e conduta desses casos, são inexistentes. O objetivo do presente trabalho foi avaliar, de forma retrospectiva, os casos de carcinoma de saco anal canino, avaliando o perfil de acometimento, o tamanho tumoral e a invasão linfática no momento do diagnóstico. Foi obtido informações de 260 casos, respectivo a um período de 12 anos (2010-2021), proveniente do banco de dados do laboratório Vetpat. Foram descritos os dados acerca do sexo, idade e raça, bem como o tamanho tumoral e presença de invasão linfática em avaliação histopatológica no momento do diagnóstico. Os casos que cursavam com envio dos linfonodos também foram avaliados quanto a presença de metástase. Os dados foram avaliados mediante análise estatística descritiva simples. Foi encontrado um maior acometimento em animais adultos a idosos, do sexo feminino e sem raça definida, evidenciando diferenças em relação a estudos internacionais, que podem ser atribuídas a fatores socioculturais. Em relação ao tamanho tumoral, observou-se que 93% dos casos apresentavam o maior diâmetro acima de 2,5cm e apenas 7% dos casos apresentavam o maior diâmetro abaixo de 2,5cm, evidenciando o diagnostico frequentemente tardio, bem como a importância do exame de palpação retal durante a avaliação física geral de pacientes caninos, principalmente em idade avançada. Quanto a avaliação da invasão linfática e linfonodos acometidos, 50% dos casos cursavam com invasão linfática descrita em exame histopatológico, entretanto em apenas 5% dos casos os linfonodos foram enviados junto ao tumor primário, evidenciando o comportamento agressivo da doença, porém com metástases possivelmente subdiagnosticadas.

Mastocitoma cutâneo canino após mastocitose acidental induzida por opioide: Relato de caso / Canine cutaneous mastocytoma after accidental opioid-induced mastocytosis: Case report

A aproximação entre petse tutores está cada vez mais presente na rotina atual das residências familiares. Essa aproximação aumenta a observação de quaisquer alterações físicas ou comportamentais dos animais levando-o a buscar um médico veterinário quando necessário. O papel do clínico, oncologista e do patologista veterinário vem a ser de extrema importância para detecção das neoplasias em suas fases iniciais. A utilização dos meios de diagnósticos complementares para os casos de neoplasias é de fundamental importância para ter ciência do prognóstico do animal e de qual tratamento será o melhor tratamento para os casos abordados. O mastocitoma é a neoplasia cutânea mais frequente do cão, é uma neoplasia maligna e sua etiologia é pouco compreendida. Independente do sexo, atingem machos e fêmeas, porém se apresentam de forma mais agressiva em machos. O diagnóstico, geralmente é estabelecido por meio de exames complementares, associados aos sinaisclínicos, devendo sempre prezar pelo diagnóstico precoce para que haja maior êxito no tratamento.O exame citológico para o diagnóstico de mastocitoma é um dos métodos mais eficientes e de baixo custo, sendo complementado pelo exame histopatológico para agraduação de malignidade e estadiamento da doença. Preconiza-se a associação da cirurgia com o tratamento quimioterápico com terapia antiblástica e eletroquimioterapia para um melhor prognóstico. O objetivo deste trabalho foi relatar um caso de mastocitoma cutâneo após um erro primário de manejo clinico, em um canino, macho, nove anos, da raça American Pitbull Terrier, trazendo sua complexidade e bases dos meios de diagnóstico(AU)

The approximation between pets and tutors is increasingly present in the current routine of family homes. This approach increases the observation of physical or behavioral changes in animals, leading them to seek a veterinarian when necessary. The role of the clinician, oncologist and veterinary pathologist is extremely important for the detection of neoplasms in their early stages. The use of complementary diagnostic means for cases of neoplasms is of fundamental importance to be aware of the animal's prognosis and which treatment will be the best treatment for the cases examined. Mastocytoma is the most frequent skin neoplasm in dogs, it is a malignant neoplasm and its etiology is poorly understood. Regardless of gender, they affect males and females, but are more aggressive in males. The diagnosis is usually established through complementary exams, associated with clinical signs. Cytological examination for the diagnosis of mast cell tumor is an inexpensive method and one of the most efficient methods, being complemented by histopathological examination for its evolution of malignancy and disease staging, recommended the association of surgery with chemotherapy treatment with antiblastic therapy and electrochemotherapy for better prognoses. The aim of this study was to report a case of cutaneous mastocytoma after a primary error in clinical management, in a canine, male, nine years old, of the American Pitbull Terrier breed, bringing its complexity and bases of the means of diagnosis(AU)

Primary pulmonary chondrosarcoma in a bitch

Background: Primary lung neoplasms are uncommon in veterinary medicine, and when they develop, they are more frequently observed to be of epithelial origin. Although chondrosarcomas are the second most diagnosed type of neoplasm in dogs at skeletal sites, their development in extraskeletal tissues, including the spleen, aorta, heart, tongue, peritoneum, and lungs, corresponds to approximately only 1% of cases. Therefore, the occurrence of primary pulmonary chondrosarcoma is considered very rare in domestic animals. Considering the rare occurrence and scarcity of data regarding its development, the present report describes the clinical and pathological aspects of a case of primary pulmonary chondrosarcoma in a bitch. Case: A 8-year-old mixed-breed bitch, weighing 14.2 kg, was examined at one private veterinary clinic with the principal complaint of prolonged respiratory distress and resistance to exercise. Clinical evaluation revealed tachypnea with expiratory dyspnea due to intense pleural effusion, tachycardia, and diffusely pale mucous membranes. Thoracocentesis was performed with drainage of 1000 mL of modified transudate, and fluid cytology, blood count, and chest radiography were performed. Cytological analysis of the thoracic fluid did not identify neoplastic cells, the blood count showed intense regenerative anemia, and the radiograph showed an extensive area of consolidation in the left caudal lung lobe, compatible with neoplasia. The results of the tests performed, in addition to the evolution of the clinical picture and the impossibility of performing the indicated surgical intervention, culminated in the patient's unfavorable prognosis, followed by euthanasia, necropsy, and histopathological evaluation of the collected material. Necropsy revealed a white neoplastic formation with reddish areas and firm consistency that diffused into the parenchyma of the left caudal lung lobe with invasion of the rib cage, fracture of the fifth and sixth left ribs, diaphragmatic metastasis, intense hydrothorax, and moderate hydroperitoneum. Microscopically, in the histological sections of the lung and diaphragm, poorly differentiated mesenchymal cells with moderate anisocytosis and anisokaryosis and interspersed with them, moderately differentiated chondrocytes surrounded by chondroid matrix, moderate anisocytosis and anisokaryosis, and a low mitotic index culminated in the diagnosis of primary pulmonary mesenchymal chondrosarcoma. Discussion: Malignant epithelial neoplasms were suspected; however, the histopathological features observed were compatible with primary pulmonary chondrosarcoma. The characteristics of the fluid collected through thoracentesis led to its classification as a modified transudate, which is often associated with neoplastic and hemorrhagic processes; both alterations were present in this case. The diagnosis of primary pulmonary chondrosarcoma was established based on the histopathological findings since the cell type and distribution observed in the present case were compatible with the typical pattern observed in extraskeletal chondrosarcomas. An unfavorable prognosis is common in cases of primary or metastatic lung neoplasm since, in most cases, the condition is identified in the advanced stages of the disease, making therapeutic management challenging. Given the increase in the number of dog deaths due to neoplasms in recent years, this case report may contribute to a better understanding of the biological behavior of pulmonary chondrosarcoma and assist in the choice of treatment to be adopted when required.

Adenocarcinoma de saco anal com metástase vertebro-medular em um Cocker Spaniel / Anal sac adenocarcinoma with vertebromedullary metastasis in a Cocker Spaniel

Background: Several neoplasms can affect the perianal region, being the hepatic adenoma and the anal sac adenocarcinoma (ASAC), which is considered the most frequent. The ASAC is a malignant neoplasm originating from the secretory epithelium of the perianal apocrine glands and is rarely seen in veterinary medicine. The ASAC occurs mainly in adult to elderly canines with high metastasis rates. Patients may be asymptomatic or manifest discomfort and behavioral changes. In the presence of metastasis, the most frequent clinical signs are inappetence, coughing, dyspnea, and colorectal obstruction. Given this scenario, this paper aims to describe the clinical presentation, diagnostic examination, and necropsy findings of a Cocker Spaniel with ASAC and metastasis in the vertebral body, spinal cord, and cauda equina. Case: A 8-year-old neutered male Cocker Spaniel (12 kg of body mass) with a clinical history of non-ambulatory paraparesis was evaluated. The patient also presented tenesmus, difficulty to defecate, and the presence of nodules in the anal sac area. On the neurological examination, asymmetrical changes compatible with injury between L4-S3 were found. A complete blood count, serum biochemistry, and imaging exams such as plain radiography, abdominal ultrasonography (US), and magnetic resonance imaging (MRI) were requested. Blood count revealed anemia and neutrophilic leukocytosis and hypercalcemia. The liver showed increased echogenicity and thickened pancreas in the abdominal US scan. A slightly heterogeneous, vascularized mass with irregular borders was identified in the topographic region of the sublumbar lymph nodes; MRI images demonstrated an expansile formation in the ventral region of the lumbosacral spine, corresponding to the sublumbar lymph nodes and interruption of the cerebrospinal fluid at L5, suggestive of compression of the spinal cord and cauda equina. A presumptive diagnosis of perianal neoplasm with metastasis was made based on the complementary exams. The dog was referred to necropsy, which revealed a 4 cm tumor in the perianal region that invaded the pelvic canal. Multifocal nodules were present on the lung surface, liver, and kidneys, suggesting metastasis. On the cross-section of the spine, one could note the presence of the tumor in the vertebral bodies, spinal cord, and cauda equina from L5 to S3. Even with histopathological evaluation of the tumor, only the immunohistochemical analysis allowed us to confirm the anal sac adenocarcinoma. Discussion: Adenomas and carcinomas are perianal gland neoplasms common in adult and elderly male dogs; the Cocker Spaniel breed is among the most affected. The clinical signs presented by the patient, such as tenesmus and difficulty in adopting the posture of defecation, are common, although neurological changes are rare. As for metastasis, carcinomas of the perianal region present high chances of metastasis to organs including the liver, kidneys, and lungs, both lymphatically and hematogenously, but few studies have related these factors to neurological alterations due to metastasis. We concluded that metastases from carcinomas to the spine must be considered a possible differential diagnosis in cases of patients presenting clinical signs that are compatible with spinal cord compression and a history of previous neoplasm.

Cutaneous myxoma in broiler chicken detected during slaughtering

Background: A cutaneous or superficial myxoma is a benign neoplasm of dermal or subcutaneous fibroblast origin. Although rare, it has been previously described in several species, including poultry. It presents as a single node or soft mass with a gelatinous cut surface. Histopathological analysis is essential for diagnosis and to differentiate it from other mesenchymal neoplasms and inflammatory or degenerative processes. Microscopically, it consists of dermal or subcutaneous lobules of plump, stellate, or spindle-shaped, bland-looking cells embedded in a basophilic myxoid matrix. This report describes the pathological findings in a rare case of cutaneous myxoma in a 42-day-old broiler flock. Cases: During ante mortem inspection of a 42-day-old broiler flock at a slaughterhouse under the authority of the Federal Inspection Service (southern Brazil), nodular lesions or encrusted areas with yellow and black areas were observed in the head skin of less than 1% of animals. These lesions, approximately 0.5 cm in diameter, were observed on the comb, in the periocular skin region, and close to the animals' nostrils. During the breeding period, no health or epidemiological events were observed. Fragments of the lesions in the comb and periocular skin were collected and fixed in buffered 10% formalin. The samples were sent to the laboratory, routinely processed, and stained with hematoxylin and eosin and Alcian blue. Microscopically, the lesions consisted of irregular multifocal proliferation of connective tissue showing spindle cells with poorly demarcated borders and scarce cytoplasm in a slightly basophilic myxoid aspect matrix. The adjacent epidermis is compressed due to neoplastic proliferation. No areas of epithelial hyperplasia or inclusion bodies were observed. According to the pathologic description and considering its descriptive epidemiology, our main clinical suspicion was cutaneous fowl pox, a pathology characterized by the appearance of nodules in regions devoid of feathers. However, the microscopic changes observed were compatible with those described for cutaneous myxomas. In addition, the extracellular matrix was positive for Alcian Blue staining, which is an indicator of myxoma. In the present case, the SIF did not report the same macroscopic lesions in other flocks of the same origin. Discussion: Connective tissue tumors, including myxomas, occur considerably less frequently under field conditions. In addition, these neoplasms are more frequent in mature birds and are not usually described in broilers, as observed in this report. The cutaneous myxoma described in broilers is usually a sporadic neoplasm that does not cause zootechnical losses, as observed in the case report. Its etiology is unknown and has been associated with various factors, such as local trauma and foreign bodies. Some fragments of plant material from the breeding environment were microscopically detected in the encrusted areas, which may indicate previous trauma or a foreign body. Myxoma has been associated with avian leukosis virus (ALV) subgroup A, but SIF did not report the same macroscopic lesions in other flocks of the same breeder hen's origin in the present case. Furthermore, sporadic connective tissue tumors associated with the virus occur in mature chickens but not in broilers. Myxoma lesions should be considered in the differential diagnosis of other connective tissue tumors and infectious agents that cause lesions in the skin and subcutaneous tissue.

Carcinoma de células escamosas corneal em um cão - uso da Mitomicina C 0, 02% como adjuvante no tratamento / Corneal squamous cell carcinoma in a dog - use of Mitomycin C 0. 02% as an adjuvant therapy

Background: Although Squamous Cell Carcinoma (SCC) is most commonly seen in the epidermis, this malignant neoplasm can manifest in various other tissues. A wide range of factors may be related to the development of SCC in the cornea, with continuous exposure to ultraviolet radiation and chronic friction to the ocular surface being the most accepted theories. In addition to surgical procedures, the use of mitomycin C in the topical treatment of corneal SCC has shown good results in therapeutic management. Thus, the objective of the current work is to report the satisfactory response observed in the use of mitomycin C in a case of SCC in the cornea of a dog. Case: A 9-year-old male Pug dog was attended by the Veterinary Ophthalmology and Microsurgery Sector (SOMVET) of the University Veterinary Hospital (HVU) of the Federal University of Santa Maria (UFSM) with Squamous Cell Carcinoma (SCC) in the cornea of the left eye, which had recurred after a previous surgical intervention. Secretion and discomfort in the left eye were noted during clinical examination. In addition, both eyes presented pigmentary keratitis in the medial corner. Surgical excision of the neoplasm was performed using the surgical technique of anterior lamellar keratectomy. In the immediate postoperative period, topical therapy was started with eye drops based on mitomycin C at 0.02%, for a period of 28 consecutive days. The use of this chemotherapy drug in the topical form was intended to minimize the chances of recurrence of the clinical condition, since the patient is predisposed to this alteration. In addition, supportive therapy was implemented to improve patient comfort, consisting of the use of tobramycin-based eye drops (6 times a day, for 14 days), atropine 1% eye drops (BID, for 3 days), lubricating eye drops based on sodium hyaluronate (3 times a day, for continuous use), and immunomodulatory eye drops based on tacrolimus 0.02% (twice a day, for continuous use). The patient was evaluated 7, 14, 21, and 28 days after surgery, when good results were observed. One year after treatment, the dog was still showing no signs of recurrence of the treated clinical condition. Discussion: It is known that chronic friction on the surface of the cornea predisposes to the diagnosis of corneal SCC. Accordingly, in the clinical examination of the patient in this report, the presence of bilateral pigmentary keratitis was observed, an alteration that leads to a framework of chronic aggression to the cornea. Surgical treatment is recommended to remove the tumor mass in the ocular region. However, in cases of corneal SCC, the literature highlights that recurrence after surgical excision is a common factor. As the patient in this study arrived at the clinic with a history of recurrence, topical therapy with mitomycin C associated with surgical treatment was instituted. This chemotherapy drug has shown encouraging results in the treatment of some neoplasms, especially SCC. Its use in this case supported previous findings, pointing to a satisfactory result in which the patient had no recurrences after one year of follow-up. In addition, the concentration and frequency used of the active ingredient did not lead to adverse effects in the short or medium term.

Epididymal primary mast cell tumor in a dog

Background: In the literature, there are a few descriptions of epididymis neoplasia in domestic animals, especially considering primary tumors. In the few reports found in literature, the lesions were a consequence of the invasion of testicular or paratesticular neoplasia, as a papillar carcinoma in a dog's and a bull's epididymis, and mesenchymal tumors - fibrome/ fibrosarcoma, leiomyoma/leiosarcome. On the other hand, mast cell tumors are the second most prevalent neoplasia in dogs in Brazil, affecting especially the skin. The aim of this report is to describe for the first time a low malignancy mast cell tumor in a mixed-breed dog's epididymis, without metastasis or recurrence in a 2-year follow-up period. Case: A 10-year-old male mixed-breed dog was presented for pre-surgical evaluation for elective orchiectomy. In the physical examination, an increase in the volume of approximately 2 cm with an irregular appearance was identified on palpation in the cranial pole of the left testis. In the trans surgical period, an increase in testicular volume (4 cm long x 2 cm wide) was observed, with a firm consistency in the region of the vas deferens with macroscopic changes in the region. The testis was sectioned, and the fragments were sent for histopathological evaluation in 10% buffered formaldehyde. There was a fairly cellular circumscribed neoplastic infiltrate, distributed in a sheet and separated by fibrovascular stroma, and rounded neoplastic cells with a moderate amount of basophilic cytoplasmic granulation, and discrete anisocytosis and anisokaryosis. The nuclei were rounded with vesicular chromatin with 1 or 2 distinct nucleoli. No mitosis figures were observed in 10 high power fields (400x). Few eosinophils were distributed throughout the neoplastic cell population. Immunohistochemistry demonstrated immunostaining for KIT protein with perimembranous staining in 95% of neoplastic mast cells, giving a KIT 1 pattern. There was no positive nuclear staining for Ki67 in any cell of the histological sections examined. A grade II mast cell tumor (low grade of malignancy) was diagnosed. After diagnosis, the animal underwent radiographic evaluation of the chest and abdominal ultrasound, and a new physical inspection in search of nodules, plaques, skin lesions, or subcutaneous masses. There were no metastases in the thorax and abdominal cavity, nor physical alterations, and it can be inferred that the epididymis was the primary site of the mast cell tumor. After 2 years of orchiectomy, there were no recurrences, and no chemotherapy treatment was performed. Discussion: Extracutaneous mast cell tumors are uncommon in animals, but have been reported in oral and nasal mucosa, nasopharynx, larynx, trachea, intestine, visceral lymph nodes, spleen, liver, spinal cord, intestine, ureter, conjunctiva, lung and more recently in tear gland of the third eyelid. However, in the authors' assessment, this is the first description of mast cell tumor in the epididymis in dogs. The diagnosis was established by histopathological examination, which revealed a grade II epididymal mast cell tumor and immunohistochemical evaluation (KIT and Ki-67) as being of low aggressiveness. The diagnosis of a primary tumor was confirmed since the staging was established after the histopathological diagnosis, involving chest radiography, abdominal ultrasound, cutaneous evaluation in search of nodules, plaques, cutaneous and subcutaneous lesions, and did not reveal other abnormalities or metastases not identified in the preoperative evaluation. In addition, immunostaining with KIT and Ki-67 reaffirmed the low degree of malignancy and the potential for metastases, which can be observed by the asymptomatic follow-up of the patient 2 years after the surgical excision.

Canine mixed tumors as one of the mammary neoplasia varieties

The most significant interest in veterinary oncology is occupied by tumors of a mixed nature, which are represented by the direct interaction of epithelial and mesenchymal components. According to some data, the formation of cell lineage of mesenchymal cells occurs due to the transformation of epidermal basket cells surrounding the glandular epithelium. In this case, the formation of a cartilage anlage with its further transformation into differentiated bone tissue occurs. The article contains information about the structure and features of the location and interaction of mixed tumors' glandular and stromal components in female dogs (n=29). It was revealed that in addition to simple mixed neoplasms, tumors with proplasia of the mesenchymal component into highly differentiated cartilage or bone tissue were also often registered. To confirm subcellular changes in the expression of certain types of proteins, such as a-SMA and vimentin, an IHC study was used. The expression of the studied biomarkers was established in mesenchymal fibroblastic differon cells and myoepithelial cells. The intensity of immunoreactive material expression ranged from moderate (2+) to strong (3+), indicating changes in myoepithelial cells' genotype during the formation of mixed mammary neoplasms.(AU)