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)

Non-teratoid ocular medulloepithelioma in an adult horse / Meduloepitelioma ocular não-teratóide em um equino adulto

This is a case of medulloepithelioma in a 14-year-old mixed breed gelding horse, presenting a large abnormal mass of tissue involving the entire extension of the right eye. Ophthalmic examination showed deformation and swelling of the eye. The animal showed signs of pain on palpation of the organ, but the specific examination of the systems did not reveal any other changes. Due to the extension of the apparently neoplastic mass and the discomfort experienced by the animal, transpalpebral enucleation procedure was decided. The excised tissue was sent for histopathological analysis, wherein a neoplastic proliferation of neuroectodermal cells was noted. The neoplasm was poorly delimited, unencapsulated, infiltrative, sustained by moderate fibrovascular stroma, and formed cords and rosettes with cells arranged in palisades around the luminal structures (Flexner-Wintersteiner rosettes), suggestive of medulloepithelioma. The immunohistochemical profile was also performed, confirming the diagnosis. The neoplastic cells were immunolabeled to vimentin, S100 protein (S100), and specific neuro enolase (NSE), but not for pan cytokeratin (AE1AE3), glial fibrillary acidic protein (GFAP), and cytokeratin 8/18 (CK8/18). Five months postoperatively, the animal was healthy, without any relapse or evidence of metastasis.(AU)

Esse é um caso de meduloepitelioma em um equino sem raça definida, castrado, de 14 anos de idade, que chegou ao atendimento apresentando grande massa de tecido envolvendo toda a extensão do olho direito. No exame oftálmico, foi observada deformação e aumento de volume ocular. O animal manifestou sinais de dor na palpação do órgão, mas o exame específico dos sistemas não revelou demais alterações. Devido à extensão da massa aparentemente neoplásica e o desconforto experimentado pelo equino foi decidida a realização da enucleação transpalpebral. O tecido excisado foi enviado para exame histopatológico, no qual observou-se proliferação neoplásica de células neuroectodérmicas, de forma mal delimitada, não encapsulada, infiltrativa, sustentada por estroma fibrovascular moderado, e formação de cordões e rosetas, com células dispostas em paliçadas ao redor de estruturas luminais (rosetas de Flexner-Wintersteiner), sugestivo de meduloepitelioma. O perfil imunohistoquímico também foi realizado, confirmando o diagnóstico. As células neoplásicas foram imunomarcadas para vimentina, proteína S100 (S100) e neuro enolase específica (NSE), mas não para pan citoqueratina (AE1AE3), proteína glial fibrilar ácida (GFAP) e citoqueratina 8/18 (CK8 / 18). Após cinco meses da realização do procedimento cirúrgico o animal apresentava-se saudável, sem recidiva ou evidência de metástase.(AU)

Ophthalmological and neurological manifestations of a dog with intracranial anaplastic ependymoma. Case report / Manifestações oftalmológicas e neurológicas em um cão com ependimoma anaplásico intracranial: relato de caso

The objective is to report ependymoma associated with uveitis in a four-month-old male boxer crossbreed. The dog initially presented in both eyes conjunctival hyperemia, blepharospasm, projection of the nictitating membrane, and photophobia, characteristic of uveitis.Traumatic uveitis was rejected. Six days after onset of ophthalmic symptoms, vomiting, incoordination, and behavior changes occurred. Neurological symptoms and eyebrow contraction suggesting head pain and brain injury were investigated by computed tomography (CT) nine days after, when the dog showed spasms of the limbs and neck followed by respiratory arrest with reversal and stabilization. The scans revealed extensive amorphic neoformation in the diencephalon, midbrain, and within the right lateral ventricle, along with sinistral displacement of the cerebral sickle. The animal was euthanized, and necropsy of the head revealed hydrocephalus and an intracerebral tumor mass consistent with the CT imaging. Histopathological evaluation by hematoxylin and eosin staining revealed tissue alterations in several CNS segments, showing several pseudorosettes in the neuropil, mitosis, and a high degree of cell atypia, indicating ependymoma. Inflammatory, hemorrhagic, and necrotic tissue lesions were observed in the brainstem and cerebellum due to compression by tumor tissue and hydrocephalus. The neoplasia was phenotyped by Immunohistochemistry (IHC), and tested positive for the tumoral markers vimentin and glial fibrillary acid protein, confirming intracranial anaplastic ependymoma. Behavior changes and neurological signs resulted from vascular, inflammatory, and degenerative processes in the neuropil caused by neoplasm compression and invasion of brain tissue. Although dogs with ependymoma often present with neurological disease, in the present case, blepharospasm was the first symptom noticed by the owner, and it persisted until euthanasia. According to the literature, and confirmed in the evolution of the current case, the symptoms are related to tumor location and extent and to secondary lesions due to tumor expansion. Clinical symptomatology and complementary laboratory testing, CT, necropsy, histology, and IHC characterized ependymoma, a rare condition in young dogs.

Objetiva-se relatar um caso de ependimoma anaplásico associado a uveíte em cão macho de quatro meses de idade, mestiço Boxer. O cão apresentou, inicialmente, hiperemia conjuntival, blefaroespasmo, projeção da membrana nictitante e fotofobia bilaterais, sinais característicos de uveíte. Uveíte por causa traumática foi descartada. Seis dias após o início dos sintomas oftálmicos ocorreram vômito, incoordenação motora e alterações de comportamento. Sinais neurológicos e contração das sobrancelhas sugeriram algia na região cefálica. Injúria cerebral foi investigada por tomografia computadorizada (TC) nove dias após o início dos sintomas, quando o cão demonstrou espasmos dos membros e pescoço, seguido por parada respiratória com reversão e estabilização. A TC revelou extensa e amórfica neoformação no diencéfalo, mesencéfalo, e dentro do ventrículo lateral direito, com deslocamento à esquerda da foice cerebral. O animal foi eutanasiado e a necropsia revelou hidrocefalia e uma massa tumoral intracerebral condizente com a imagem da TC. A avaliação histopatológica por coloração hematoxilina e eosina, revelou alterações teciduais em várias áreas do Sistema Nervoso Central (SNC), mostrando várias pseudorosetas no neurópilo, mitose, e um elevado grau de atipia celular, indicando ependimoma.Lesões teciduais inflamatórias, hemorrágicas e necróticas foram observadas no tronco encefálico e cerebelo, devido à compressão do tumor e à hidrocefalia. Amostras da neoplasia foram submetidas à análise imuno-histoquímica (IHQ), sendo positiva a expressão dos marcadores tumorais vimentina e proteína glial fibrilar ácida, confirmando ependimoma anaplásico intracranial. As mudanças comportamentais e sinais neurológicos resultaram do processo vascular, inflamatório e degenerativo no neurópilo, causados pela compressão e invasão do tecido cerebral pela neoplasia. Embora cães com ependimoma frequentemente apresentem manifestações neurológicas, no presente caso, blefaroespasmo foi o primeiro sinal clínico observado pelo proprietário, e persistiu até a eutanásia do paciente. Os sinais neurológicos estão relacionados à localização do tumor e extensão das lesões secundárias devidas à sua expansão. Sintomatologia clínica e testes laboratoriais complementares, TC, necropsia, histologia e IHQ caracterizaram ependimoma, que é raro em animais jovens.

Ophthalmological and neurological manifestations of a dog with intracranial anaplastic ependymoma. Case report / Manifestações oftalmológicas e neurológicas em um cão com ependimoma anaplásico intracranial: relato de caso

The objective is to report ependymoma associated with uveitis in a four-month-old male boxer crossbreed. The dog initially presented in both eyes conjunctival hyperemia, blepharospasm, projection of the nictitating membrane, and photophobia, characteristic of uveitis.Traumatic uveitis was rejected. Six days after onset of ophthalmic symptoms, vomiting, incoordination, and behavior changes occurred. Neurological symptoms and eyebrow contraction suggesting head pain and brain injury were investigated by computed tomography (CT) nine days after, when the dog showed spasms of the limbs and neck followed by respiratory arrest with reversal and stabilization. The scans revealed extensive amorphic neoformation in the diencephalon, midbrain, and within the right lateral ventricle, along with sinistral displacement of the cerebral sickle. The animal was euthanized, and necropsy of the head revealed hydrocephalus and an intracerebral tumor mass consistent with the CT imaging. Histopathological evaluation by hematoxylin and eosin staining revealed tissue alterations in several CNS segments, showing several pseudorosettes in the neuropil, mitosis, and a high degree of cell atypia, indicating ependymoma. Inflammatory, hemorrhagic, and necrotic tissue lesions were observed in the brainstem and cerebellum due to compression by tumor tissue and hydrocephalus. The neoplasia was phenotyped by Immunohistochemistry (IHC), and tested positive for the tumoral markers vimentin and glial fibrillary acid protein, confirming intracranial anaplastic ependymoma. Behavior changes and neurological signs resulted from vascular, inflammatory, and degenerative processes in the neuropil caused by neoplasm compression and invasion of brain tissue. Although dogs with ependymoma often present with neurological disease, in the present case, blepharospasm was the first symptom noticed by the owner, and it persisted until euthanasia. According to the literature, and confirmed in the evolution of the current case, the symptoms are related to tumor location and extent and to secondary lesions due to tumor expansion. Clinical symptomatology and complementary laboratory testing, CT, necropsy, histology, and IHC characterized ependymoma, a rare condition in young dogs.(AU)

Objetiva-se relatar um caso de ependimoma anaplásico associado a uveíte em cão macho de quatro meses de idade, mestiço Boxer. O cão apresentou, inicialmente, hiperemia conjuntival, blefaroespasmo, projeção da membrana nictitante e fotofobia bilaterais, sinais característicos de uveíte. Uveíte por causa traumática foi descartada. Seis dias após o início dos sintomas oftálmicos ocorreram vômito, incoordenação motora e alterações de comportamento. Sinais neurológicos e contração das sobrancelhas sugeriram algia na região cefálica. Injúria cerebral foi investigada por tomografia computadorizada (TC) nove dias após o início dos sintomas, quando o cão demonstrou espasmos dos membros e pescoço, seguido por parada respiratória com reversão e estabilização. A TC revelou extensa e amórfica neoformação no diencéfalo, mesencéfalo, e dentro do ventrículo lateral direito, com deslocamento à esquerda da foice cerebral. O animal foi eutanasiado e a necropsia revelou hidrocefalia e uma massa tumoral intracerebral condizente com a imagem da TC. A avaliação histopatológica por coloração hematoxilina e eosina, revelou alterações teciduais em várias áreas do Sistema Nervoso Central (SNC), mostrando várias pseudorosetas no neurópilo, mitose, e um elevado grau de atipia celular, indicando ependimoma.Lesões teciduais inflamatórias, hemorrágicas e necróticas foram observadas no tronco encefálico e cerebelo, devido à compressão do tumor e à hidrocefalia. Amostras da neoplasia foram submetidas à análise imuno-histoquímica (IHQ), sendo positiva a expressão dos marcadores tumorais vimentina e proteína glial fibrilar ácida, confirmando ependimoma anaplásico intracranial. As mudanças comportamentais e sinais neurológicos resultaram do processo vascular, inflamatório e degenerativo no neurópilo, causados pela compressão e invasão do tecido cerebral pela neoplasia. Embora cães com ependimoma frequentemente apresentem manifestações neurológicas, no presente caso, blefaroespasmo foi o primeiro sinal clínico observado pelo proprietário, e persistiu até a eutanásia do paciente. Os sinais neurológicos estão relacionados à localização do tumor e extensão das lesões secundárias devidas à sua expansão. Sintomatologia clínica e testes laboratoriais complementares, TC, necropsia, histologia e IHQ caracterizaram ependimoma, que é raro em animais jovens.(AU)

Peripheral nerve sheath tumor in the upper eyelid in a dog

Background: Peripheral nerve sheath tumors are most commonly found on the head and neck regions of both dogs and people. Schwannomas are rarely observed in ophthalmic areas. When they occur, ocular Schwannomas are usually located in the orbit, uveal tract and conjunctiva. The occurrence of uveal schwannoma, a subset of PNST has been well documented in the veterinary literature. PNST has never been observed in the eyelids of dogs. Therefore, the present report aimed to describe the surgical treatment and outcome of a PNST located in the upper eyelid of a dog. Case: A 9-year-old, spayed female mixed-breed dog was referred for evaluation of a large mass involving the right upper eyelid for a duration of approximately one month. The inspection revealed sero-sanguinolent discharge and an oval-shaped mass occupying more than 70% of the right upper eyelid. A presumptive diagnosis of eyelid neoplasia was considered most likely. Excision of the entire mass with a 2 cm margin was performed. The third eyelid and dorso-medial bulbar conjunctiva were also removed. Upper eyelid reconstruction was performed based on a similar technique previously described in cats (lip-to-lid flap). As a result, neoplastic spindle cells exhibited immunoreactivity for S100 and intense cytoplasmic staining for vimentin, supporting the diagnosis of schwannoma. Fifteen days later, the margins of the subdermal pattern flap were healed and skin sutures were removed. On the last follow-up, 9 months post-surgery, the dog was visual, and the flap was well incorporated and covered the ocular surface. Ten months later, another large mass arising from the right inferior palpebral conjunctiva was observed. Once ultrasound revealed orbital invasion exenteration combined with orbitectomy were performed, and the defect was covered with an auricular axial pattern flap. The second tumor had the same histological and immunohistochemical characteristics of the first mass. Both tumors expressed Ki67; however, the PI in the second mass was higher (7.9%) than the first (3.4%). Discussion: Reported eyelid neoplasms in dogs include adenomas and adenocarcinomas of the meibomian glands, melanomas, fibroma, fibrosarcoma, histiocytoma, mastocytoma, lipomas, papillomas, and squamous cell carcinomas. To the author's knowledge, however, this is the first case description of a PNST affecting the eyelid in a dog. The histologic distinction between PNSTs and other spindle cell tumors, including myxosarcoma, fibrosarcoma, leiomyosarcoma, hemangiopericytoma, and melanoma can be challenging and requires immunohistochemical stainin. S100 is an acidic protein that identifies various nervous tissue cells, including Schwann cells, and the majority of canine PNSTs diffusely express this molecule. As in the case presented here, neoplastic cells of different ocular and adnexal structures were also positive for S100 and vimentin in all PNSTs previously reported in the veterinary literature. This is the first report of PNST affecting the eyelid in a dog. The lip-to-lid flap is a feasible technique to reconstruct the upper eyelid following wide surgical removal of a tumor in dogs. However, the authors suggest radical surgery combining orbitectomy, exenteration and a miocutaneous flap if PNST is diagnosed in the eyelids of dogs. They also caution once recurrence is possible and can be more aggressive.(AU)

Cutaneous myofibroblastic fibrosarcoma in a margay (Leopardus wiedii): a case report

A routine check-up was performed on a captive 14-year-old female margay (Leopardus wiedii), a cutaneous mass was detected on the ventral thorax. The mass was surgically removed and sent for histopathological analysis. Histologically, the mass was a poorly-demarcated, highly cellular, infiltrative and unencapsulated mesenchymal neoplasm. Immunohistochemical labeling for smooth muscle actin and vimentin were positive, while desmin and cytokeratin were negative which is consistent with a myofibroblastic fibrosarcoma. This type of tumor has been diagnosed in wild felines, however this seems to be the first report of its occurrence in this L. wiedii. Wildlife oncology studies should be performed to promote our understanding of cancer in a species.

Cutaneous myofibroblastic fibrosarcoma in a margay (Leopardus wiedii): a case report

A routine check-up was performed on a captive 14-year-old female margay (Leopardus wiedii), a cutaneous mass was detected on the ventral thorax. The mass was surgically removed and sent for histopathological analysis. Histologically, the mass was a poorly-demarcated, highly cellular, infiltrative and unencapsulated mesenchymal neoplasm. Immunohistochemical labeling for smooth muscle actin and vimentin were positive, while desmin and cytokeratin were negative which is consistent with a myofibroblastic fibrosarcoma. This type of tumor has been diagnosed in wild felines, however this seems to be the first report of its occurrence in this L. wiedii. Wildlife oncology studies should be performed to promote our understanding of cancer in a species.(AU)

Pathological and immunohistochemical aspects of primary hepatobiliary neoplasms in cats

ABSTRACT: Primary hepatobiliary neoplasms (PHN) are uncommon in cats, and originate in hepatocytes, intra- and extrahepatic bile ducts, mesenchymal cells, and cells of neuroendocrine origin. The aim of this study was to determine the frequency of PHN in cats diagnosed in the metropolitan region of Porto Alegre (RS), Brazil, for a period of 17 years, determining their epidemiological, anatomopathological and immunohistochemical aspects. Necropsy reports of 2.090 cats were analyzed, 125 were diagnosed with primary hepatobiliary diseases, of which 15 were cases of PHN, representing 12% of the specific hepatobiliary conditions and 0.7% of the necropsies. All PHN were malignant, of which 93.3% had epithelial origin and 6.7% presented mesenchymal origin. Cholangiocarcinoma was the most commonly diagnosed neoplasm, followed by hepatocellular carcinoma and hemangiosarcoma. In general, cats with no defined breed were the most affected. Concerning sex, 60% were females and 40% males. Age ranged from five to 18 years, with a mean age of 10.5 years (median of ten years). Grossly, cholangiocarcinoma and hemangiosarcoma were multinodular and hepatocellular carcinoma was massive. Microscopically, cholangiocarcinomas were arranged in acini and ducts, whereas hepatocellular carcinomas were arranged in solid sheets or trabeculae. On immunohistochemistry, cholangiocarcinomas, hepatocellular carcinomas, and hemangiosarcomas were positive for the antibodies CK 7, Hep Par-1, and vimentin and von Willebrand factor, respectively.

RESUMO: Neoplasias hepatobiliares primárias (NHP) são incomuns em gatos e se originam de hepatócitos, células dos ductos biliares intra e extra-hepáticos, células mesenquimais e ainda células de origem neuroendócrina. O objetivo do trabalho foi determinar a frequência das NHP em gatos diagnosticados na Região Metropolitana de Porto Alegre, no período de 17 anos, abordando seus aspectos epidemiológicos, anatomopatológicos e imuno-histoquímicos (IHQ). Foram analisados os laudos de necropsia de 2.090 gatos sendo que 125 foram diagnosticados com doenças hepatobiliares primárias, destes 15 foram casos de NHP, representando 12% das condições hepatobiliares específicas e 0,7% do total de necropsias. Todos os diagnósticos de NHP eram malignos, destes 93,3% apresentaram origem epitelial e 6,7% mesenquimal. Colangiocarcinoma foi a neoplasia mais diagnosticada, seguido do carcinoma hepatocelular e hemangiossarcoma. De uma maneira geral, os gatos sem raça definida foram os mais acometidos. Em relação ao sexo 60% eram fêmeas e 40% machos. A idade variou de cinco a 18 anos, com a idade média de 10,5 anos (mediana de 10 anos). Macroscopicamente o colangiocarcinoma e hemangiossarcoma eram multinodulares, e o carcinoma hepatocelular, maciço. À histologia, houve predomínio do arranjo acinar e ductal nos colangiocarcinomas e sólido, no carcinoma hepatocelular. Na IHQ os colangiocarcinomas foram reativos para CK 7, carcinoma hepatocelular para Hep Par-1 e hemangiossarcoma para vimentina e fator de von Willebrand.

Primary nonlymphoid gastrointestinal neoplasms in dogs in Rio Grande do Sul

ABSTRACT: Gastrointestinal neoplasms (GIN) are uncommon in dogs, but they mainly show malignant behavior and poor prognosis. The types of GIN in dogs and their frequency, as well as their epidemiological and histopathological characteristics were analyzed through a retrospective study of biopsies from 24.711 dogs from 2005 to 2017. Additionally, histological sections of neoplasms were subjected to immunohistochemistry (IHC) using antibodies against pancytokeratin, vimentin, smooth muscle actin, c-Kit, S-100, CD31, CD79cy, and neuron-specific enolase. Of the total samples from dogs analyzed, 88 corresponded to GIN. Neoplasms occurred more frequently in purebred dogs (64.8%, 57/88), males (53.4%, 47/88), with a median age of 10 years. The intestine was affected by 84.1% (74/88) of the cases. Of these, the large intestine was the most affected (67.6%, 50/74). Most of the neoplasms had malignant behavior (88.6%, 78/88). Regarding the classification of neoplasms, 46.6% (41/88) of the diagnoses corresponded to epithelial, 46.6% (41/88) were mesenchymal, 5.7% (5/88) were hematopoietic, and 1.1% (1/88) was neuroendocrine. The most frequently diagnosed neoplasms were papillary adenocarcinoma (19.3%, 17/88), leiomyosarcoma (17.0%, 15/88), gastrointestinal stromal tumors (GISTs) (12.5%, 11/88), and leiomyoma (5.0%, 8/88). Adenocarcinomas were located mainly in the rectum, whereas leiomyosarcomas and GISTs developed mainly in the cecum. Epithelial neoplasms showed a greater potential for lymphatic invasion whereas mesenchymal neoplasms appeared to be more expansive with intratumoral necrosis and hemorrhage. Immunohistochemistry was found to be an important diagnostic technique for the identification of infiltrating cells in carcinomas and an indispensable technique for the definitive diagnosis of sarcomas.

RESUMO: Neoplasmas gastrointestinais (NGI) são pouco comuns em cães, mas possuem principalmente comportamento maligno e prognóstico reservado. Os tipos de NGI em cães e sua frequência, bem como características epidemiológicas e histopatológicas foram analisados por meio de um estudo retrospectivo dos exames de biópsias de 24.711 cães entre os anos de 2005 a 2017. Adicionalmente, cortes histológicos de NGI foram submetidos à técnica de imuno-histoquímica (IHQ), utilizando os anticorpos anti-pancitoqueratina, vimentina, actina de músculo liso, c-Kit, S-100, CD31, CD79cy e enolase neurônio específica. Do total de cães analisados, 88 corresponderam a NGI não linfoides. Os neoplasmas ocorreram com maior frequência em cães de raça pura (64,8%, 57/88), machos (53,4%, 47/88), com mediana de idade de 10 anos. O intestino foi acometido em 84,1% dos casos (74/88). Destes, o intestino grosso foi o segmento mais afetado (67,6%, 50/74). A maior parte dos neoplasmas tinha comportamento maligno (88,6%, 78/88). Quanto à classificação, 46,6% (41/88) dos diagnósticos corresponderam a neoplasmas epiteliais, 46,6% (41/88) mesenquimais, 5,7% (5/88) hematopoiéticos e 1,1% (1/88), neuroendócrino. Os neoplasmas mais frequentemente diagnosticados foram adenocarcinoma papilar (19,3%, 17/88), leiomiossarcoma (17,0%, 15/88), tumor estromal gastrointestinal (GIST) (12,5%, 11/88) e leiomioma (12,5%, 8/88). Adenocarcinomas localizavam-se principalmente no reto, enquanto leiomiossarcoma e GISTs desenvolveram-se principalmente no ceco. Os neoplasmas epiteliais demonstraram um potencial maior de invasão linfática enquanto que os mesenquimais aparentaram ser mais expansivos, com necrose e hemorragia intratumorais. A imuno-histoquímica mostrou ser uma técnica diagnóstica importante para a identificação de células neoplásicas infiltravas no caso dos carcinomas e uma técnica indispensável para o diagnóstico definitivo de sarcomas.

Pathological and immunohistochemical aspects of primary hepatobiliary neoplasms in cats / Aspectos patológicos e imuno-histoquímicos de neoplasias hepatobiliares primárias em gatos

Primary hepatobiliary neoplasms (PHN) are uncommon in cats, and originate in hepatocytes, intra- and extrahepatic bile ducts, mesenchymal cells, and cells of neuroendocrine origin. The aim of this study was to determine the frequency of PHN in cats diagnosed in the metropolitan region of Porto Alegre (RS), Brazil, for a period of 17 years, determining their epidemiological, anatomopathological and immunohistochemical aspects. Necropsy reports of 2.090 cats were analyzed, 125 were diagnosed with primary hepatobiliary diseases, of which 15 were cases of PHN, representing 12% of the specific hepatobiliary conditions and 0.7% of the necropsies. All PHN were malignant, of which 93.3% had epithelial origin and 6.7% presented mesenchymal origin. Cholangiocarcinoma was the most commonly diagnosed neoplasm, followed by hepatocellular carcinoma and hemangiosarcoma. In general, cats with no defined breed were the most affected. Concerning sex, 60% were females and 40% males. Age ranged from five to 18 years, with a mean age of 10.5 years (median of ten years). Grossly, cholangiocarcinoma and hemangiosarcoma were multinodular and hepatocellular carcinoma was massive. Microscopically, cholangiocarcinomas were arranged in acini and ducts, whereas hepatocellular carcinomas were arranged in solid sheets or trabeculae. On immunohistochemistry, cholangiocarcinomas, hepatocellular carcinomas, and hemangiosarcomas were positive for the antibodies CK 7, Hep Par-1, and vimentin and von Willebrand factor, respectively.(AU)

Neoplasias hepatobiliares primárias (NHP) são incomuns em gatos e se originam de hepatócitos, células dos ductos biliares intra e extra-hepáticos, células mesenquimais e ainda células de origem neuroendócrina. O objetivo do trabalho foi determinar a frequência das NHP em gatos diagnosticados na Região Metropolitana de Porto Alegre, no período de 17 anos, abordando seus aspectos epidemiológicos, anatomopatológicos e imuno-histoquímicos (IHQ). Foram analisados os laudos de necropsia de 2.090 gatos sendo que 125 foram diagnosticados com doenças hepatobiliares primárias, destes 15 foram casos de NHP, representando 12% das condições hepatobiliares específicas e 0,7% do total de necropsias. Todos os diagnósticos de NHP eram malignos, destes 93,3% apresentaram origem epitelial e 6,7% mesenquimal. Colangiocarcinoma foi a neoplasia mais diagnosticada, seguido do carcinoma hepatocelular e hemangiossarcoma. De uma maneira geral, os gatos sem raça definida foram os mais acometidos. Em relação ao sexo 60% eram fêmeas e 40% machos. A idade variou de cinco a 18 anos, com a idade média de 10,5 anos (mediana de 10 anos). Macroscopicamente o colangiocarcinoma e hemangiossarcoma eram multinodulares, e o carcinoma hepatocelular, maciço. À histologia, houve predomínio do arranjo acinar e ductal nos colangiocarcinomas e sólido, no carcinoma hepatocelular. Na IHQ os colangiocarcinomas foram reativos para CK 7, carcinoma hepatocelular para Hep Par-1 e hemangiossarcoma para vimentina e fator de von Willebrand.(AU)

Pathological and immunohistochemical aspects of primary hepatobiliary neoplasms in cats / Aspectos patológicos e imuno-histoquímicos de neoplasias hepatobiliares primárias em gatos

Primary hepatobiliary neoplasms (PHN) are uncommon in cats, and originate in hepatocytes, intra- and extrahepatic bile ducts, mesenchymal cells, and cells of neuroendocrine origin. The aim of this study was to determine the frequency of PHN in cats diagnosed in the metropolitan region of Porto Alegre (RS), Brazil, for a period of 17 years, determining their epidemiological, anatomopathological and immunohistochemical aspects. Necropsy reports of 2.090 cats were analyzed, 125 were diagnosed with primary hepatobiliary diseases, of which 15 were cases of PHN, representing 12% of the specific hepatobiliary conditions and 0.7% of the necropsies. All PHN were malignant, of which 93.3% had epithelial origin and 6.7% presented mesenchymal origin. Cholangiocarcinoma was the most commonly diagnosed neoplasm, followed by hepatocellular carcinoma and hemangiosarcoma. In general, cats with no defined breed were the most affected. Concerning sex, 60% were females and 40% males. Age ranged from five to 18 years, with a mean age of 10.5 years (median of ten years). Grossly, cholangiocarcinoma and hemangiosarcoma were multinodular and hepatocellular carcinoma was massive. Microscopically, cholangiocarcinomas were arranged in acini and ducts, whereas hepatocellular carcinomas were arranged in solid sheets or trabeculae. On immunohistochemistry, cholangiocarcinomas, hepatocellular carcinomas, and hemangiosarcomas were positive for the antibodies CK 7, Hep Par-1, and vimentin and von Willebrand factor, respectively.(AU)

Neoplasias hepatobiliares primárias (NHP) são incomuns em gatos e se originam de hepatócitos, células dos ductos biliares intra e extra-hepáticos, células mesenquimais e ainda células de origem neuroendócrina. O objetivo do trabalho foi determinar a frequência das NHP em gatos diagnosticados na Região Metropolitana de Porto Alegre, no período de 17 anos, abordando seus aspectos epidemiológicos, anatomopatológicos e imuno-histoquímicos (IHQ). Foram analisados os laudos de necropsia de 2.090 gatos sendo que 125 foram diagnosticados com doenças hepatobiliares primárias, destes 15 foram casos de NHP, representando 12% das condições hepatobiliares específicas e 0,7% do total de necropsias. Todos os diagnósticos de NHP eram malignos, destes 93,3% apresentaram origem epitelial e 6,7% mesenquimal. Colangiocarcinoma foi a neoplasia mais diagnosticada, seguido do carcinoma hepatocelular e hemangiossarcoma. De uma maneira geral, os gatos sem raça definida foram os mais acometidos. Em relação ao sexo 60% eram fêmeas e 40% machos. A idade variou de cinco a 18 anos, com a idade média de 10,5 anos (mediana de 10 anos). Macroscopicamente o colangiocarcinoma e hemangiossarcoma eram multinodulares, e o carcinoma hepatocelular, maciço. À histologia, houve predomínio do arranjo acinar e ductal nos colangiocarcinomas e sólido, no carcinoma hepatocelular. Na IHQ os colangiocarcinomas foram reativos para CK 7, carcinoma hepatocelular para Hep Par-1 e hemangiossarcoma para vimentina e fator de von Willebrand.(AU)

Primary nonlymphoid gastrointestinal neoplasms in dogs in Rio Grande do Sul / Neoplasmas gastrointestinais primários não linfoides em cães no Rio Grande do Sul

Gastrointestinal neoplasms (GIN) are uncommon in dogs, but they mainly show malignant behavior and poor prognosis. The types of GIN in dogs and their frequency, as well as their epidemiological and histopathological characteristics were analyzed through a retrospective study of biopsies from 24.711 dogs from 2005 to 2017. Additionally, histological sections of neoplasms were subjected to immunohistochemistry (IHC) using antibodies against pancytokeratin, vimentin, smooth muscle actin, c-Kit, S-100, CD31, CD79αcy, and neuron-specific enolase. Of the total samples from dogs analyzed, 88 corresponded to GIN. Neoplasms occurred more frequently in purebred dogs (64.8%, 57/88), males (53.4%, 47/88), with a median age of 10 years. The intestine was affected by 84.1% (74/88) of the cases. Of these, the large intestine was the most affected (67.6%, 50/74). Most of the neoplasms had malignant behavior (88.6%, 78/88). Regarding the classification of neoplasms, 46.6% (41/88) of the diagnoses corresponded to epithelial, 46.6% (41/88) were mesenchymal, 5.7% (5/88) were hematopoietic, and 1.1% (1/88) was neuroendocrine. The most frequently diagnosed neoplasms were papillary adenocarcinoma (19.3%, 17/88), leiomyosarcoma (17.0%, 15/88), gastrointestinal stromal tumors (GISTs) (12.5%, 11/88), and leiomyoma (5.0%, 8/88). Adenocarcinomas were located mainly in the rectum, whereas leiomyosarcomas and GISTs developed mainly in the cecum. Epithelial neoplasms showed a greater potential for lymphatic invasion whereas mesenchymal neoplasms appeared to be more expansive with intratumoral necrosis and hemorrhage. Immunohistochemistry was found to be an important diagnostic technique for the identification of infiltrating cells in carcinomas and an indispensable technique for the definitive diagnosis of sarcomas.(AU)

Neoplasmas gastrointestinais (NGI) são pouco comuns em cães, mas possuem principalmente comportamento maligno e prognóstico reservado. Os tipos de NGI em cães e sua frequência, bem como características epidemiológicas e histopatológicas foram analisados por meio de um estudo retrospectivo dos exames de biópsias de 24.711 cães entre os anos de 2005 a 2017. Adicionalmente, cortes histológicos de NGI foram submetidos à técnica de imuno-histoquímica (IHQ), utilizando os anticorpos anti-pancitoqueratina, vimentina, actina de músculo liso, c-Kit, S-100, CD31, CD79αcy e enolase neurônio específica. Do total de cães analisados, 88 corresponderam a NGI não linfoides. Os neoplasmas ocorreram com maior frequência em cães de raça pura (64,8%, 57/88), machos (53,4%, 47/88), com mediana de idade de 10 anos. O intestino foi acometido em 84,1% dos casos (74/88). Destes, o intestino grosso foi o segmento mais afetado (67,6%, 50/74). A maior parte dos neoplasmas tinha comportamento maligno (88,6%, 78/88). Quanto à classificação, 46,6% (41/88) dos diagnósticos corresponderam a neoplasmas epiteliais, 46,6% (41/88) mesenquimais, 5,7% (5/88) hematopoiéticos e 1,1% (1/88), neuroendócrino. Os neoplasmas mais frequentemente diagnosticados foram adenocarcinoma papilar (19,3%, 17/88), leiomiossarcoma (17,0%, 15/88), tumor estromal gastrointestinal (GIST) (12,5%, 11/88) e leiomioma (12,5%, 8/88). Adenocarcinomas localizavam-se principalmente no reto, enquanto leiomiossarcoma e GISTs desenvolveram-se principalmente no ceco. Os neoplasmas epiteliais demonstraram um potencial maior de invasão linfática enquanto que os mesenquimais aparentaram ser mais expansivos, com necrose e hemorragia intratumorais. A imuno-histoquímica mostrou ser uma técnica diagnóstica importante para a identificação de células neoplásicas infiltravas no caso dos carcinomas e uma técnica indispensável para o diagnóstico definitivo de sarcomas.(AU)

Meningioma microcístico com metástase pulmonar em canino: relato de caso / Microcystic meningioma with pulmonary metastasis in canine: case report

Meningiomas são os principais tumores primários do sistema nervoso central (SNC) que afetam cães e gatos. Na maioria dos casos, são neoplasias benignas, geralmente expansivas, causando compressão do SNC, e raramente fazem metástase para outros órgãos. O presente trabalho tem como objetivo relatar a ocorrência de um meningioma microcístico com metástase pulmonar em um canino de 11 anos de idade, com sinais clínicos de andar cambaleante, compressão da cabeça contra objetos, agitação, salivação e agressividade. Na necropsia, foram observadas, no encéfalo, massas bem delimitadas pardo-avermelhadas, firmes, de aspecto granular, localizadas no córtex parietal e nos núcleos da base. Inúmeras micronodulações de aspecto semelhante foram observadas no pulmão. Histologicamente observaram-se nódulos formados por células neoplásicas fusiformes, com núcleos grandes e alongados e nucléolos evidentes, dispostas de forma frouxa, formando vacúolos e microcistos. À imuno-histoquímica, o meningioma apresentou marcação fortemente positiva para citoqueratina e negativa para vimentina. Por meio da histopatologia e da imuno-histoquímica, foi possível estabelecer a classificação histológica de meningioma microcístico, bem como diferenciá-lo de outras doenças que cursam com sinais nervosos.(AU)

Meningiomas are the main tumors of the central nervous system (CNS) affecting dogs and cats. In most of the cases they are benign neoplasms, usually expansive, causing compression of the CNS and rarely metastasize to other organs. We describe the occurrence of a microcystic meningioma with pulmonary metastasis in an 11 - year - old canine with clinical signs of staggering gait, head compression against objects, agitation, salivation and aggressiveness. At necropsy, well-defined, firm, granular-looking masses located in the parietal cortex and nuclei of the base were observed in the encephalon. Numerous micronodulations of similar appearance were observed in the lung. Histologically, nodules formed by spindle neoplastic cells with large, elongated nuclei and evident nuclei were loosely arranged, forming vacuoles and microcysts. Immunohistochemistry were strongly positive for cytokeratin and negative for vimentin. Through the histopathology and immunohistochemistry, it was possible to establish the histological classification of microcystic meningioma, as well as to differentiate from other diseases that present with nervous signals.(AU)

Primary nonlymphoid gastrointestinal neoplasms in dogs in Rio Grande do Sul / Neoplasmas gastrointestinais primários não linfoides em cães no Rio Grande do Sul

Gastrointestinal neoplasms (GIN) are uncommon in dogs, but they mainly show malignant behavior and poor prognosis. The types of GIN in dogs and their frequency, as well as their epidemiological and histopathological characteristics were analyzed through a retrospective study of biopsies from 24.711 dogs from 2005 to 2017. Additionally, histological sections of neoplasms were subjected to immunohistochemistry (IHC) using antibodies against pancytokeratin, vimentin, smooth muscle actin, c-Kit, S-100, CD31, CD79αcy, and neuron-specific enolase. Of the total samples from dogs analyzed, 88 corresponded to GIN. Neoplasms occurred more frequently in purebred dogs (64.8%, 57/88), males (53.4%, 47/88), with a median age of 10 years. The intestine was affected by 84.1% (74/88) of the cases. Of these, the large intestine was the most affected (67.6%, 50/74). Most of the neoplasms had malignant behavior (88.6%, 78/88). Regarding the classification of neoplasms, 46.6% (41/88) of the diagnoses corresponded to epithelial, 46.6% (41/88) were mesenchymal, 5.7% (5/88) were hematopoietic, and 1.1% (1/88) was neuroendocrine. The most frequently diagnosed neoplasms were papillary adenocarcinoma (19.3%, 17/88), leiomyosarcoma (17.0%, 15/88), gastrointestinal stromal tumors (GISTs) (12.5%, 11/88), and leiomyoma (5.0%, 8/88). Adenocarcinomas were located mainly in the rectum, whereas leiomyosarcomas and GISTs developed mainly in the cecum. Epithelial neoplasms showed a greater potential for lymphatic invasion whereas mesenchymal neoplasms appeared to be more expansive with intratumoral necrosis and hemorrhage. Immunohistochemistry was found to be an important diagnostic technique for the identification of infiltrating cells in carcinomas and an indispensable technique for the definitive diagnosis of sarcomas.(AU)

Neoplasmas gastrointestinais (NGI) são pouco comuns em cães, mas possuem principalmente comportamento maligno e prognóstico reservado. Os tipos de NGI em cães e sua frequência, bem como características epidemiológicas e histopatológicas foram analisados por meio de um estudo retrospectivo dos exames de biópsias de 24.711 cães entre os anos de 2005 a 2017. Adicionalmente, cortes histológicos de NGI foram submetidos à técnica de imuno-histoquímica (IHQ), utilizando os anticorpos anti-pancitoqueratina, vimentina, actina de músculo liso, c-Kit, S-100, CD31, CD79αcy e enolase neurônio específica. Do total de cães analisados, 88 corresponderam a NGI não linfoides. Os neoplasmas ocorreram com maior frequência em cães de raça pura (64,8%, 57/88), machos (53,4%, 47/88), com mediana de idade de 10 anos. O intestino foi acometido em 84,1% dos casos (74/88). Destes, o intestino grosso foi o segmento mais afetado (67,6%, 50/74). A maior parte dos neoplasmas tinha comportamento maligno (88,6%, 78/88). Quanto à classificação, 46,6% (41/88) dos diagnósticos corresponderam a neoplasmas epiteliais, 46,6% (41/88) mesenquimais, 5,7% (5/88) hematopoiéticos e 1,1% (1/88), neuroendócrino. Os neoplasmas mais frequentemente diagnosticados foram adenocarcinoma papilar (19,3%, 17/88), leiomiossarcoma (17,0%, 15/88), tumor estromal gastrointestinal (GIST) (12,5%, 11/88) e leiomioma (12,5%, 8/88). Adenocarcinomas localizavam-se principalmente no reto, enquanto leiomiossarcoma e GISTs desenvolveram-se principalmente no ceco. Os neoplasmas epiteliais demonstraram um potencial maior de invasão linfática enquanto que os mesenquimais aparentaram ser mais expansivos, com necrose e hemorragia intratumorais. A imuno-histoquímica mostrou ser uma técnica diagnóstica importante para a identificação de células neoplásicas infiltravas no caso dos carcinomas e uma técnica indispensável para o diagnóstico definitivo de sarcomas.(AU)

Meningioma microcístico com metástase pulmonar em canino: relato de caso / Microcystic meningioma with pulmonary metastasis in canine: case report

Meningiomas são os principais tumores primários do sistema nervoso central (SNC) que afetam cães e gatos. Na maioria dos casos, são neoplasias benignas, geralmente expansivas, causando compressão do SNC, e raramente fazem metástase para outros órgãos. O presente trabalho tem como objetivo relatar a ocorrência de um meningioma microcístico com metástase pulmonar em um canino de 11 anos de idade, com sinais clínicos de andar cambaleante, compressão da cabeça contra objetos, agitação, salivação e agressividade. Na necropsia, foram observadas, no encéfalo, massas bem delimitadas pardo-avermelhadas, firmes, de aspecto granular, localizadas no córtex parietal e nos núcleos da base. Inúmeras micronodulações de aspecto semelhante foram observadas no pulmão. Histologicamente observaram-se nódulos formados por células neoplásicas fusiformes, com núcleos grandes e alongados e nucléolos evidentes, dispostas de forma frouxa, formando vacúolos e microcistos. À imuno-histoquímica, o meningioma apresentou marcação fortemente positiva para citoqueratina e negativa para vimentina. Por meio da histopatologia e da imuno-histoquímica, foi possível estabelecer a classificação histológica de meningioma microcístico, bem como diferenciá-lo de outras doenças que cursam com sinais nervosos.(AU)

Meningiomas are the main tumors of the central nervous system (CNS) affecting dogs and cats. In most of the cases they are benign neoplasms, usually expansive, causing compression of the CNS and rarely metastasize to other organs. We describe the occurrence of a microcystic meningioma with pulmonary metastasis in an 11 - year - old canine with clinical signs of staggering gait, head compression against objects, agitation, salivation and aggressiveness. At necropsy, well-defined, firm, granular-looking masses located in the parietal cortex and nuclei of the base were observed in the encephalon. Numerous micronodulations of similar appearance were observed in the lung. Histologically, nodules formed by spindle neoplastic cells with large, elongated nuclei and evident nuclei were loosely arranged, forming vacuoles and microcysts. Immunohistochemistry were strongly positive for cytokeratin and negative for vimentin. Through the histopathology and immunohistochemistry, it was possible to establish the histological classification of microcystic meningioma, as well as to differentiate from other diseases that present with nervous signals.(AU)

Leiomyosarcoma in a cockatiel / Leiomiossarcoma em calopsita

Cockatiels (Nymphicus hollandicus) are exotic birds thatoriginated from Australia.Because of their beauty and learning ability, they are one of the most popular pet birds among the Psittaciformes. The objective of this study was to report a case of leiomyosarcoma on the humeral musculature of the left wing of a cockatiel (Nymphicus hollandicus). The animal was admitted to the Wildlife Rehabilitation Center (NURFS-CETAS) of the Universidade Federal de Pelotas withswelling in the humeral region of the left wing. During surgery, the animal died and was transferred to the Laboratório Regional de Diagnóstico, Faculdade de Veterinária (LRD-UFPel). During histopathological evaluation (hematoxylin and eosin routine technique) of the tumor, spindle neoplastic cells were observed, arranged in interlaced bundles amongst degenerate and normal muscle fibers. Using immunohistochemistry, neoplastic cells were positively immunostained for vimentin and alpha smooth muscle actin. Based on of clinical-pathological and immunohistochemical findings, leiomyosarcoma was diagnosed.(AU)

As calopsitas (Nymphicus hollandicus) são aves exóticas originárias da Austrália. Devido a beleza e capacidade de aprendizado são uma das principais aves utilizadas como animal de companhia. O objetivo deste trabalho foi relatar um caso de leiomiossarcoma, na musculatura umeral da asa esquerda de uma calopsita. O animal deu entrada no Núcleo de Reabilitação da Fauna Silvestre (NURFS-CETAS) da Universidade Federal de Pelotas (UFPel), por apresentar aumento de volume na região umeral da asa esquerda. Durante o procedimento cirúrgico o animal veio a óbito, sendo encaminhado ao Laboratório Regional de Diagnóstico, Faculdade de Veterinária (LRD-UFPel). Na avaliação histopatológica (Técnica de rotina Hematoxilina e Eosina) da massa tumoral foram observadas células neoplásicas fusiformes, arranjadas em feixes entrelaçados, em meio a fibras musculares degeneradas e normais. Na imunohistoquímica verificou-se imunomarcação positiva das células neoplásicas para vimentina e alfa actina, de músculo liso. Diante dos achados clínico-patológicos e imunohistoquímicos determinou-se o diagnóstico de leiomiossarcoma. O diagnóstico definitivo deste neoplasma requer analise imunohistoquímica.(AU)

Caracterização anatomopatológica e imuno-histoquímica dos tumores das glândulas cutâneas em cães / Anatomopathological and immunohistochemical characterization of skin gland tumors in dogs

O presente estudo objetivou caracterizar os aspectos anatomopatológicos e imuno-histoquímicos dos tumores das glândulas cutâneas em cães. A caracterização morfológica seguiu a classificação atualizada da Organização Mundial de Saúde. Para a caracterização imuno-histoquímica, utilizaram-se anticorpos monoclonais primários anti-citoqueratina 14 (CK14), vimentina, p63, calponina, EGFR e Ki-67. Dos animais examinados, 66,67% (18/27) eram machos e 33,33% (9/27) fêmeas, 21 tinham raça definida e seis eram sem raça definida (SRD), com idade variando entre sete e 15 anos. Dos tumores caracterizados, 40,74% eram hepatoides (11/27), 29,63% sebáceos (8/27), 25,92% apócrinos (7/27) e 3,70% meibômio (1/27). Os tumores malignos representaram 55,56%, e os benignos 44,44%. Com esses resultados, foi possível demonstrar que os tumores das glândulas cutâneas em cães são frequentes, sem predileção por raça, sexo e com idade superior ou igual a sete anos. Os anticorpos CK 14, p63, vimentina e EGFR foram imunoexpressos nas células basais, células de diferenciação sebácea dos tumores hepatoides e de meibômio e células mioepiteliais. Entretanto, a vimentina e o EGFR não demonstraram imunomarcação para os tumores sebáceos. A calponina foi um bom marcador para as células mioepiteliais. O índice de Ki-67 foi mais acentuado nos tumores malignos em relação aos benignos. No entanto, estudos futuros utilizando maior número de casos se fazem necessários.(AU)

The present study aimed to characterize the anatomopathological and immunohistochemical aspects of cutaneous glandular tumors in dogs. Tumours were diagnosed according to the WHO criteria for canine skin neoplasms. For the immunohistochemical characterization, the primary monoclonal antibodies anti-cytokeratin 14 (CK14), vimentin, p63, calponin, EGFR and Ki-67 were used. Males were 66.67% (18/27) and females 33.33% (9/27), 21 had a defined race and 6 were mixed breed, with ages varying from 7 to 15 years. The tumors characterized were 40.74% hepatoid (11/27), 29.63% sebaceous (8/27), 25.92% apocrine (7/27) and 3.70% Meibômio (1/27). Malignant tumors accounted for 55.56% and benign tumors 44.44%. With these results it was possible to demonstrate that tumors of cutaneous glands in dogs are frequent, with no predilection for race, sex and with an age ≥ seven years. The CK 14 antibodies, p63, vimentin, and EGFR were imunoexpressed in the basal cells of the sebaceous cell differentiation and Meibomian hepatoides tumors and myoepithelial to cells. However, vimentin and EGFR did not demonstrate immunostaining for sebaceous tumors. Calponin was a good marker for myoepithelial cells. The Ki-67 index was more pronounced in malignant tumors compared to benign tumors. However, more studies are needed mainly using a higher number of tumors.(AU)

Caracterização anatomopatológica e imuno-histoquímica dos tumores das glândulas cutâneas em cães / Anatomopathological and immunohistochemical characterization of skin gland tumors in dogs

O presente estudo objetivou caracterizar os aspectos anatomopatológicos e imuno-histoquímicos dos tumores das glândulas cutâneas em cães. A caracterização morfológica seguiu a classificação atualizada da Organização Mundial de Saúde. Para a caracterização imuno-histoquímica, utilizaram-se anticorpos monoclonais primários anti-citoqueratina 14 (CK14), vimentina, p63, calponina, EGFR e Ki-67. Dos animais examinados, 66,67% (18/27) eram machos e 33,33% (9/27) fêmeas, 21 tinham raça definida e seis eram sem raça definida (SRD), com idade variando entre sete e 15 anos. Dos tumores caracterizados, 40,74% eram hepatoides (11/27), 29,63% sebáceos (8/27), 25,92% apócrinos (7/27) e 3,70% meibômio (1/27). Os tumores malignos representaram 55,56%, e os benignos 44,44%. Com esses resultados, foi possível demonstrar que os tumores das glândulas cutâneas em cães são frequentes, sem predileção por raça, sexo e com idade superior ou igual a sete anos. Os anticorpos CK 14, p63, vimentina e EGFR foram imunoexpressos nas células basais, células de diferenciação sebácea dos tumores hepatoides e de meibômio e células mioepiteliais. Entretanto, a vimentina e o EGFR não demonstraram imunomarcação para os tumores sebáceos. A calponina foi um bom marcador para as células mioepiteliais. O índice de Ki-67 foi mais acentuado nos tumores malignos em relação aos benignos. No entanto, estudos futuros utilizando maior número de casos se fazem necessários.(AU)

The present study aimed to characterize the anatomopathological and immunohistochemical aspects of cutaneous glandular tumors in dogs. Tumours were diagnosed according to the WHO criteria for canine skin neoplasms. For the immunohistochemical characterization, the primary monoclonal antibodies anti-cytokeratin 14 (CK14), vimentin, p63, calponin, EGFR and Ki-67 were used. Males were 66.67% (18/27) and females 33.33% (9/27), 21 had a defined race and 6 were mixed breed, with ages varying from 7 to 15 years. The tumors characterized were 40.74% hepatoid (11/27), 29.63% sebaceous (8/27), 25.92% apocrine (7/27) and 3.70% Meibômio (1/27). Malignant tumors accounted for 55.56% and benign tumors 44.44%. With these results it was possible to demonstrate that tumors of cutaneous glands in dogs are frequent, with no predilection for race, sex and with an age ≥ seven years. The CK 14 antibodies, p63, vimentin, and EGFR were imunoexpressed in the basal cells of the sebaceous cell differentiation and Meibomian hepatoides tumors and myoepithelial to cells. However, vimentin and EGFR did not demonstrate immunostaining for sebaceous tumors. Calponin was a good marker for myoepithelial cells. The Ki-67 index was more pronounced in malignant tumors compared to benign tumors. However, more studies are needed mainly using a higher number of tumors.(AU)

Fatal hemothorax caused by pleural mesothelioma in a lion / Hemotórax fatal causado por mesotelioma pleural em um leão

Mesothelioma is considered a malignant neoplasm caused by the proliferation of mesothelial cells mostly from the pleura, peritoneum and pericardium. Here we described a case of fatal hemothorax caused by pleural mesothelioma in a lion by means of necropsy, histopathology and immunohistochemistry. Gross inspection of the thoracic cavity showed hemothorax with about 4 liters of blood. Microscopically, numerous, randomly distributed, soft, red-pink, irregular masses with up to 1cm in diameter were observed in both visceral and parietal pleurae. Microscopically, a papillary structure pattern was observed in the thoracic masses, composed mainly by one layer of cubic mesothelial cells, which presented eosinophilic cytoplasm, central nucleus and evident nucleolus, supported by a low cellular fibrovascularstroma. Neoplastic cells were positive for both cytokeratin and vimentin by immunohistochemistry. This seems to be the first report of fatal hemothorax caused by pleural mesothelioma in a lion.(AU)

O mesotelioma é considerado um neoplasma maligna causada pela proliferação de células mesoteliais, principalmente da pleura, peritôneo e pericárdio. O presente caso descreve os achados macroscópicos, microscópicos e imuno-histoquímicos do hemotórax fatal causado por um mesotelioma pleural em um leão. Macroscopicamente, na cavidade torácica, foi observado cerca de 4 litros de sangue. Além disso, foram observadas numerosas massas macias, vermelho-rosa, irregulares, com até 1cm de diâmetro e distribuídas aleatoriamente pelas pleuras parietal e visceral. Microscopicamente, as massas torácicas apresentavam estruturas papilares, compostas por uma camada de células mesoteliais, que apresentavam citoplasma eosinofílico, núcleo central e nucléolo evidente, suportada por um estroma fibrovascular pouco celular. A imuno-histoquímica foi positiva para ambas citoqueratina e vimentina nas células neoplásicas. Este trabalho descreve o que parece ser o primeiro relato de um hemotórax fatal causado por um mesotelioma pleural em um leão.(AU)

Fatal hemothorax caused by pleural mesothelioma in a lion / Hemotórax fatal causado por mesotelioma pleural em um leão

Mesothelioma is considered a malignant neoplasm caused by the proliferation of mesothelial cells mostly from the pleura, peritoneum and pericardium. Here we described a case of fatal hemothorax caused by pleural mesothelioma in a lion by means of necropsy, histopathology and immunohistochemistry. Gross inspection of the thoracic cavity showed hemothorax with about 4 liters of blood. Microscopically, numerous, randomly distributed, soft, red-pink, irregular masses with up to 1cm in diameter were observed in both visceral and parietal pleurae. Microscopically, a papillary structure pattern was observed in the thoracic masses, composed mainly by one layer of cubic mesothelial cells, which presented eosinophilic cytoplasm, central nucleus and evident nucleolus, supported by a low cellular fibrovascularstroma. Neoplastic cells were positive for both cytokeratin and vimentin by immunohistochemistry. This seems to be the first report of fatal hemothorax caused by pleural mesothelioma in a lion.(AU)

O mesotelioma é considerado um neoplasma maligna causada pela proliferação de células mesoteliais, principalmente da pleura, peritôneo e pericárdio. O presente caso descreve os achados macroscópicos, microscópicos e imuno-histoquímicos do hemotórax fatal causado por um mesotelioma pleural em um leão. Macroscopicamente, na cavidade torácica, foi observado cerca de 4 litros de sangue. Além disso, foram observadas numerosas massas macias, vermelho-rosa, irregulares, com até 1cm de diâmetro e distribuídas aleatoriamente pelas pleuras parietal e visceral. Microscopicamente, as massas torácicas apresentavam estruturas papilares, compostas por uma camada de células mesoteliais, que apresentavam citoplasma eosinofílico, núcleo central e nucléolo evidente, suportada por um estroma fibrovascular pouco celular. A imuno-histoquímica foi positiva para ambas citoqueratina e vimentina nas células neoplásicas. Este trabalho descreve o que parece ser o primeiro relato de um hemotórax fatal causado por um mesotelioma pleural em um leão.(AU)