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)

Malignant tumor of peripheral nerve sheath in the thoracolumbar region in a cat

Background: In veterinary medicine, peripheral nerve tumors (PNST) are classified from the cellular pattern and as benign and malignant (MPNST). The majorities of cases are benign and usually involve the skin and subcutaneous tissue of the head, neck, and limbs. Animals with MPTNS usually have spinal cord and spinal canal involvement and are also described in the small and large intestine, oral cavity, perirenal region, and urinary bladder. Treatment is performed according to the location of the neoplasm and metastasis is rarely described. The present article aims to report a case of a malignant tumor in the peripheral nerve sheath of a cat. Case: A 8-year-old domestic cat was presented with a history of progressive paresis in the pelvic limbs. On neurological evaluation, proprioceptive ataxia and proprioception deficit in the pelvic limbs were observed, suggestive of thoracolumbar injury. Blood work and serum biochemistry showed results within the reference for the species and the bi-directional immunochromatography test for FIV and FeLV were negative. The radiographs of the thoracolumbar segment did not show significant changes. Myelography with iodinated contrast and collection of cerebrospinal fluid (CSF) were performed. On myelography examination, iodinated contrast loss was found between the 6th and 7th thoracic vertebrae, while the CSF analysis was normal. The patient underwent laminectomy and durotomy for excision of a mass found dorsally to the spinal cord, with intradural location. The tumor was sent for histopathological examination. Microscopic analysis showed neoplastic proliferation of spindle-shaped cells with predominance of the Antoni A pattern. Immunohistochemical analysis demonstrated intense cytoplasmic staining of the neoplastic cells for vimentin and S100 protein. Based on these findings, the diagnosis of malignant peripheral nerve sheath tumor was made. Radiotherapy was suggested as adjuvant treatment after surgical procedure. However, the owner refuse to follow this recommendation due to cost restriction. The patient had a satisfactory clinical recovery, he has no longer presented proprioceptive ataxia or proprioception deficits in three months after the surgical procedure. Discussion: In the case described, the feline patient presented a history, clinical signs, and findings in the myelography exam related to MPNST in the region of the vertebral canal. This neoplasm usually involves the spinal canal or spinal cord, but has been described in other locations, such in the small and large intestine, oral cavity, perirenal region, and urinary bladder. Based on the findings of the physical examination and complementary exams, a surgical procedure was recommended. Then, laminectomy and dutoromy were performed to remove the mass. The treatment described in the literature in cases of MPTNS is surgery, which can be curative, but in some cases, the use of radiotherapy may be necessary. The histological patterns observed in this neoplasm are the Antoni A and B, in the case described the Antoni A pattern was observed. The definitive diagnosis was made by immunohistochemistry with vimentin and S100 protein. MPNST are few described in the thoracolumbar region in cats. The surgical treatment was curative, where improvement of the clinical signs could be observed three months after surgery. In addition, monitoring of patients is recommended to ascertain relapses and metastases.

Metastatic gallbladder adenocarcinoma in a cat

Biliary neoplasms are uncommon in cats and affect older animals. A 12-year-old female crossbreed cat showed prostration, lethargy, apathy, and severe jaundice. Ultrasonography showed distention of the gallbladder associated with severe obstruction of the bile ducts with thickening of the biliary wall, forming amorphous masses of irregular contour and heterogeneous appearance directed to the lumen measuring up to 2 cm. Necropsy showed a gallbladder with a yellowish and soft nodule measuring 3 × 3 cm, compressing the extrahepatic bile duct, occluding the passage of bile. There were also firm, yellowish multifocal to coalescing nodules in the liver, ranging from 0.5 to 1 cm, affecting 10% of the organ, in addition to lungs with firm, yellowish multifocal nodules ranging from 0.2 to 0.5 cm, affecting 20% of the organ. Histologically, gallbladder and bile ducts had malignant epithelial neoplastic proliferation, which was organized into multiple papillary and ductal projections, separated by moderate fibrovascular stroma compatible with gallbladder adenocarcinoma. The liver and lungs also contained neoplastic structures with a ductal appearance and papilliform projections identical to those observed in the gallbladder. The immunohistochemical examination (IHC) showed intense positive staining of epithelial neoplastic cells for pan-cytokeratin (AE1/AE3) and no staining for vimentin (Clone V9). The diagnosis of gallbladder adenocarcinoma with metastasis in the liver and lungs was established based on the clinical, macroscopic, histopathological, and immunohistochemical findings.(AU)

Primary non-metastatic omental myofibrosarcoma in a horse / Miofibrossarcoma omental primário não metastático em um cavalo

Myofibrosarcoma in horses is a rare malignant tumor composed predominantly by myofibroblasts. A 15-year-old horse was referred to the Veterinary Hospital of the Federal University of Parana for evaluation of colic signs. Initial physical examination showed icteric mucous membrane and laboratory analysis found anemia, increased serum activity of ALT, GGT, ALP, and bilirubin. In the exploratory laparotomy a highly vascularized abdominal mass in the left hypochondrium region of approximately 50cm x 45cm x 30cm, adhered to the surrounding structures was observed. Due to the size and adhesions to the omentum, the mass was considered surgically unresectable, and euthanasia was performed followed by necropsy. The immunohistochemical and morphological results indicate the diagnosis of myofibrosarcoma since the neoplastic cells immunoexpressed Vimentin, HHF35 and S100. To the authors' knowledge, this is the first equine case of omental myofibrosarcoma described in the literature.

O miofibrossarcoma em cavalos é um raro tumor maligno, composto predominantemente por miofibroblastos. Um equino, de 15 anos de idade, foi encaminhado ao Hospital Veterinário da Universidade Federal do Paraná, para avaliação de sinais de cólica. O exame clínico inicial apresentou mucosas ictéricas e, nos exames laboratoriais, revelou anemia e aumento sérico de ALT, GGT, ALP e bilirrubina. Na laparotomia exploratória, observou-se massa abdominal vascularizada de aproximadamente 50cm x 45cm x 30cm na região do hipocôndrio esquerdo e aderida às estruturas circunvizinhas. Devido ao tamanho e às aderências ao omento, a massa foi considerada irressecável cirurgicamente, portanto foi realizada a eutanásia e a necropsia. Os resultados imuno-histoquímicos e morfológicos indicam o diagnóstico de miofibrossarcoma, visto que as células neoplásicas imunoexpressaram Vimentin, HHF35 e S100. Portanto, esse é o primeiro caso em equinos de miofibrossarcoma omental descrito na literatura.

Solid iridociliary carcinoma in a dog

Background: Iridociliary epithelial tumors (ICETs) originate from the iris epithelium or ciliary body. They comprise ciliary body adenoma, carcinoma, pleomorphic adenocarcinomas, medulloepitheliomas, and other primitive neuroectodermal tumors. They are the second most common primary intraocular tumors in dogs and have already been reported in sheep and humans. In dogs, they occur more frequently in middle-aged to elderly animals, and the Labrador and Golden Retriever seem to be more predisposed breeds. This study aimed to describe the clinical and pathological aspects of solid iridociliary carcinoma in a dog. Case: A 3-year-old Poodle bitch was treated for discomfort in the left eyeball region, increased intraocular pressure and moderate buphthalmia. A direct ophthalmological examination was performed without equipment, and a mass was visualized in the posterior chamber, distorting the pupillary cleft. We opted for unilateral enucleation and forwarded the material for histological analysis. Macroscopically, the eyeball measured 3.4 cm (anteroposterior) x 2.6 cm (vertical), with a brownish mass that occupied the entire anterior chamber and part of the posterior chamber. Histologically, there was a neoformation in the ciliary body and iris pigment epithelium, partially well-delimited and densely cellular. The neoplasm was organized into predominantly solid formations interspersed with a discrete amount of blood vessels, rare bundles of fibrous stroma, and amorphous eosinophilic material forming membranes that were positive for PAS. Sections of the neoplasm were subjected to immunohistochemistry using anti-cytokeratin AE1/AE3, anti-S100 protein, anti-vimentin, and anti-Ki-67. Positive cytoplasmic immunostaining for cytokeratin and S-100 was observed. Only 45.6% of cells were positive for Ki-67 (500 cells). No immunostaining was observed for vimentin. Discussion: The diagnosis of solid iridociliary carcinoma was based on the histological features and positive immunostaining for cytokeratin AE1/AE3 and protein S100. Iridociliary carcinomas present positive immunostaining for cytokeratin, whereas adenomas and normal iridociliary epithelium do not present this immunostaining. Moreover, the high rate of cell proliferation was indicative of malignant neoplasia, as observed by the high mitotic count and high positivity for Ki-67. The S100 protein helped in the diagnosis of ICETs, as the iridociliary epithelium showed positive staining for this protein. Some histological features are important to consider in the diagnosis of iridociliary tumors in dogs, such as noninvasive growth in the posterior chamber, pigment epithelium, and thick homogeneous membranes on the cell surface. Furthermore, the presence of positive PAS membranes favors the diagnosis of iridociliary epithelial tumors. ICETs must be differentiated from melanocytomas, anterior uveal melanoma, medulloepitheliomas, and metastatic and pleomorphic carcinomas. The histological characteristics, especially the presence of PAS-positive membranes, associated with the immunohistochemical profile of neoplasm cells, help differentiate the ICETs from these tumors. In general, the prognosis is poor for eyeball and vision maintenance in canine iridociliary tumors, and scleral invasion is associated with a higher recurrence rate.

Leiomiossarcoma metastático em ganso africano (Anser cygnoides) / Metastatic leiomyosarcoma in African goose (Anser cygnoides)

Background: In birds, neoplasms are more frequently observed in Psittaciformes and Galliformes and rarely seen in Columbiformes and Anseriformes, with few reports of the occurrence of mesenchymal neoplasms such as leiomyosarcoma affecting birds. Therefore, the objective of this study was to describe a case of metastatic leiomyosarcoma in an African goose (Anser cygnoides), analyzing the epidemiological, clinical and pathological aspects. Case: A 10-month-old male African goose, was referred to the Veterinary Hospital, Universidade Federal de Campina Grande, Patos, Paraiba, Brazil, whit ataxia, tremors of intention in the head, and nystagmus about one month ago, progressing to lateral decubitus. Due to the unfavorable prognosis, animal was euthanized. Samples of the organs of the coelomic cavity and central nervous system were collected for histologic examination. The samples were fixed in 10% buffered formalin. After fixation, the organs were embedded in paraffin, cut into 4-5 µm sections, and then stained with hematoxylin and eosin. Paraffin blocks with liver, kidney and encephalon fragments were selected and sent for immunohistochemical analysis. The primary antibodies used were: alpha-smooth muscle actin (monoclonal 1A4), anti-vimentin (monoclonal, V9), CD57 (monoclonal, NK1) and cytokeratin (monoclonal, AE1/AE3) and incubated for 18 h at 4Cº. As an amplification and detection system polymer and labeled by addition of the liquid diaminobenzidine+substratechromogen system and counterstained with Harris hematoxylin. Macroscopically were observed in the liver nodular multifocal areas yellowish, sometimes coalescing, firm, and elevated to the surface that at the cut deepened to the parenchyma. In the left kidney there was a similar tumor mass. In the left frontal lobe, there was nodular focal area, well circumscribed, yellowish and protruding. To cutting surface it compressed the parietal and temporal lobe and showed surface yellowish and smooth. Microscopically, the liver was diffusely infiltrated by mesenchymal neoplasia, expansive, infiltrative, poorly circumscribed and not encapsulated, constituted by spindle cells arranged in interlaced bundles. The cells were elongated with sparse cytoplasm, slightly eosinophilic and indistinct borders with rounded to elongated nuclei, with coarse chromatin and evident nucleoli. In fragments of kidney and brain, neoplastic infiltration similar to that described in the liver was observed. In immunohistochemistry, neoplastic cells were positive with antibodies anti-vimentin and alpha-smooth muscle actin. Discussion: The diagnosis of metastatic leiomyosarcoma in an African goose was based on epidemiological, clinical and pathological findings and confirmed by immunohistochemistry. Reports of neoplasms in birds are relatively rare, however the occurrence of metastatic leiomyosarcoma affecting goose in the most varied locations has been described, from skin to organs of the coelomic cavity like kidney, ovary and intestinal wall. In this case, there is the unusual occurrence of dissemination in the liver, kidney and cerebral cortex, progressing to a neurological clinic condition. There are rare cases of metastatic leiomyosarcoma in geese African goose (Anser cygnoides). The main differential diagnoses include fibrosarcomas, neurofibrosarcomas and histiocytic sarcomas, which are similar macroscopically and histologically.

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)

Sarcoma estromal esplênico em canino da raça labrador / Splenic stromal sarcoma in a labrador dog

Background: Splenic stromal neoplasms are a heterogeneous group of tumors that shares the morphology of spindle cells, and are considered a primary mesenchymal neoplasm of the spleen. Among these neoplasms, some are as yet unclassified. Although stromal neoplasms represent 25 a 50% of dog splenic neoplasms in dogs, subtypes rarely occur alone. As these neoplasms are difficult to diagnose in the routine veterinary medical examination, the objective of this article was to report a case of splenic stromal sarcoma in a dog treated at a private veterinary hospital in Recife, Pernambuco, Brazil. Case: An 8-year-old male labrador dog was treated at a veterinary hospital for an initial clinical suspicion of gastroenteritis. Clinical examinations showed anemic ocular mucosa and a distended abdomen. Considering the animal's condition, blood count, serum biochemistry, and abdominal ultrasonography (US) were requested. The laboratory tests revealed anemia, thrombocytopenia, leukocytosis with neutrophilia, and changes in the indices of alanine aminotransferase (ALT) and alkaline phosphatase (ALP), among other findings. Abdominal ultrasound showed hepatomegaly, diffuse splenomegaly, a neoformation in the spleen suggestive of splenic neoplasia, and mild cystic prostatic hyperplasia. The dog underwent exploratory laparotomy with splenectomy. During the procedure, a nodule was found attached to the spleen. It was removed, fixed in a 10% neutral buffered formalin solution, and sent for histopathological and immunohistochemical examinations (vimentin, S100, desmin, MyoD1, HHF35, CD31, and alpha smooth muscle actin). The histopathological diagnosis was poorly differentiated spindle cell splenic sarcoma, compatible with splenic stromal sarcoma. Immunohistochemistry showed neoplastic cells immunoreactive for vimentin and S100, and it was not reactive for other markers. Based on the immunohistochemical and morphological profile, the diagnosis of splenic stromal sarcoma was confirmed. Discussion: Dogs affected by splenic neoplasms are generally aged between three and 17 years, and clinically present with anorexia, emesis, lethargy, weight loss, and abdomen distension, which were observed in the present case. However, a purelyclinical diagnosis is disputable, since other diseases can present the same signs. Thus, complementary exams are essential for a correct diagnosis. Laboratory changes in blood count and serum biochemistry are considered nonspecific for splenic neoplasms, with neutrophilic leukocytosis and anemia being consistent with paraneoplastic syndromes frequently diagnosed in small animals. Microscopically, splenic stromal sarcomas are characterized by focal splenic nodules composed of cohesive polygonal to spindle-shaped cell layers. The cells usually exhibit anisokaryosis and often have large oval to round vesicular nuclei and, occasionally, multinucleated cells. They have large areas of necrosis, diffuse or nodular lymphoid aggregates, and foci of extramedullary hematopoiesis, consistent with the histopathological examination reported in the present case. The immunohistochemical analysis included evaluation of seven markers to elucidate the histogenesis of the neoplasm, with the anti-vimentin and anti-S100 markers demonstrating positive cytoplasmic immunoreactivity, revealing the mesenchymal origin of the neoplasm. Thus, the definitive diagnosis was splenic stromal sarcoma, a rare and aggressive neoplasm.

Non-functional neuroendocrine tumor with multisystemic metastasis in a cat

An eight-year-old castrated female feline was referred for necropsy with a history of apathy, inappetence, abdominal distension, hypersensitivity to abdominal palpation, and evidence of abdominal neoplasms on ultrasound. Macroscopically, multifocal to coalescent, yellowish-white, firm and infiltrative nodules were observed on the surface of the parietal peritonium and in abdominal and thoracic organs. Microscopic characteristics of the neoplasm suggested a neuroendocrine origin, but did not allow a definitive diagnosis and determination of the origin. Immunohistochemistry revealed that neoplastic cells expressed vimentin, CD56, neuron specific enolase, and PGP 9.5 and were negative for biogenic amines and hormonal peptides. Based on anatomopathological and immunohistochemical findings, diagnosis of metastatic non-functional neuroendocrine tumor was confirmed.(AU)

Non-functional neuroendocrine tumor with multisystemic metastasis in a cat

An eight-year-old castrated female feline was referred for necropsy with a history of apathy, inappetence, abdominal distension, hypersensitivity to abdominal palpation, and evidence of abdominal neoplasms on ultrasound. Macroscopically, multifocal to coalescent, yellowish-white, firm and infiltrative nodules were observed on the surface of the parietal peritonium and in abdominal and thoracic organs. Microscopic characteristics of the neoplasm suggested a neuroendocrine origin, but did not allow a definitive diagnosis and determination of the origin. Immunohistochemistry revealed that neoplastic cells expressed vimentin, CD56, neuron specific enolase, and PGP 9.5 and were negative for biogenic amines and hormonal peptides. Based on anatomopathological and immunohistochemical findings, diagnosis of metastatic non-functional neuroendocrine tumor was confirmed.

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)

Linfoma de células T na cavidade nasal de caprino / T-cell lymphoma in the nasal cavity in goat

Background: Lymphomas are considered uncommon in goats, being the multicentric form with the highest number of cases for the species. Primary intranasal lymphomas are often diagnosed in dogs, cats, and humans. In the literature, there is only a description of a multicentric case involving the frontal sinuses and mucosa of the nasal cavity in a goat; therefore, it is important to describe unusual cases of this disease for the inclusion of new clinical and pathological characteristics in the ruminant clinic medicine. The objective of this work is to describe a case of T-cell lymphoma in the nasal cavity of a young goat. Case: The animal had dyspnea and respiratory noise for 15 days. Clinical examination showed nodulation in the right nasal cavity associated with serosanguinous secretion. Tracheostomy was performed; however, after 30 days the animal was euthanized. A sagittal plane of the head showed a pinkish-gray mass in the right and left nasal cavity, with a smooth, multilobulated surface, smooth adhering to the rostral portion of the dorsal concha and occluding the dorsal nasal meatus. Submandibular lymph nodes were slightly enlarged. Histopathological examination of the nasal cavity revealed a non-encapsulated, poorly delimited and ulcerated tumor composed of round cells arranged in a mantle supported by a discrete fibrovascular stroma extending the mucosa and lamina propria. Cells were round with sparse, eosinophilic and poorly delimited cytoplasm. Nuclei varied from round to elongated with condensed chromatin and evident nucleoli. Occasionally, aberrant nuclei, reniform shape and multinucleated cells were seen. Pleomorphism was moderate characterized by anisocytosis and anisocariosis. Typical and atypical mitosis were frequent (0-4 per field of highest magnification [400x]). Amidst the neoplasm, there were multifocal areas of necrosis and hemorrhage associated with a mild lymphocytic inflammatory infiltrate. Immunohistochemistry showed positive immunostaining for Vimentin antibodies and CD3, and negative for pan CK and CD20. Discussion: The lymphomas immunophenotyping is little used when it comes to farm animals, and there are few studies that use this technique for the definitive diagnosis of these neoplasms for small ruminants. The use of this technique must be considered in each case, in order to determine the pathogenesis, the accurate diagnosis and the origin of the neoplastic lymphocytes. In goats, T-cell lymphomas are the most diagnosed, although cases of multicentric B-cell lymphomas with ocular involvement have been diagnosed. In view of the clinical picture of the case described, infectious rhinitis already described in goats, such as aspergillosis and protothecosis, should be included as differential diagnoses. However, the anatomopathological findings facilitate the direction of the diagnosis, since infectious rhinitis presents as nodules / ulcerated masses or focal areas of necrosis associated with purulent secretion and in the histopathological examination it is possible to observe the intralesional etiological agents. In addition, the enzootic ethmoidal tumor must be included, as it has similar clinical signs and affects young animals, but they are adenomas/adenocarcinomas that affect the ethmoidal nasal shells induced by a retrovirus. Lymphomas in the caprine species are rare in the Northeastern semi-arid, but that in the present diagnostic routine occasionally occurs, being important the first description of its nasal shape for its inclusion in the differential diagnoses of diseases that present with clinical obstruction and dyspnea for the species.

Tumor de células granulares pulmonar em um equino / Pulmonar granular cell tumor in a horse

Background: The occurrence of neoplasms in horses is relatively low. Granular cell tumor is a seldom diagnosed neoplasm, usually benign, of mesenchymal origin. Controversies exist regarding its origin, which is possibly from Schwann cells or cells with neuroendocrine differentiation. Despite being one of the main primary neoplasms in the lungs of horses, the number of cases is low in comparison to that of secondary lung tumors. Thus, this study proposes to report the anatomopathological aspects in a horse with granular cell tumor of primary pulmonary origin. Case: An 11-year-old female Quarter Horse breed underwent exploratory right lateral thoracotomy after presenting with chronic respiratory changes. During the operation, tumor masses were found in the right and left caudal pulmonary lobes. Due to the severity of clinical respiratory signs and the extent of the lesions, the animal was subjected to euthanasia and anatomopathological examination. Upon necroscopic examination, a tumor mass was found in the middle third of the left caudal lobe, rounded to flattened, measuring 10.0 × 8.0 cm in height and length, white in color, of firm consistency, smooth and regular surface and rising to the lung surface. When sectioned, the mass showed to be composed of multiple firm and dense circular lobes, separated by a thin layer of connective tissue. The tumor invaded the lumen of nearby segmental and subsegmental bronchi, which were partially or totally obstructed by the mass. In the right lung, multiple similar nodules were observed, accompanied by peritumoral hemorrhage. Histopathological analysis of the new formation revealed a dense cluster of cells that expanded over the lung parenchyma. The neoplastic cells were pleomorphic, moderately cohesive, without defined borders, with abundant cytoplasm, densely eosinophilic and finely granular. Intracytoplasmic granules were well evidenced by periodic acid Schiff staining (PAS). The cell nucleus was rounded to oval, excentric, markedly basophilic and with dense chromatin. There was moderate anisocytosis and mild anisokaryosis, with rare mitotic figures. Immunohistochemical analysis revealed positive staining for anti-vimentin and anti-S100 antibodies, confirming the diagnosis of granular cell tumor. Discussion: Granular cell tumors have no predisposition as to breed, sex or age. However, most of the described cases are reported in female horses aged around 13 years. The advanced age of the diagnosed animals may be related to late definitive diagnosis, since the clinical signs are nonspecific and treated palliatively like other respiratory diseases. Macroscopically, this tumor is more common in the multinodular form and, as observed in this case, it has a greater capacity for infiltration. Histologically, the visualization of large, polygonal cells, with a wide cytoplasm containing eosinophilic granules leads to the diagnosis of granular cell tumor. However, PAS staining and immunohistochemical tests were essential for the diagnostic conclusion in this report, confirming the presence of cytoplasmic granules and the mesenchymal and neuroectodermal origin of this neoplasm, respectively. Thus, considering the low occurrence of pulmonary granular cell tumor, the description of this case contributes to the basis of the knowledge of medical-veterinary professionals about this tumor in its clinical and diagnostic aspects.

Mediastinal extraskeletal osteosarcoma in a canine with pulmonary and cerebral metastasis

Background: Extraskeletal osteosarcoma (EOS), a rare variant of osteosarcoma (OS), is a malignant neoplasm that develops insoft tissues without primary bone involvement. This study aims to describe a case of EOS with a mediastinal location in a canine.Case: A 10-year-old male Uruguayan Cimarron dog, was presented to the Laboratório Regional de Diagnóstico, Faculdadede Veterinária, Universidade Federal de Pelotas (LRD/FV/UFPel) for necropsy. The dog had a history of submandibularswelling, progressive hind limb paralysis, muscle atrophy, and breathing difficulties. During necropsy, in the thoracic cavity,approximately 900 mL of serosanguinous exudate and a reddish-brown, bossed mediastinal mass measuring 15.0 cm in thelongest axis were also noted. The lung exhibited multifocal to coalescent, white, firm nodules extending from the pleurato the parenchyma and measuring up to 4.5 cm in diameter. In the parietal and occipital region of the brain, a matte winemass measuring 2.3 cm in the longest axis was observed. Fragments of the neoplastic mass, organs of the abdominal andthoracic cavities, and the brain were harvested and fixed in 10% buffered formalin. After 48 h, the samples were routinelyprocessed, incorporated in paraffin, cut into 3 µm-thick sections, and stained using Hematoxylin and Eosin (HE). Selectedsections of the neoplasm, the lung, and the brain were subjected to Von Kossa staining and immunohistochemical (IHC)analysis. For IHC, primary anti-cytokeratin monoclonal antibodies (clone AE1 / AE3, BioCare Medical) at a 1:100 dilution, vimentin (clone V9, BioCare Medical) at a 1:100 dilution, S100 Protein (clone 15E2E2, BioCare Medical) at a 1:100dilution, and Ki67 (SP6 clone, BioCare Medical) at a 1:50 dilution were used. Immunostaining ...

Mediastinal extraskeletal osteosarcoma in a canine with pulmonary and cerebral metastasis

Background: Extraskeletal osteosarcoma (EOS), a rare variant of osteosarcoma (OS), is a malignant neoplasm that develops insoft tissues without primary bone involvement. This study aims to describe a case of EOS with a mediastinal location in a canine.Case: A 10-year-old male Uruguayan Cimarron dog, was presented to the Laboratório Regional de Diagnóstico, Faculdadede Veterinária, Universidade Federal de Pelotas (LRD/FV/UFPel) for necropsy. The dog had a history of submandibularswelling, progressive hind limb paralysis, muscle atrophy, and breathing difficulties. During necropsy, in the thoracic cavity,approximately 900 mL of serosanguinous exudate and a reddish-brown, bossed mediastinal mass measuring 15.0 cm in thelongest axis were also noted. The lung exhibited multifocal to coalescent, white, firm nodules extending from the pleurato the parenchyma and measuring up to 4.5 cm in diameter. In the parietal and occipital region of the brain, a matte winemass measuring 2.3 cm in the longest axis was observed. Fragments of the neoplastic mass, organs of the abdominal andthoracic cavities, and the brain were harvested and fixed in 10% buffered formalin. After 48 h, the samples were routinelyprocessed, incorporated in paraffin, cut into 3 µm-thick sections, and stained using Hematoxylin and Eosin (HE). Selectedsections of the neoplasm, the lung, and the brain were subjected to Von Kossa staining and immunohistochemical (IHC)analysis. For IHC, primary anti-cytokeratin monoclonal antibodies (clone AE1 / AE3, BioCare Medical) at a 1:100 dilution, vimentin (clone V9, BioCare Medical) at a 1:100 dilution, S100 Protein (clone 15E2E2, BioCare Medical) at a 1:100dilution, and Ki67 (SP6 clone, BioCare Medical) at a 1:50 dilution were used. Immunostaining ...(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.