Cutaneous myxoma in broiler chicken detected during slaughtering

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

Carcinoma hepatocelular metastático em Amazona aestiva / Metastatic hepatocellular carcinoma in Amazona aestiva

Background: Hepatocellular carcinoma is a primary malignant tumor of the liver tissue and its occurrence in birds is considered rare. The tumor can occur as a single mass leading to hepatomegaly, or as multiple nodules in the liver. In animals of the genus Amazona, only 1 case of metastatic hepatocellular carcinoma has been reported in the United States, therefore, little is known about its epidemiology and clinicopathological aspects in these species. In this context, the aim of this work was to describe a case of metastatic hepatocellular carcinoma in an Amazona aestiva. Case: A blue-fronted amazon parrot (Amazona aestiva) was referred to necropsy after being found dead in its enclosure. On examination, it presented cachectic body score. Examination of the coelomic cavity, revealed a serous translucent fluid and adhesions between the liver and peritoneum.A red mass restricted to the right hepatic lobe and raised to the capsular surface, interspersed with whitish and dark red multifocal areas was observed. When cut, this mass was soft, protruding, multilobulated, whitish and with a friable reddish center. Additionally, on the dorsal surface of the left lung lobe, there was a rounded, well defined, whitish, and soft nodule. Microscopically, partial replacement of the hepatic parenchyma was observed by neoplastic proliferation of cuboidal epithelial cells, organized in mantle and supported by a scarce fibrovascular stroma. Cells have large, eosinophilic, well-delimited cytoplasm, with a central, oval nucleus, loose chromatin, and evident nucleolus. Moderate pleomorphism was characterized by anisocytosis, anisokaryosis, and aberrant nuclei. In the lung, a focally extensive mass with a pattern similar to that seen in the liver was observed. In the kidney, multifocal neoplastic emboli were noted. Liver immunohistochemistry was performed. Positive and negative controls were used to validate the reaction; however, there was no immunolabelling for the evaluated antibodies. Discussion: The histopathological characteristics observed in this study favored the diagnosis of hepatocellular carcinoma (HCC) with metastasis to kidney and lung. Primary liver tumors are rare in wild birds. In ducks, experimental studies have pointed aflatoxins and the duck hepatitis B virus as oncogenic agents, however, in birds of the genus Amazona, there are no studies that evaluate predisposing factors to the development of liver carcinoma. Macroscopically, hepatocellular carcinoma may present in massive, nodular or diffuse forms. In birds, the right lobe is the largest, which may suggest that this lobe is more prone to the development of HCC, as seen in the present case. The solid form, similar to that observed in this report, seems to be more commonly observed, as seen in the wild bird reports consulted. Metastases most often spread hematogenous, and in the present report there was metastasis to kidneys and lungs, which is a common feature for this neoplasm. In the present case, there was no labeling by any of the antibodies, perhaps because of their aggressiveness, associated with autolytic factors that prevent the labeling of antibodies, in addition to the specificity in the antibodyantigen relationship. This tumor must be differentiated from other liver tumors such as cholangiocarcinoma, and also the well-differentiated hepatocellular adenoma, in addition to non-neoplastic conditions. HCC should be considered as a differential diagnosis for Amazona aestiva found dead in the enclosure without previous clinical signs. This neoplasm is rare in Amazon parrots and reports should be encouraged in order to contribute to the understanding of the epidemiological and clinicopathological aspects of the tumor.

The Unicorn Mouse: Cranial Lipoma in a B6. Cg Mouse

Intracranial lipomas, also called intracranial lipomatous hamartomas, have been reported in some strains of research mice, but are rare in C57BL6 strains. It is presumed based on current publications that this is the first report of an intracranial lipoma in a mouse with this genetic change (B6.Cg-Cnpy2 tm1.2 Zhli Alb-Cre). Grossly, a fur-covered, soft, cylindrical, exophytic mass on the dorsal midline of the cranium was evident. Upon dissection, a soft, white, tubular structure extended through a 1mm defect in the sagittal suture of the skull to the deep surface of the hypodermis. Histologically, the mass consisted of well demarcated proliferation of mature white adipocytes, each containing one large fat droplet. The mass extended from the cerebrum at the level just caudal to the hippocampus in the third ventricle, between the superior colliculus and the caudal portion of the retrosplenial area and through the sagittal suture to the hypodermis and was surrounded by normal brain tissue.(AU)

Achados radiográficos e ultrassonográficos de fibrossarcoma em membro torácico de gatos: relato de três casos / Radiographic and ultrasound findings of fibrosarcoma in the cats: reports of three cases / Hallazgos radiográficos y ultrasonidos de fibrosarcoma en la extremidad torácica de gatos: informe de tres casos

O fibrossarcoma é uma neoplasia mesenquimal maligna originada dos fibroblastos que localiza-se especificamente em tecido cutâneo, subcutâneo e cavidade oral. A ressecção cirúrgica do tumor com margem de segurança é conhecida como a principal forma de tratamento. A principal forma de metástase é a via hematógena, atingindo pulmões, e menos comum em linfonodos regionais. A análise histopatológica é o exame diagnóstico de eleição para definição do tipo de tumor e sua graduação. Os exames de imagem são fundamentais no estadiamento das neoplasias e planejamento cirúrgico. A ultrassonografia e radiografia são os métodos mais utilizados e oferecem um grande apoio a oncologia médica veterinária. O exame radiográfico possibilita o achado de neoformações ósseas ou demais alterações como o aumento de volume de tecidos moles, infiltração gordurosa, e cavitações com gás ou fluído. O exame ultrassonográfico permite o conhecimento sobre a ecotextura, organização, e localização da lesão em tecidos moles. Em três gatos com fibrosssarcoma em membro torácico, foram realizadas radiografia e ultrassonografia específica da lesão. Os achados radiográficos foram aumento de volume, radiopacidade dos tecidos moles, sem acometimento ósseo. Os achados ultrassonográficos foram lesões de ecotextura grosseira, altamente heterogêneas. Os exames citológicos e histopatológicos revelaram tratar-se de fibrossarcoma. O presente relato tem como objetivo descrever os achados radiográficos e ultrassonográficos de fibrossarcoma em membro torácico de três gatos.

Fibrosarcoma is a malignant mesenchymal neoplasm originating from fibroblasts, which is specifically located in the skin tissue, subcutaneous tissue and oral cavity. Surgical resection of the tumor with a safety margin is known as the main form of treatment. The main form of metastasis is the hematogenous route, reaching the lungs, and less common in regional lymph nodes. histopathological analysis is the diagnostic test of choice for defining the type of tumor and its graduation. Imaging exams are essential in the staging of neoplasms and surgical planning. Ultrasonography and radiography are the most used methods and offer great support to veterinary medical oncology. The radiographic exam allows the finding of bone neoformations or other alterations such as the increase in soft tissue volume, fatty infiltration, and cavitations with gas or fluid. The ultrasound examination allows knowledge about the echotexture, organization, and location of the soft tissue lesion. Three cats with fibrosarcoma in the thoracic limb underwent lesion-specific radiography and ultrasound. The radiographic findings of fibrosarcomas were increased soft tissue radiopacity volume, without bone involvement. And the ultrasonographic findings were gross echotexture lesions, highly heterogeneous. Cytological and histopathological examinations were performed for definitive diagnosis. The present report aims to describe the radiographic and ultrasonographic findings of fibrosarcoma in the thoracic limb of three cats.

RESUMEN El fibrosarcoma es una neoplasia mesenquimatosa maligna que se origina a partir de fibroblastos, que se localiza específicamente en el tejido cutáneo, tejido subcutáneo y cavidad oral. La resección quirúrgica del tumor con un margen de seguridad se conoce como la forma principal de tratamiento. La principal forma de metástasis es la vía hematógena, que llega a los pulmones y es menos común en los ganglios linfáticos regionales. El análisis histopatológico es la prueba diagnóstica de elección para definir el tipo de tumor y su graduación. Los exámenes por imágenes son esenciales en la estadificación de las neoplasias y la planificación quirúrgica. La ecografía y la radiografía son los métodos más utilizados y ofrecen un gran apoyo a la oncología médica veterinaria. El examen radiográfico permite encontrar neoformaciones óseas u otras alteraciones como aumento de volumen de tejidos blandos, infiltración grasa y cavitaciones con gas o líquido. El examen ecográfico permite conocer la ecotextura, organización y ubicación de la lesión de tejidos blandos. A tres gatos con fibrosarcoma en la extremidad torácica se les realizó una radiografía y una ecografía específicas de la lesión. Los hallazgos radiográficos de los fibrosarcomas fueron un aumento del volumen de radiopacidad de los tejidos blandos, sin afectación ósea. Y los hallazgos ecográficos fueron lesiones macroscópicas de ecotextura, muy heterogéneas. Se realizaron exámenes citológicos e histopatológicos para el diagnóstico definitivo. El presente informe tiene como objetivo describir los hallazgos radiográficos y ecográficos del fibrosarcoma en la extremidad torácica de tres gatos.

Chemodectoma in a bitch

Background: Chemodectomas, better known as tumors of the base of the heart, arise from aortic bodies, respiratory chemoreceptors located near or inside the aortic arch or originate from receptors located in the carotid arteries. Relatively rare, they affect dogs and, to a lesser extent, cats. They gain great importance when they influence the function of the cardiovascular system, with animals showing clinical signs related to congestive heart failure. Clinical diagnosis is based on symptomatology and complementary tests such as radiography, electrocardiography and echocardiography, while the definitive diagnosis is obtained by cytological and histopathological exams. This study aims to reports a case of malignant chemodectoma in a bitch, whose main symptomatology was neurological and not cardiovascular. Case: A 1-year-old Rottweiler bitch was attended with neurological alterations compatible with vestibular syndrome, hyporexia, dysphagia, apathy, melena, emesis, and purulent nasal discharge on the right nostril. On physical examination, the animal showed depressed level of consciousness, poor body condition, bilateral quemosis, paralysis of the right eye, inspiratory dyspnea and muffling of cardiac auscultation, besides a subcutaneous nodule between the scapulae. On neurological evaluation, horizontal nystagmus, head tilt to the right side, ventromedial strabismus and facial nerve paralysis on the right side were observed so that the localization of the lesion was set in peripheral vestibular system. During anesthesia for esophageal tube placement, a mass from the hard palate to the oropharynx was noted, making endotracheal intubation impossible to perform. Biopsy of this nodule was performed, and tracheostomy was indicated, but the owner opted for euthanasia before the procedure. Necropsy revealed white soft masses in the bilateral retromandibular region, on the subcutaneous tissue near the scapulae, in the right ear and since nasopharynx to the soft palate, in addition to sparse white nodules in the heart, lung, carotid artery, kidneys, right ovary, mesentery near to the spleen, and axillary lymph node. Histologically, the nodules were characterized by neoplastic cells population organized in short bundles or cords, arranged around small blood vessels surrounded by delicate connective tissue. Neoplastic cells infiltrated muscles and blood and lymphatic vessels were filled by multiple neoplastic emboli. The histological pattern of the cells allowed the diagnosis of chemodectoma. Discussion: The bitch from this case had 1-year-old when diagnosed with chemodectoma, differently from most cases from literature, that are between 7 to 15 years old. Furthermore, primarily cardiac tumors are considered rare, being chemodectoma the most common, often reported in Boxer and Boston Terrier dogs, but unusual in Rottweilers. Despites some articles mentioning seizure and Horner's Syndrome secondary to a carotid body chemodectoma, neurological signs are not commonly observed in these cases. The presence of the tumor in the middle ear region of the right side supports the occurrence of peripheral vestibular syndrome and facial nerve paralysis on the same side. Because it is a neoplasm that is usually detected late during the course of the disorder, most patients either cannot obtain diagnosis in vivo, as in this reported animal, which was in such a critical condition that underwent euthanasia, or there are no more possible therapeutic choices. In the patient described, there were numerous metastatic masses and nodules spread throughout the body. Although the typical clinical signs in animals with chemodectomas are often related to heart disease, neurological signs may also be present. This report emphasizes the importance of chemodectoma being included as a differential diagnosis in young dogs and even in breeds such as Rottweiler.

Correlation of Clinical, Histopathological and Histomorphometric Features of Canine Soft Tissue Sarcomas

Sarcomas de partes moles (STS) representam um grupo heterogêneo de tumores com características histológicas e comportamento biológico semelhantes. Este estudo teve como objetivo descrever a correlação entre as características clínicas, histopatológicas e histomorfométricas do STS em cães. Os registros médicos foram revisados ​​para identificar todos os cães nos quais um STS foi diagnosticado entre 2006-2017. Trinta casos foram incluídos, e amostras de tumor e prontuários médicos foram recuperados. A maioria dos cães era mestiça (40%) e 80% dos STS localizavam-se no tecido conjuntivo subcutâneo. A classificação histopatológica mostrou que sarcoma indiferenciado (17%) e tumor de bainha de nervo periférico (30%) foram os STS mais comuns. O STS de grau I foi obtido em 50% dos casos (15/30), e os tumores de grau II ou III comprometeram 43% (13/30) e 7% (2/30), respectivamente. O índice mitótico variou de zero a 26 (5,8 ± 7,5). A razão núcleo: citoplasma aumentada foi moderadamente associada com maior grau de tumor (p = 0,05; rS = 0,361) e índice mitótico (p = 0,05; rS = 0,355), enquanto o número de microvasos foi positivamente correlacionado com o grau de diferenciação (p = 0,05 ; rS = 0,362) e pleomorfismo nuclear (p = 0,036; rS = 0,384). A histomorfometria mostrou-se útil na avaliação do STS, representando uma ferramenta adicional correlacionada a fatores prognósticos bem estabelecidos (grau histopatológico, grau de diferenciação, pleomorfismo nuclear). enquanto o número de microvasos foi positivamente correlacionado com o grau de diferenciação (p = 0,05; rS = 0,362) e pleomorfismo nuclear (p = 0,036; rS = 0,384). A histomorfometria mostrou-se útil na avaliação do STS, representando uma ferramenta adicional correlacionada a fatores prognósticos bem estabelecidos (grau histopatológico, grau de diferenciação, pleomorfismo nuclear). enquanto o número de microvasos foi positivamente correlacionado com o grau de diferenciação (p = 0,05; rS = 0,362) e pleomorfismo nuclear (p = 0,036; rS = 0,384). A histomorfometria mostrou-se útil na avaliação do STS, representando uma ferramenta adicional correlacionada a fatores prognósticos bem estabelecidos (grau histopatológico, grau de diferenciação, pleomorfismo nuclear).

Correlation of Clinical, Histopathological and Histomorphometric Features of Canine Soft Tissue Sarcomas

Sarcomas de partes moles (STS) representam um grupo heterogêneo de tumores com características histológicas e comportamento biológico semelhantes. Este estudo teve como objetivo descrever a correlação entre as características clínicas, histopatológicas e histomorfométricas do STS em cães. Os registros médicos foram revisados ​​para identificar todos os cães nos quais um STS foi diagnosticado entre 2006-2017. Trinta casos foram incluídos, e amostras de tumor e prontuários médicos foram recuperados. A maioria dos cães era mestiça (40%) e 80% dos STS localizavam-se no tecido conjuntivo subcutâneo. A classificação histopatológica mostrou que sarcoma indiferenciado (17%) e tumor de bainha de nervo periférico (30%) foram os STS mais comuns. O STS de grau I foi obtido em 50% dos casos (15/30), e os tumores de grau II ou III comprometeram 43% (13/30) e 7% (2/30), respectivamente. O índice mitótico variou de zero a 26 (5,8 ± 7,5). A razão núcleo: citoplasma aumentada foi moderadamente associada com maior grau de tumor (p = 0,05; rS = 0,361) e índice mitótico (p = 0,05; rS = 0,355), enquanto o número de microvasos foi positivamente correlacionado com o grau de diferenciação (p = 0,05 ; rS = 0,362) e pleomorfismo nuclear (p = 0,036; rS = 0,384). A histomorfometria mostrou-se útil na avaliação do STS, representando uma ferramenta adicional correlacionada a fatores prognósticos bem estabelecidos (grau histopatológico, grau de diferenciação, pleomorfismo nuclear). enquanto o número de microvasos foi positivamente correlacionado com o grau de diferenciação (p = 0,05; rS = 0,362) e pleomorfismo nuclear (p = 0,036; rS = 0,384). A histomorfometria mostrou-se útil na avaliação do STS, representando uma ferramenta adicional correlacionada a fatores prognósticos bem estabelecidos (grau histopatológico, grau de diferenciação, pleomorfismo nuclear). enquanto o número de microvasos foi positivamente correlacionado com o grau de diferenciação (p = 0,05; rS = 0,362) e pleomorfismo nuclear (p = 0,036; rS = 0,384). A histomorfometria mostrou-se útil na avaliação do STS, representando uma ferramenta adicional correlacionada a fatores prognósticos bem estabelecidos (grau histopatológico, grau de diferenciação, pleomorfismo nuclear).(AU)

Histomorphological and immunophenotypic characterizationof feline injection site-associated sarcoma

Background: Feline Injection Site-Associated Sarcoma (FISS) is a mesenchymal neoplasia of aggressive behavior thatdevelops in sites where vaccine or drugs were administered. FISS is clinically characterized by the appearance of asolitary firm nodule or a diffuse mass, adhered to tissues, in regions associated to vaccine or drug applications. Despitelow prevalence, tumor recurrence rates can reach 80%. FISS present more aggressive histological characteristics whencompared to sarcomas not associated to injection sites. The aim of this paper is to contribute towards the understandingof the biological behavior of FISS.Materials, Methods & Results: Sixteen samples of FISS were analyzed. Fibrosarcomas were the most frequent histological subtype (62.5%). Malignant peripheral nerve sheath tumor was diagnosed in 18.75% cases. Ten (62.5%) FISS wereclassified as grade II; 4/16 (25%) grade I, and 2/16 (12.5%) grade III. Cox-2 overexpression occurred in 3/16 (18.75%)samples, with positive correlation between Cox-2 expression and cellularity (r = 0.696, P = 0.003). Mitotic index lowerthan 9 events was found in 11/16 (68.7%) samples and between 10 and 19 mitotic events in 5/16 (31.3%) cases. MeanKi-67 expression was 2.39 ± 2.48%. FISS characterized as fibrosarcomas presented longer overall survival (median 545days) than other histological subtypes (median 130.5 days) [P = 0.01].Discussion: Patients with FISS generally present with larger nodules than those with sarcomas not associated to injections,suggesting a challenge for pet owners to note subcutaneous tumors in the interscapular region, in addition to the aggressivebiological behavior of FISS. The influence of size on prognosis remains controversial. An association between histologicgrade and the development of metastasis has been observed, with patients with grade III FISS associated with an increasein the metastatic rate. The present study did not find a correlation between overall survival...

Histomorphological and immunophenotypic characterizationof feline injection site-associated sarcoma

Background: Feline Injection Site-Associated Sarcoma (FISS) is a mesenchymal neoplasia of aggressive behavior thatdevelops in sites where vaccine or drugs were administered. FISS is clinically characterized by the appearance of asolitary firm nodule or a diffuse mass, adhered to tissues, in regions associated to vaccine or drug applications. Despitelow prevalence, tumor recurrence rates can reach 80%. FISS present more aggressive histological characteristics whencompared to sarcomas not associated to injection sites. The aim of this paper is to contribute towards the understandingof the biological behavior of FISS.Materials, Methods & Results: Sixteen samples of FISS were analyzed. Fibrosarcomas were the most frequent histological subtype (62.5%). Malignant peripheral nerve sheath tumor was diagnosed in 18.75% cases. Ten (62.5%) FISS wereclassified as grade II; 4/16 (25%) grade I, and 2/16 (12.5%) grade III. Cox-2 overexpression occurred in 3/16 (18.75%)samples, with positive correlation between Cox-2 expression and cellularity (r = 0.696, P = 0.003). Mitotic index lowerthan 9 events was found in 11/16 (68.7%) samples and between 10 and 19 mitotic events in 5/16 (31.3%) cases. MeanKi-67 expression was 2.39 ± 2.48%. FISS characterized as fibrosarcomas presented longer overall survival (median 545days) than other histological subtypes (median 130.5 days) [P = 0.01].Discussion: Patients with FISS generally present with larger nodules than those with sarcomas not associated to injections,suggesting a challenge for pet owners to note subcutaneous tumors in the interscapular region, in addition to the aggressivebiological behavior of FISS. The influence of size on prognosis remains controversial. An association between histologicgrade and the development of metastasis has been observed, with patients with grade III FISS associated with an increasein the metastatic rate. The present study did not find a correlation between overall survival...(AU)

Lipossarcoma pleomórfico esplênico primário em uma cadela / Primary splenic pleomorphic liposarcoma in a bitch

Background: Liposarcoma is a malignant neoplasm of lipoblasts with low incidence in dogs, representing 1.7% of tumorsdiagnosed in the spleen. In veterinary medicine, this neoplasm is classified morphologically into the myxoid, well-differentiated, undifferentiated and pleomorphic subtypes, the latter being one of the most aggressive forms, mainly in cavityorgans. This report refers to a primary splenic pleomorphic liposarcoma in a female dog, addressing anatomopathologicaland immunohistochemical aspects.Case: A 14-year-old, 35 kg bitch mongrel with history of absence of defecation, progressive weight loss, difficulty walking, sensitivity to abdominal palpation, prostration, pale mucous membranes, tachypnea and abdominal distention waspresented to diagnosis. The condition evolved to death and, on necroscopy, there was an increase in splenic volume withneoformation of whitish and reddish color, measuring 32 × 27 cm in its largest axes and weighing 8.9 kg. The neoformationexhibited areas of firm and soft consistency, and sectioning revealed focal areas of extensive necrosis and cavity collectionsof different diameters that allowed the flow of liquid serous contents with a brownish red color. Microscopy showed cellsof neoplastic morphology infiltrating the splenic parenchyma, mostly with slightly acidophilic cytoplasm and few intracytoplasmic lipid vacuoles, which varied in size and distribution. The nucleus of the cells was large, eccentric and irregular,with round to oval morphology, grossly lacy chromatin and single or multiple evident nucleoli. These cells exhibited markedanisocytosis, anisokaryosis and pleomorphism, with more than one mitotic figure per high magnification field visible. Mildinflammatory infiltrate, predominantly lymphocytic, permeated the neoplastic cells, and marked depletion of lymphoidfollicles and atrophy of the red pulp were found in the remaining splenic parenchyma. Immunohistochemical tests...

Lipossarcoma pleomórfico esplênico primário em uma cadela / Primary splenic pleomorphic liposarcoma in a bitch

Background: Liposarcoma is a malignant neoplasm of lipoblasts with low incidence in dogs, representing 1.7% of tumorsdiagnosed in the spleen. In veterinary medicine, this neoplasm is classified morphologically into the myxoid, well-differentiated, undifferentiated and pleomorphic subtypes, the latter being one of the most aggressive forms, mainly in cavityorgans. This report refers to a primary splenic pleomorphic liposarcoma in a female dog, addressing anatomopathologicaland immunohistochemical aspects.Case: A 14-year-old, 35 kg bitch mongrel with history of absence of defecation, progressive weight loss, difficulty walking, sensitivity to abdominal palpation, prostration, pale mucous membranes, tachypnea and abdominal distention waspresented to diagnosis. The condition evolved to death and, on necroscopy, there was an increase in splenic volume withneoformation of whitish and reddish color, measuring 32 × 27 cm in its largest axes and weighing 8.9 kg. The neoformationexhibited areas of firm and soft consistency, and sectioning revealed focal areas of extensive necrosis and cavity collectionsof different diameters that allowed the flow of liquid serous contents with a brownish red color. Microscopy showed cellsof neoplastic morphology infiltrating the splenic parenchyma, mostly with slightly acidophilic cytoplasm and few intracytoplasmic lipid vacuoles, which varied in size and distribution. The nucleus of the cells was large, eccentric and irregular,with round to oval morphology, grossly lacy chromatin and single or multiple evident nucleoli. These cells exhibited markedanisocytosis, anisokaryosis and pleomorphism, with more than one mitotic figure per high magnification field visible. Mildinflammatory infiltrate, predominantly lymphocytic, permeated the neoplastic cells, and marked depletion of lymphoidfollicles and atrophy of the red pulp were found in the remaining splenic parenchyma. Immunohistochemical tests...(AU)

Progesterone and estrogen receptor expression by canine cutaneous soft tissue sarcomas / Expressão de receptores para progesterona e estrógeno em sarcomas de tecidos moles cutâneos em cães

Canine soft tissue sarcomas (STS) comprise a heterogeneous group of malignancies that share similar histopathological features, a low to moderate recurrence rate and low metastatic potential. In human medicine, the expression of estrogen receptors (ER) and progesterone receptors (PR) in sarcomas has been studied to search for prognostic factors and new treatment targets. Similar studies have yet to be conducted in veterinary medicine. The objective of this study was therefore to investigate by immunohistochemistry (IHC) the ER and PR expression in a series of 80 cutaneous and subcutaneous sarcomas in dogs with histopathological features of peripheral nerve sheath tumor (PNST) and perivascular wall tumor (PWT). All cases were positive for PR and negative for ER. Tumors of high malignancy grade (grade III) exhibited higher PR expression than low-grade tumors (grade I). Tumors with mitotic activity greater than 9 mitotic figures/10 high power fields also exhibited higher PR expression. In addition, there was a positive correlation between cell proliferation (Ki67) and PR expression. Therefore, it is possible that progesterone plays a greater role than estrogen in the pathogenesis of these tumors. Future studies should explore the potential for selective progesterone receptor modulators as therapeutic agents in canine STS, as well as evaluating PR expression as a predictor of prognosis.(AU)

Sarcomas de tecidos moles (STM) caninos compreendem um grupo heterogêneo de neoplasias malignas, que apresentam alterações histopatológicas similares, baixa a moderada taxa de recorrência e baixo potencial metastático. Em medicina humana, a expressão de receptor para estrógeno (RE) e receptor para progesterona (RP) nos sarcomas tem sido estudada, visando a busca por fatores prognósticos e novos alvos para tratamentos. Na medicina veterinária, ainda não foram realizados estudos similares. O objetivo deste trabalho foi investigar por imuno-histoquímica a expressão de RE e RP em uma série de 80 sarcomas cutâneos e subcutâneos de cães, com características histopatológicas de tumor de bainha de nervo periférico e tumor de parede perivascular. Todos os casos foram positivos para RP e negativos para RE. Tumores de alto grau de malignidade (grau III) exibiram maior expressão deste receptor que os tumores de baixo grau (grau I). Tumores com atividade mitótica maior que 9 figuras mitóticas/10 campos de grande aumento também exibiram maior expressão do RP. Em adição, houve correlação positiva entre o índice de proliferação celular (Ki67) e a expressão de RP. Assim, é possível que a progesterona desempenhe maior papel que o estrógeno na patogênese desses tumores. Futuros trabalhos poderão explorar o potencial dos moduladores seletivos de RP como agente terapêutico em STM caninos, bem como avaliar a expressão de RP como preditiva de prognóstico.(AU)

Progesterone and estrogen receptor expression by canine cutaneous soft tissue sarcomas / Expressão de receptores para progesterona e estrógeno em sarcomas de tecidos moles cutâneos em cães

Canine soft tissue sarcomas (STS) comprise a heterogeneous group of malignancies that share similar histopathological features, a low to moderate recurrence rate and low metastatic potential. In human medicine, the expression of estrogen receptors (ER) and progesterone receptors (PR) in sarcomas has been studied to search for prognostic factors and new treatment targets. Similar studies have yet to be conducted in veterinary medicine. The objective of this study was therefore to investigate by immunohistochemistry (IHC) the ER and PR expression in a series of 80 cutaneous and subcutaneous sarcomas in dogs with histopathological features of peripheral nerve sheath tumor (PNST) and perivascular wall tumor (PWT). All cases were positive for PR and negative for ER. Tumors of high malignancy grade (grade III) exhibited higher PR expression than low-grade tumors (grade I). Tumors with mitotic activity greater than 9 mitotic figures/10 high power fields also exhibited higher PR expression. In addition, there was a positive correlation between cell proliferation (Ki67) and PR expression. Therefore, it is possible that progesterone plays a greater role than estrogen in the pathogenesis of these tumors. Future studies should explore the potential for selective progesterone receptor modulators as therapeutic agents in canine STS, as well as evaluating PR expression as a predictor of prognosis.(AU)

Sarcomas de tecidos moles (STM) caninos compreendem um grupo heterogêneo de neoplasias malignas, que apresentam alterações histopatológicas similares, baixa a moderada taxa de recorrência e baixo potencial metastático. Em medicina humana, a expressão de receptor para estrógeno (RE) e receptor para progesterona (RP) nos sarcomas tem sido estudada, visando a busca por fatores prognósticos e novos alvos para tratamentos. Na medicina veterinária, ainda não foram realizados estudos similares. O objetivo deste trabalho foi investigar por imuno-histoquímica a expressão de RE e RP em uma série de 80 sarcomas cutâneos e subcutâneos de cães, com características histopatológicas de tumor de bainha de nervo periférico e tumor de parede perivascular. Todos os casos foram positivos para RP e negativos para RE. Tumores de alto grau de malignidade (grau III) exibiram maior expressão deste receptor que os tumores de baixo grau (grau I). Tumores com atividade mitótica maior que 9 figuras mitóticas/10 campos de grande aumento também exibiram maior expressão do RP. Em adição, houve correlação positiva entre o índice de proliferação celular (Ki67) e a expressão de RP. Assim, é possível que a progesterona desempenhe maior papel que o estrógeno na patogênese desses tumores. Futuros trabalhos poderão explorar o potencial dos moduladores seletivos de RP como agente terapêutico em STM caninos, bem como avaliar a expressão de RP como preditiva de prognóstico.(AU)

Primary hepatic fibrosarcoma in a Wistar rat (Rattus norvegicus)

Soft tissue sarcomas are a heterogeneous group of malignant neoplasms with different morphological patterns of mesenchymal lineage. This type of neoplasm is most commonly found in the subcutaneous tissue but is rare in solid organs, such as the liver and kidneys. This paper describes the main anatomopathological alterations in the liver of a Wistar rat(Rattus norvegicus) with soft tissue sarcoma. A two-year-old male pet Wistar rat was referred to the Laboratory of Veterinary Pathology at the Federal University of Fronteira Sul. The owner reported apathy and the animal died during physical examination. At necropsy, 10 ml of a reddish liquid was found in the thoracic cavity. The left lateral liver lobec ontained a 5-cm mass of heterogeneous surface composed of whitish parenchyma and red multifocal lesions extending to the surface of the liver. Moreover, whitish dotted spots intercalated with dark and more friable spots were found in the whole left lateral liver lobe. Histopathological evaluation of the nodule revealed the formation of spindle cells in parallel bundles with slightly eosinophilic cytoplasm, elongated nucleus, hyperchromatic to granular chromatin, and inconspicuous nucleolus. Extracellular matrix and mineralization were also observed. An area with proliferation of spindle cells with elongated cytoplasm, round to oval nuclei, sometimes hyperchromatic, consistent with cells found in the liver was noted in the mesenteric lymph node and omental node. Masson Trichrome staining revealed tumor cells stained in blue. Immunohistochemistry was performed and revealed positive staining for vimentin and negative for pan-cytokeratin, S100,desmin and factor VIII. Thus, the histological, histochemical and immunohistochemical evaluations suggested hepatic fibrosarcoma. This report showed the histological and immunohistochemical findings of a poorly described tumor in a Wister rat in veterinary literature.

Primary hepatic fibrosarcoma in a Wistar rat (Rattus norvegicus)

Soft tissue sarcomas are a heterogeneous group of malignant neoplasms with different morphological patterns of mesenchymal lineage. This type of neoplasm is most commonly found in the subcutaneous tissue but is rare in solid organs, such as the liver and kidneys. This paper describes the main anatomopathological alterations in the liver of a Wistar rat(Rattus norvegicus) with soft tissue sarcoma. A two-year-old male pet Wistar rat was referred to the Laboratory of Veterinary Pathology at the Federal University of Fronteira Sul. The owner reported apathy and the animal died during physical examination. At necropsy, 10 ml of a reddish liquid was found in the thoracic cavity. The left lateral liver lobec ontained a 5-cm mass of heterogeneous surface composed of whitish parenchyma and red multifocal lesions extending to the surface of the liver. Moreover, whitish dotted spots intercalated with dark and more friable spots were found in the whole left lateral liver lobe. Histopathological evaluation of the nodule revealed the formation of spindle cells in parallel bundles with slightly eosinophilic cytoplasm, elongated nucleus, hyperchromatic to granular chromatin, and inconspicuous nucleolus. Extracellular matrix and mineralization were also observed. An area with proliferation of spindle cells with elongated cytoplasm, round to oval nuclei, sometimes hyperchromatic, consistent with cells found in the liver was noted in the mesenteric lymph node and omental node. Masson Trichrome staining revealed tumor cells stained in blue. Immunohistochemistry was performed and revealed positive staining for vimentin and negative for pan-cytokeratin, S100,desmin and factor VIII. Thus, the histological, histochemical and immunohistochemical evaluations suggested hepatic fibrosarcoma. This report showed the histological and immunohistochemical findings of a poorly described tumor in a Wister rat in veterinary literature.(AU)

Bilateral double-pigtail ureteral stent placement for management of ureteral obstruction secondary to transitional cell carcinoma in a dog

Background: Transitional cell carcinoma (TCC) usually affects the trigone region of the bladder and proximal portionof the urethra. TCC in dogs is often complicated by local tumor invasion and obstruction of the urethra, ureters, or both.Urinary obstruction is the cause of death in approximately 60% of dogs with TCC. Radical surgeries are associated withmorbidity and mortality rates. Stents have recently been evaluated for use in dogs with ureteral obstruction resulting froma variety of urinary tract tumors. This report aims to describe bilateral ureteral stent placement for treatment of malignantureteral obstruction and long-term follow-up in a dog.Case: An 11-year-old female spayed Maltese dog with ureteral obstruction secondary to transitional cell carcinoma (TCC)in the bladder trigone. After palliative debulking procedure and diagnostic of TCC in bladder and NSAIDs treatment,recurrence has occurred causing ureteral obstruction and TCC had invaded the abdominal wall. Abdominal wall localtumor resection, trigone mass debulking and bilateral ureteral stent placement was made. A double-pigtail ureteral stentof appropriate length was advanced to bypass the ureteral obstruction. Stent sizes were 3.5 Fr in diameter and from 8 to32 cm in length. The patient underwent surgical resection of the transitional cell carcinoma in the abdominal wall. Thecorrect location of the bilateral ureteral pigtail stent was certified by abdominal radiography. Recovery was uneventfuland the dog was discharged 2 days after surgery. Eleven months after stent placement, the dog developed lumbar vertebrae metastasis, without evidence of recurrent ureteral obstruction. The owners elected euthanasia 517 days after originalpresentation and 337 days after ureteral stent placement. Euthanasia was unrelated to the local tumor obstruction but was...

Bilateral double-pigtail ureteral stent placement for management of ureteral obstruction secondary to transitional cell carcinoma in a dog

Background: Transitional cell carcinoma (TCC) usually affects the trigone region of the bladder and proximal portionof the urethra. TCC in dogs is often complicated by local tumor invasion and obstruction of the urethra, ureters, or both.Urinary obstruction is the cause of death in approximately 60% of dogs with TCC. Radical surgeries are associated withmorbidity and mortality rates. Stents have recently been evaluated for use in dogs with ureteral obstruction resulting froma variety of urinary tract tumors. This report aims to describe bilateral ureteral stent placement for treatment of malignantureteral obstruction and long-term follow-up in a dog.Case: An 11-year-old female spayed Maltese dog with ureteral obstruction secondary to transitional cell carcinoma (TCC)in the bladder trigone. After palliative debulking procedure and diagnostic of TCC in bladder and NSAIDs treatment,recurrence has occurred causing ureteral obstruction and TCC had invaded the abdominal wall. Abdominal wall localtumor resection, trigone mass debulking and bilateral ureteral stent placement was made. A double-pigtail ureteral stentof appropriate length was advanced to bypass the ureteral obstruction. Stent sizes were 3.5 Fr in diameter and from 8 to32 cm in length. The patient underwent surgical resection of the transitional cell carcinoma in the abdominal wall. Thecorrect location of the bilateral ureteral pigtail stent was certified by abdominal radiography. Recovery was uneventfuland the dog was discharged 2 days after surgery. Eleven months after stent placement, the dog developed lumbar vertebrae metastasis, without evidence of recurrent ureteral obstruction. The owners elected euthanasia 517 days after originalpresentation and 337 days after ureteral stent placement. Euthanasia was unrelated to the local tumor obstruction but was...(AU)

Ablação de neoplasia no vestíbulo da cavidade oral de equino / Neoplasia ablation in the equine oral cavity vestibule

Background: Oral squamous cell carcinoma is responsible for more than 90% of head and neck neoplasms in humans.Multiple factors are associated with the development of squamous cell carcinomas in humans and animals, such as prolonged exposure to ultraviolet light, lack of pigment in the epidermis, or sparse hair coverage. In horses, oral forms arerare and represent 7% of cases, but sarcoids are the main type of oral neoplasia. In the present case, due to the location andanatomical dimensions of the oral vestibule, it was necessary to adapt it to the natural tumor excision, a fact that aimedto describe this report.Case: One Arabian 2- year-old male horse, treated at the Veterinary Hospital of the Santa Cruz State University (UESC),with signs of severe mouth bleeding and halitosis. Clinical inspection of the face showed elevation in the masseter regionand left mandible branch. Clinical examination of the oral cavity revealed soft tissue tumor extending from tooth 308(PM-1, lower left) to 311 (M-3, lower left) and on the buccal surface of the left mandible branch. Radiographic examination revealed no invasion of bone tissue by the tumor. Biopsy material was collected. The histopathological report was ofneoplastic cell proliferation, frequent mitoses, binucleate cells and extensive ulceration area associated with neutrophilicinflammatory infiltrate, indicative of squamous cell carcinoma. The animal was referred to the Surgical Sector who, afterevaluation of the animal, opted for the ablation of the neoplasia. Pre-anesthesia performed with intravenous detomidine30 µg/kg, anesthesia with regional mandibular nerve block with 20 mL of 2% lidocaine and maintenance with continuousinfusion of detoxid 0.5 µg/kg/ min. Contention for the operative act in the quadrupedal...

Ablação de neoplasia no vestíbulo da cavidade oral de equino / Neoplasia ablation in the equine oral cavity vestibule

Background: Oral squamous cell carcinoma is responsible for more than 90% of head and neck neoplasms in humans.Multiple factors are associated with the development of squamous cell carcinomas in humans and animals, such as prolonged exposure to ultraviolet light, lack of pigment in the epidermis, or sparse hair coverage. In horses, oral forms arerare and represent 7% of cases, but sarcoids are the main type of oral neoplasia. In the present case, due to the location andanatomical dimensions of the oral vestibule, it was necessary to adapt it to the natural tumor excision, a fact that aimedto describe this report.Case: One Arabian 2- year-old male horse, treated at the Veterinary Hospital of the Santa Cruz State University (UESC),with signs of severe mouth bleeding and halitosis. Clinical inspection of the face showed elevation in the masseter regionand left mandible branch. Clinical examination of the oral cavity revealed soft tissue tumor extending from tooth 308(PM-1, lower left) to 311 (M-3, lower left) and on the buccal surface of the left mandible branch. Radiographic examination revealed no invasion of bone tissue by the tumor. Biopsy material was collected. The histopathological report was ofneoplastic cell proliferation, frequent mitoses, binucleate cells and extensive ulceration area associated with neutrophilicinflammatory infiltrate, indicative of squamous cell carcinoma. The animal was referred to the Surgical Sector who, afterevaluation of the animal, opted for the ablation of the neoplasia. Pre-anesthesia performed with intravenous detomidine30 µg/kg, anesthesia with regional mandibular nerve block with 20 mL of 2% lidocaine and maintenance with continuousinfusion of detoxid 0.5 µg/kg/ min. Contention for the operative act in the quadrupedal...(AU)

Inflammatory lesions and brain tumors: is it possible to differentiate them based on texture features in magnetic resonance imaging?

Neuroimaging strategies are essential to locate, to elucidate the etiology, and to the follow up of brain disease patients. Magnetic resonance imaging (MRI) provides good cerebral soft-tissue contrast detection and diagnostic sensitivity. Inflammatory lesions and tumors are common brain diseases that may present a similar pattern of a cerebral ring enhancing lesion on MRI, and non-enhancing core (which may reflect cystic components or necrosis) leading to misdiagnosis. Texture analysis (TA) and machine learning approaches are computer-aided diagnostic tools that can be used to assist radiologists in such decisions. Methods: In this study, we combined texture features with machine learning (ML) methods aiming to differentiate brain tumors from inflammatory lesions in magnetic resonance imaging. Retrospective examination of 67 patients, with a pattern of a cerebral ring enhancing lesion, 30 with inflammatory, and 37 with tumoral lesions were selected. Three different MRI sequences and textural features were extracted using gray level co-occurrence matrix and gray level run length. All diagnoses were confirmed by histopathology, laboratorial analysis or MRI. Results: The features extracted were processed for the application of ML methods that performed the classification. T1-weighted images proved to be the best sequence for classification, in which the differentiation between inflammatory and tumoral lesions presented high accuracy (0.827), area under ROC curve (0.906), precision (0.837), and recall (0.912). Conclusion: The algorithm obtained textures capable of differentiating brain tumors from inflammatory lesions, on T1-weghted images without contrast medium using the Random Forest machine learning classifier.(AU)