Nasal leiomyosarcoma in a Quarter Horse / Leiomiossarcoma nasal em equino Quarto de Milha

We described the clinical and anatomopathological findings observed in a case of nasal leiomyosarcoma in a five-year-old male Quarter Mile horse, whose main complaints were decreased sports performance and bilateral purulent nasal discharge. The nodule was observed in the nasal cavity, obstructing the left nostril and associated with purulent drainage. The nodule was of irregular shape and yellow color, measuring 19.4 cm × 6.9 cm × 4.3 cm in size, with coalescent multifocal areas that were brownish, friable, opaque, and fetid. When cut, the surface was compact, grayish-white, and smooth with yellow, friable, irregular multifocal areas, measuring 1-3.2 cm in diameter. Histopathological examination showed spindle-shaped neoplastic cells, which was negative on Masson's trichromic stain. A diagnosis of leiomyosarcoma was established based on the morphotintorial aspects of neoplastic cells and confirmed through immunohistochemistry, with positive immunostaining for antibodies 1A4, HHF35, desmin, and S100. Leiomyosarcoma primarily affects the nasal cavity of horses and should be included in the differential diagnosis of diseases that affect the nasal cavity and cause nasal obstruction associated with dyspnea.

Descreve-se os achados clínicos e anatomopatológicos observados em um caso de leiomiossarcoma nasal em um equino, Quarto de Milha, macho, de cinco anos de idade, com queixa principal de diminuição do rendimento esportivo e secreção nasal purulenta bilateral. Na cavidade nasal, observou-se um nódulo obstruindo a narina esquerda associada à secreção purulenta. O nódulo era de superfície irregular, amarelada, brilhante, fibroelástica, medindo 19,4 x 6,9 x 4,3cm de tamanho, com áreas multifocais a coalescente acastanhadas, friáveis, opacas e fétidas. Ao corte, a superfície era compacta, branco-acinzentada e lisa com áreas multifocais amarelas, friáveis e irregulares, medindo 1-3,2 cm de diâmetro. No exame histopatológico foi observado proliferação de células neoplásicas fusiformes, que foram negativas na coloração de Tricrômico de Masson. O diagnóstico de leiomiossarcoma foi estabelecido com base nos aspectos morfotintoriais das células neoplásicas e confirmado através da imuno-histoquímica, no qual houve imunomarcação positiva para os anticorpos 1A4, HHF35, Desmina e S100. O leiomiossarcoma pode afetar primariamente a cavidade nasal de equinos, devendo ser incluído no diagnóstico diferencial de doenças que afetam a cavidade nasal e que provocam quadros de obstrução nasal associado a dispneia.

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)

Surgical treatment associated with adjuvant chemotherapy with cyclophosphamide and piroxicam in cervical sarcoma of a blue-fronted amazon (Amazona aestiva): case report / Tratamento cirúrgico com uso de quimioterapia adjuvante com ciclofosfamida e piroxicam em sarcoma cervical de um papagaio-verdadeiro (Amazona aestiva): relato de caso

The occurrence of neoplasms in birds is still unknown, with the literature based mainly on scarce reports, in this context, data about epidemiology in specific species are almost nonexistent. Sarcomas are malignant mesenchymal origin neoplasms, which can develop from different tissues, such as adipose, cartilage, bone, among others. The occurrence of sarcomas in birds has been previously described, with different therapeutic approaches. The present report describes the clinical approach in a blue-fronted amazon (Amazona aestiva) diagnosed with a soft tissue sarcoma in the dorsal cervical region, with surgical excision associated with a metronomic chemotherapy protocol as an adjuvant. The therapeutic combination proved to be effective in controlling the disease, guaranteeing important survival, with clinical absence of side effects.

A ocorrência das neoplasias em aves ainda é desconhecida, com a literatura se baseando principalmente em relatos escassos, nesse contexto, dados acerca de epidemiologia em espécies específicas são quase inexistentes. Os sarcomas são neo-plasias malignas de origem mesenquimal, podendo se desenvolver a partir de tecidos diversos, como adiposo, cartilaginoso, ósseo, dentre outros. A ocorrência de sarcomas em aves já foi previamente descrita, com diferentes abordagens terapêuticas. O presente relato descreve a abordagem clínica em um papagaio-verdadeiro (Amazona aestiva) diagnosticado com um sarcoma de tecidos moles em região cervical dorsal, sendo realizada a exérese cirúrgica associada a protocolo quimioterápico metronô-mico em caráter adjuvante. A combinação terapêutica se mostrou eficaz no controle da doença, garantindo sobrevida impor-tante, na ausência clínica de efeitos colaterais.

Surgical treatment associated with adjuvant chemotherapy with cyclophosphamide and piroxicam in cervical sarcoma of a blue-fronted amazon (Amazona aestiva): case report / Tratamento cirúrgico com uso de quimioterapia adjuvante com ciclofosfamida e piroxicam em sarcoma cervical de um papagaio-verdadeiro (Amazona aestiva): relato de caso

The occurrence of neoplasms in birds is still unknown, with the literature based mainly on scarce reports, in this context, data about epidemiology in specific species are almost nonexistent. Sarcomas are malignant mesenchymal origin neoplasms, which can develop from different tissues, such as adipose, cartilage, bone, among others. The occurrence of sarcomas in birds has been previously described, with different therapeutic approaches. The present report describes the clinical approach in a blue-fronted amazon (Amazona aestiva) diagnosed with a soft tissue sarcoma in the dorsal cervical region, with surgical excision associated with a metronomic chemotherapy protocol as an adjuvant. The therapeutic combination proved to be effective in controlling the disease, guaranteeing important survival, with clinical absence of side effects.(AU)

A ocorrência das neoplasias em aves ainda é desconhecida, com a literatura se baseando principalmente em relatos escassos, nesse contexto, dados acerca de epidemiologia em espécies específicas são quase inexistentes. Os sarcomas são neo-plasias malignas de origem mesenquimal, podendo se desenvolver a partir de tecidos diversos, como adiposo, cartilaginoso, ósseo, dentre outros. A ocorrência de sarcomas em aves já foi previamente descrita, com diferentes abordagens terapêuticas. O presente relato descreve a abordagem clínica em um papagaio-verdadeiro (Amazona aestiva) diagnosticado com um sarcoma de tecidos moles em região cervical dorsal, sendo realizada a exérese cirúrgica associada a protocolo quimioterápico metronô-mico em caráter adjuvante. A combinação terapêutica se mostrou eficaz no controle da doença, garantindo sobrevida impor-tante, na ausência clínica de efeitos colaterais.(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.

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)

Sarcoma de tecidos moles em cães: a ressecção cirúrgica cura? / Soft tissue sarcomas in dogs: does surgical resection heal?

Os sarcomas de tecidos moles (STM) são um grupo de diferentes tipos de tumores de origem mesenquimal; descritos como massas pseu-doencapsuladas com margens mal definidas que apresentam índices altos de recidiva local em comparação ao baixo a moderado potencial metastático. Ocorrem tanto em seres humanos quanto em animais; compreendem aproximadamente 15% de todos os tumores de pele e de subcutâneo em cães. Devido ao seu comportamento invasivo, a remoção cirúrgica é o tratamento indicado para os cães acometidos por tais tumores, incluindo-se também a radioterapia após ressecção incompleta, pois o papel da quimioterapia ainda é pouco conhecido.

Soft tissue sarcomas (STS), a heterogeneous group of different tumors of mesenchymal origin, are described as pseudo-encapsulated masses with poor defined margins that present high rates of local recurrence compared to the low to moderate metastatic potential. They can occur both in humans and animals, and in dogs they comprise approximately 15% of all skin and subcutaneous tumors. Due to its invasive behavior, surgery is the main treatment applied for these tumors in dogs, and it can be combined to radiotherapy after the incomplete resection because the role of chemotherapy is still very poorly understood in this subject.

Sarcoma de tecidos moles em cães: a ressecção cirúrgica cura? / Soft tissue sarcomas in dogs: does surgical resection heal?

Os sarcomas de tecidos moles (STM) são um grupo de diferentes tipos de tumores de origem mesenquimal; descritos como massas pseu-doencapsuladas com margens mal definidas que apresentam índices altos de recidiva local em comparação ao baixo a moderado potencial metastático. Ocorrem tanto em seres humanos quanto em animais; compreendem aproximadamente 15% de todos os tumores de pele e de subcutâneo em cães. Devido ao seu comportamento invasivo, a remoção cirúrgica é o tratamento indicado para os cães acometidos por tais tumores, incluindo-se também a radioterapia após ressecção incompleta, pois o papel da quimioterapia ainda é pouco conhecido.(AU)

Soft tissue sarcomas (STS), a heterogeneous group of different tumors of mesenchymal origin, are described as pseudo-encapsulated masses with poor defined margins that present high rates of local recurrence compared to the low to moderate metastatic potential. They can occur both in humans and animals, and in dogs they comprise approximately 15% of all skin and subcutaneous tumors. Due to its invasive behavior, surgery is the main treatment applied for these tumors in dogs, and it can be combined to radiotherapy after the incomplete resection because the role of chemotherapy is still very poorly understood in this subject. (AU)

Sarcoma de sítio de aplicação em felinos / Feline injection-site sarcoma

Sarcomas de sítio de aplicação são neoplasias malignas de origem mesenquimal caracterizadas pelo comportamento biológico agressivo. Apesar da extensa pesquisa, a patogênese da doença ainda não está totalmente esclarecida, acredita-se que a administração de vacinas, medicamentos e outros injetáveis no tecido subcutâneo ou intramuscular em gatos predispostos, possa induzir uma reação inflamatória crônica e, posteriormente, a transformação neoplásica. O diagnóstico é realizado por meio da biópsia, porém deve ser feito avaliação da extensão do tumor primário, o estadiamento padrão e a avaliação geral da saúde desses pacientes. A abordagem terapêutica multimodal, associando a excisão cirúrgica radical à radioterapia, quimioterapia ou imunoterapia, tem demonstrado melhores resultados. A escolha do local de injeção, frequência de vacinação e recomendações para reduzir a reação inflamatória são considerações importantes para a prevenção. O objetivo desta revisão é fornecer uma visão geral do atual conhecimento sobre sarcoma de sítio de aplicação em felinos.

Injection-site sarcomas are malignant neoplasms whose mesenchymal origin is characterized by aggressive biological behavior, developing from various tissues, being fibrosarcoma the most common histological type in felines. Despite wide research, the pathogenesis of the disease is still not fully understood, the most accepted hypothesis suggests that administration of vaccines, medications and other injectables into the subcutaneous or intramuscular tissue of predisposed cats may induce a chronic inflammatory reaction and, subsequently, neoplastic transformation. Related to epidemiology, it presents low prevalence and high rates of regress even after aggressive treatments. The diagnosis is performed through biopsy and histopathological examination, assessmentof the extent of the primary tumor, the standard staging and general evaluation of the health of these patients. The multimodal therapeutic approach, associating radical surgical excision with radiotherapy, chemotherapy or immunotherapy, has shown better results. Choosing the injection site, frequency of vaccination and recommendations to reduce the inflammatory reaction are important considerations for prevention. The aim of this review is to provide an overview of the current knowledge on feline application site sarcoma.

Sarcoma de sítio de aplicação em felinos / Feline injection-site sarcoma

Sarcomas de sítio de aplicação são neoplasias malignas de origem mesenquimal caracterizadas pelo comportamento biológico agressivo. Apesar da extensa pesquisa, a patogênese da doença ainda não está totalmente esclarecida, acredita-se que a administração de vacinas, medicamentos e outros injetáveis no tecido subcutâneo ou intramuscular em gatos predispostos, possa induzir uma reação inflamatória crônica e, posteriormente, a transformação neoplásica. O diagnóstico é realizado por meio da biópsia, porém deve ser feito avaliação da extensão do tumor primário, o estadiamento padrão e a avaliação geral da saúde desses pacientes. A abordagem terapêutica multimodal, associando a excisão cirúrgica radical à radioterapia, quimioterapia ou imunoterapia, tem demonstrado melhores resultados. A escolha do local de injeção, frequência de vacinação e recomendações para reduzir a reação inflamatória são considerações importantes para a prevenção. O objetivo desta revisão é fornecer uma visão geral do atual conhecimento sobre sarcoma de sítio de aplicação em felinos.(AU)

Injection-site sarcomas are malignant neoplasms whose mesenchymal origin is characterized by aggressive biological behavior, developing from various tissues, being fibrosarcoma the most common histological type in felines. Despite wide research, the pathogenesis of the disease is still not fully understood, the most accepted hypothesis suggests that administration of vaccines, medications and other injectables into the subcutaneous or intramuscular tissue of predisposed cats may induce a chronic inflammatory reaction and, subsequently, neoplastic transformation. Related to epidemiology, it presents low prevalence and high rates of regress even after aggressive treatments. The diagnosis is performed through biopsy and histopathological examination, assessmentof the extent of the primary tumor, the standard staging and general evaluation of the health of these patients. The multimodal therapeutic approach, associating radical surgical excision with radiotherapy, chemotherapy or immunotherapy, has shown better results. Choosing the injection site, frequency of vaccination and recommendations to reduce the inflammatory reaction are important considerations for prevention. The aim of this review is to provide an overview of the current knowledge on feline application site sarcoma.(AU)

Histopathology and immunohistochemistry of peripheral neural sheath tumor and perivascular wall tumor in dog / Histopatologia e imuno-histoquímica de tumor de bainha de nervo periférico e de tumor de parede perivascular em cães

Soft tissue sarcomas (STS) comprise a heterogeneous group of malignancies derived from extra-skeletal mesenchymal tissues that may show similar histopathological changes. Histopathologic patterns suggestive of perivascular wall tumors (PWT) and peripheral nerve sheath tumors (PNST) have been described. This study investigated the histogenesis in a series of 71 cases of canine STS that showed morphological compatibility with what is described for PWT and PNST. Immunohistochemistry analysis were done to CD56, S100, SMA, Desmin, Von Willebrand Factor, NSE and GFAP. Twenty-one cases (29.6%) showed histopathologic features compatible with PWT, 23 cases (32.4%) with PNST and 27 cases (38.0%) shared both histopathological features. By immunohistochemistry, 59 (83.1%) cases showed positivity only for neural markers and 12 (16.9%) had simultaneous positivity for both neural and muscle markers. PNST was the most prevalent neoplasm and none of the cases were positive for muscle markers only. The histopathologic features were not useful to define the diagnosis of PWT, since most tumors were negative for muscle markers but positive for neural markers. Due to this immunoreactivity and the morphologic features, future studies may propose guidelines for the classification of these neoplasms.(AU)

Sarcoma de tecidos moles (STM) compreende um grupo heterogêneo de neoplasias malignas, derivadas de tecidos extraesqueléticos, que podem apresentar alterações histopatológicas similares. Os padrões histopatológicos sugestivos de tumor de parede perivascular (TPP) e de tumor de bainha de nervo periférico (TBNP) têm sido descritos. Este estudo investigou a histogênese de uma série de 71 STM caninos, que apresentavam compatibilidade morfológica com o que é descrito para TPP e TBNP. A análise imuno-histoquímica foi feita para CD56, S100, SMA, Desmina, Fator Von Willebrand, NSE e GFAP. Vinte e um casos (29,6%) apresentaram características histopatológicas compatíveis com TPP, 23 casos (32,4%) com TBNP e 27 casos (38,0%) apresentaram características histopatológicas de ambos. Na imuno-histoquímica, 59 (83,1%) casos apresentaram positividade somente para marcadores neurais e 12 (16,9%) tiveram positividade simultânea tanto para marcadores neurais como para marcadores musculares. TBNP foi a neoplasia mais prevalente e nenhum dos casos foi positivo para somente para marcadores musculares. As características histopatológicas não foram úteis para definir o diagnóstico de TPP, uma vez que a maioria foi negativa para marcadores musculares, mas positiva para marcadores neurais. Devido a essa imunorreatividade e às características morfológicas, pesquisas futuras poderão propor orientações para a classificação dessas neoplasias.(AU)

Histopathology and immunohistochemistry of peripheral neural sheath tumor and perivascular wall tumor in dog / Histopatologia e imuno-histoquímica de tumor de bainha de nervo periférico e de tumor de parede perivascular em cães

Soft tissue sarcomas (STS) comprise a heterogeneous group of malignancies derived from extra-skeletal mesenchymal tissues that may show similar histopathological changes. Histopathologic patterns suggestive of perivascular wall tumors (PWT) and peripheral nerve sheath tumors (PNST) have been described. This study investigated the histogenesis in a series of 71 cases of canine STS that showed morphological compatibility with what is described for PWT and PNST. Immunohistochemistry analysis were done to CD56, S100, SMA, Desmin, Von Willebrand Factor, NSE and GFAP. Twenty-one cases (29.6%) showed histopathologic features compatible with PWT, 23 cases (32.4%) with PNST and 27 cases (38.0%) shared both histopathological features. By immunohistochemistry, 59 (83.1%) cases showed positivity only for neural markers and 12 (16.9%) had simultaneous positivity for both neural and muscle markers. PNST was the most prevalent neoplasm and none of the cases were positive for muscle markers only. The histopathologic features were not useful to define the diagnosis of PWT, since most tumors were negative for muscle markers but positive for neural markers. Due to this immunoreactivity and the morphologic features, future studies may propose guidelines for the classification of these neoplasms.(AU)

Sarcoma de tecidos moles (STM) compreende um grupo heterogêneo de neoplasias malignas, derivadas de tecidos extraesqueléticos, que podem apresentar alterações histopatológicas similares. Os padrões histopatológicos sugestivos de tumor de parede perivascular (TPP) e de tumor de bainha de nervo periférico (TBNP) têm sido descritos. Este estudo investigou a histogênese de uma série de 71 STM caninos, que apresentavam compatibilidade morfológica com o que é descrito para TPP e TBNP. A análise imuno-histoquímica foi feita para CD56, S100, SMA, Desmina, Fator Von Willebrand, NSE e GFAP. Vinte e um casos (29,6%) apresentaram características histopatológicas compatíveis com TPP, 23 casos (32,4%) com TBNP e 27 casos (38,0%) apresentaram características histopatológicas de ambos. Na imuno-histoquímica, 59 (83,1%) casos apresentaram positividade somente para marcadores neurais e 12 (16,9%) tiveram positividade simultânea tanto para marcadores neurais como para marcadores musculares. TBNP foi a neoplasia mais prevalente e nenhum dos casos foi positivo para somente para marcadores musculares. As características histopatológicas não foram úteis para definir o diagnóstico de TPP, uma vez que a maioria foi negativa para marcadores musculares, mas positiva para marcadores neurais. Devido a essa imunorreatividade e às características morfológicas, pesquisas futuras poderão propor orientações para a classificação dessas neoplasias.(AU)

Neuropathic pain and prognosis of a dog submitted to limb amputation after diagnosis of soft tissue sarcoma - case report / Dor neuropática e prognóstico de um cão submetido à amputação de membro após diagnóstico de sarcoma de tecidos moles - relato de caso

Neuropathic pain occurs when there is a lesion or a dysfunction of the nervous system. Humans and veterinary patients may develop neuropathic pain, but in veterinary it is not often reported probably because of its mistaken diagnosis. A canine patient was admitted to the Veterinary Hospital of UNESP-Jaboticabal-SP, Brazil with a nodule on the left thoracic limb. The nodule was surgically removed, and histopathological analysis demonstrated the tumor was a soft tissue sarcoma (STS) and the margins were not clean. Based on the patient's health condition and the lack of suitable equipment, the next procedure was limb amputation. The patient received analgesic medication in the post-surgery period; nevertheless, clinical signs of neuropathic pain were present, such as compulsive licking and other behavioral disorders. Medications were administered for forty days, but clinical signs ceased only when replaced with a tryciclic antidepressant drug, Amitriptyline. Therapeutic management of the patient in this report can be considered effective, since five years after the end of the treatment there was no recurrence or presence of metastasis.(AU)

A dor neuropática ocorre quando há uma lesão ou disfunção do sistema nervoso. Tanto pacientes humanos quanto veterinários podem desenvolver a dor neuropática, mas na medicina veterinária ela é pouco relatada provavelmente por não ser corretamente diagnosticada. Um paciente canino foi atendido no Hospital Veterinário da Unesp-Jaboticabal, SP, Brasil, com um nódulo em membro torácico esquerdo. O nódulo foi removido cirurgicamente, e o exame histopatológico evidenciou a presença de sarcoma de tecidos moles (STM) e de margens comprometidas. Baseando-se nas condições de saúde do paciente e na ausência de equipamentos adequados, o próximo procedimento foi a amputação do membro. No pós-cirúrgico, o animal recebeu medicações analgésicas, todavia, mesmo assim, apresentava sinais de dor neuropática, como lambedura compulsiva e outros distúrbios comportamentais. O tratamento para dor aguda se estendeu por 40 dias; no entanto, os sinais clínicos cessaram apenas quando os analgésicos comuns foram substituídos por um medicamento antidepressivo tricíclico, a amitriptilina. O manejo terapêutico do paciente do presente relato pode ser considerado satisfatório, uma vez que, após cinco anos do término do tratamento, não houve recidiva nem presença de metástase.(AU)

Neuropathic pain and prognosis of a dog submitted to limb amputation after diagnosis of soft tissue sarcoma - case report / Dor neuropática e prognóstico de um cão submetido à amputação de membro após diagnóstico de sarcoma de tecidos moles - relato de caso

Neuropathic pain occurs when there is a lesion or a dysfunction of the nervous system. Humans and veterinary patients may develop neuropathic pain, but in veterinary it is not often reported probably because of its mistaken diagnosis. A canine patient was admitted to the Veterinary Hospital of UNESP-Jaboticabal-SP, Brazil with a nodule on the left thoracic limb. The nodule was surgically removed, and histopathological analysis demonstrated the tumor was a soft tissue sarcoma (STS) and the margins were not clean. Based on the patient's health condition and the lack of suitable equipment, the next procedure was limb amputation. The patient received analgesic medication in the post-surgery period; nevertheless, clinical signs of neuropathic pain were present, such as compulsive licking and other behavioral disorders. Medications were administered for forty days, but clinical signs ceased only when replaced with a tryciclic antidepressant drug, Amitriptyline. Therapeutic management of the patient in this report can be considered effective, since five years after the end of the treatment there was no recurrence or presence of metastasis.(AU)

A dor neuropática ocorre quando há uma lesão ou disfunção do sistema nervoso. Tanto pacientes humanos quanto veterinários podem desenvolver a dor neuropática, mas na medicina veterinária ela é pouco relatada provavelmente por não ser corretamente diagnosticada. Um paciente canino foi atendido no Hospital Veterinário da Unesp-Jaboticabal, SP, Brasil, com um nódulo em membro torácico esquerdo. O nódulo foi removido cirurgicamente, e o exame histopatológico evidenciou a presença de sarcoma de tecidos moles (STM) e de margens comprometidas. Baseando-se nas condições de saúde do paciente e na ausência de equipamentos adequados, o próximo procedimento foi a amputação do membro. No pós-cirúrgico, o animal recebeu medicações analgésicas, todavia, mesmo assim, apresentava sinais de dor neuropática, como lambedura compulsiva e outros distúrbios comportamentais. O tratamento para dor aguda se estendeu por 40 dias; no entanto, os sinais clínicos cessaram apenas quando os analgésicos comuns foram substituídos por um medicamento antidepressivo tricíclico, a amitriptilina. O manejo terapêutico do paciente do presente relato pode ser considerado satisfatório, uma vez que, após cinco anos do término do tratamento, não houve recidiva nem presença de metástase.(AU)