Melanomas em cães no Sertão do Nordeste do Brasil - epidemiologia, fatores de risco e achados clinicopatológicos / Melanoma in dogs in the backlands of Northeastern Brazil - epidemiology, risk factors and clinicopathological findings

Background: Melanoma is a malignant neoplasm that arises from melanocytes and malanoblasts. It is also more frequently reported in dogs than in other species. They may arise from melanocytes in the skin, on the surfaces of the mucous membranes, and eyes. The aim of this study was to describe the epidemiological aspects, risk factors and clinicopathological findings of melanoma in dogs in the backlands, northeastern Brazil. Materials, Methods & Results: A retrospective study was carried out in all biopsy samples and necropsy examinations of dogs, from January 2003 to December 2021, at the Animal Pathology Laboratory of the Federal University of Campina Grande, Patos, Paraiba, northeastern Brazil. Epidemiological data, clinical signs, and gross lesions were reviewed from the diagnostic laboratory reports. Samples of the skin, lymph nodes, central nervous system and organs of the thoracic and abdominal cavities were fixed in 10% buffered formalin, processed routinely for histopathology, embedded in paraffin wax, cut into 4 µm sections, and stained with hematoxylin and eosin (HE). Histological sections were also submitted to immunohistochemistry with the primary antibody anti-Melan A. Of the 4717 records found, 1158 (24.5%) were diagnosed with neoplasms, of which 48 (4.14%) cases were of melanoma. Of this total, 28 (58.3%) dogs were elderly, 19 (39.6%) were adults, and 1 (2.1%) was young. Mixed breed animals were the most affected (42.6%), followed by the pinscher breed (19.1%). According to the anatomical region, the most affected site was the skin (38/53=71.7%), followed by the oral cavity (12/53=22.65%) and the eyes (3/53=5.7%). Grossly, the skin lesions were characterized by exophytic and usually blackened, sometimes irregular and firm, nodules. At cut, they had a smooth, compact and blackened surface. Lesions in the oral cavity were characterized by blackened, irregular and infiltrating nodules or masses. The ocular lesions were always unilateral and were characterized by an enlarged and diffusely blackened eyeball, with areas of ulceration and subversion of tissue architecture. In 5 animals there was more than one anatomical site affected, totaling 53 lesions. In 9 (17%) cases, metastases were identified, 8 in regional lymph nodes and 1 in the lung. Histopathology showed a densely non-encapsulated, poorly delimited, expansive and infiltrative neoplasm, composed of neoplastic cells arranged in islands or nests and supported by fibrovascular stroma, containing a variable amount of brownish pigment (melanin). Immunohistochemistry showed strong immunostaining of the neoplastic cells in brown by the anti-Melan A antibody. Discussion: The diagnosis of melanoma was established based on epidemiological, clinical, anatomopathological, and immunohistochemical findings. Gender is not a predisposing factor, and although there was no statistically significant relationship, males were more affected. Senescence is a conditioning risk factor. Elderly animals were more affected (P < 0.0001) than adult ones, with OR = 4.38; and young ones (P = 0.0051), with OR = 12.65. Some breeds, especially those with marked skin pigmentation, were more affected, however the most affected ones in this survey were pinscher and poodle. Cutaneous melanoma accounted for almost 72% of cases, contesting recent studies where oral cavity melanoma was more frequent. Therefore, it is believed that the climatic conditions of the backlands sub-region, in northeastern Brazil, associated with the individual characteristics of the dogs, are involved in the development of these neoplasms, since the climate is predominantly dry, with high temperatures throughout the year, with maximums that can reach 40ºC, favoring the exposure to high incidence of ultraviolet radiation.

Linfoma renal primário em cão / Primary kidney lymphoma in a dog

Background: Lymphoma is a malignant lymphoid tumor originating in the lymph nodes or other solid organs and comprises90% of all hematopoietic tumors in dogs. However, primary kidney lymphoma is rare and is associated with nonspecificclinical signs. Tumor invasion in both kidneys can cause severe clinical signs due to renal failure, complicating the patient’streatment and prognosis. The aim of this case was to report the case of a dog affected by bilateral primary kidney lymphoma. In addition, to characterize the clinical and histopathological presentation due to the intense morphological changes.Case: A 5-year-old male Poodle dog was admitted showing apathy and emesis for 5 days. On physical examination, thedog showed 10% of dehydration, reddish oral mucous membranes, poor body condition (score 1/5), uremic breath, andpain in the kidney area. Complementary tests revealed severe low white blood cells count, high BUN levels, high levels ofpotassium, calcium, and phosphorus (serum biochemistry). Abdominal ultrasound showed bilateral kidney enlargement.Fine needle aspiration of the mass (guided by ultrasound) revealed round cell tumor. Radiographs showed no alterations.The dog died due to his poor condition and necropsy was performed. On post-mortem examination, the kidneys were bothenlarged, pale, and with an irregular subcapsular surface. The histopathological diagnostic was primary renal lymphoma.Immunohistochemical staining revealed that neoplastic cells were strongly positive for anti CD20 and PAX5, while negative for CD3, supporting the diagnosis of B-cell lymphoma.Discussion: The diagnosis was based on clinical, complementary tests, fine needle aspiration, histopathological andimmunohistochemical findings. In dogs, primary kidney tumors are uncommon and usually malignant. The presence ofvomiting, uremic breath, dehydration, weight loss, and erosive and ulcerative lesions on the tongue (uremic glossitis)...

Linfoma renal primário em cão / Primary kidney lymphoma in a dog

Background: Lymphoma is a malignant lymphoid tumor originating in the lymph nodes or other solid organs and comprises90% of all hematopoietic tumors in dogs. However, primary kidney lymphoma is rare and is associated with nonspecificclinical signs. Tumor invasion in both kidneys can cause severe clinical signs due to renal failure, complicating the patientstreatment and prognosis. The aim of this case was to report the case of a dog affected by bilateral primary kidney lymphoma. In addition, to characterize the clinical and histopathological presentation due to the intense morphological changes.Case: A 5-year-old male Poodle dog was admitted showing apathy and emesis for 5 days. On physical examination, thedog showed 10% of dehydration, reddish oral mucous membranes, poor body condition (score 1/5), uremic breath, andpain in the kidney area. Complementary tests revealed severe low white blood cells count, high BUN levels, high levels ofpotassium, calcium, and phosphorus (serum biochemistry). Abdominal ultrasound showed bilateral kidney enlargement.Fine needle aspiration of the mass (guided by ultrasound) revealed round cell tumor. Radiographs showed no alterations.The dog died due to his poor condition and necropsy was performed. On post-mortem examination, the kidneys were bothenlarged, pale, and with an irregular subcapsular surface. The histopathological diagnostic was primary renal lymphoma.Immunohistochemical staining revealed that neoplastic cells were strongly positive for anti CD20 and PAX5, while negative for CD3, supporting the diagnosis of B-cell lymphoma.Discussion: The diagnosis was based on clinical, complementary tests, fine needle aspiration, histopathological andimmunohistochemical findings. In dogs, primary kidney tumors are uncommon and usually malignant. The presence ofvomiting, uremic breath, dehydration, weight loss, and erosive and ulcerative lesions on the tongue (uremic glossitis)...(AU)

Bone and pulmonary metastasis from a mammary adenosquamous carcinoma in a bitch / Metástase óssea e pulmonar de adenocarcinoma escamoso mamário em cadela

Mammary tumors are the most common in bitches, and bone and pulmonary metastases are not well described. Adenosquamous mammary carcinoma is a rare tumor that can be classified as a type of metaplastic tumor. This report describes the clinical and histopathological findings of this atypical presentation of mammary carcinoma in an 11-year-old, spayed, Poodle. Surgery was performed to remove malignant mammary nodules with a provisional diagnosis of carcinoma on cytologic examination. Thirteen months later, the dog returned showing left pelvic limb lameness that had persisted for 6 months prior to the consultation. The patient showed right pelvic limb lameness and a mass in the same limb. Radiographs of the affected limb revealed a pathological fracture in the femoral diaphysis and proliferation of the periosteum. After clinical staging, a left pelvic limb amputation was performed. A diagnosis of grade II adenosquamous mammary carcinoma was made through histopathology and immunohistochemistry. Although uncommon, bone and pulmonary metastases from mammary tumors, such as adenosquamous carcinoma, can be considered differential diagnoses for bony tumors. This report highlights the aggressive nature and significant metastatic potential of the adenosquamous carcinoma.

Os tumores mamários são os mais comuns em cadelas e as metástases ósseas e pulmonares não são bem descritas. O carcinoma mamário adenoescamoso é um tumor raro que pode ser classificado como um tipo de tumor metaplásico. Este relato descreve os achados clínicos e histopatológicos dessa apresentação atípica de carcinoma mamário em um Poodle de 11 anos de idade, castrado. A cirurgia foi realizada para remover nódulos mamários malignos com diagnóstico provisório de carcinoma no exame citológico. Treze meses depois, a cadela retornou apresentando claudicação do membro pélvico esquerdo que persistia por seis meses antes da consulta. O paciente apresentava claudicação do membro pélvico direito e uma massa no mesmo membro. A radiografia do membro afetado revelou fratura patológica na diáfise femoral, proliferação do periósteo e áreas de osteopenia. Após estadiamento clínico, foi realizada amputação do membro pélvico esquerdo. O diagnóstico de carcinoma adenoescamoso mamário grau II foi feito através da histopatologia e imunohistoquímica. Embora incomuns, as metástases ósseas e pulmonares de tumores mamários, como o carcinoma adenoescamoso, podem ser consideradas diagnósticos diferenciais para tumores ósseos. Este relatório destaca a natureza agressiva e significativo potencial metastático do carcinoma adenoescamoso.

Diagnosis of canine rheumatoid arthritis / Diagnóstico da artrite reumatoide canina

Canine rheumatoid arthritis is a chronic inflammatory disease that affects the joints of dogs. The inflammation can cause damage to cartilage and bones and early diagnosis is the main factor determining treatment success. This report describes an unusual case of rheumatoid arthritis in a dog, highlighting the relevance of radiographic examination in association with histopathology in the definitive diagnosis. An 8 year old, male German Spitz dog, weighing 5kg was admitted with a history of cruciate ligament rupture and grade IV patella dislocation. Previously, surgery had been performed to correct the cranial cruciate ligament rupture, without success. On physical examination, the dog showed a palmigrade stance, severe pelvic limb lameness, and pain on palpation of all joints. Blood count and biochemical analysis were within normal ranges. Orthogonal radiographs of the joints of the pelvic and thoracic limbs were performed. The lesions were bilaterally symmetrical. Samples were taken from the patellofemoral joints for cytology, microbiology, and histopathologic analysis. Rheumatoid factor antibody assay was negative. In conclusion, the combination of more than one clinical sign and diagnostic tests, such as radiographs suggestive of rheumatoid arthritis, histopathologic analysis of the joints, and rheumatoid factor testing is required to reach a definitive diagnosis of rheumatoid arthritis.

A artrite reumatóide canina é por definição uma doença crônica inflamatória que acomete as articulações de cães. Como resultado, a artrite reumatoide pode causar lesões na cartilagem e nos ossos e o diagnóstico precoce é o principal fator para o sucesso do tratamento ideal. Este relato de caso objetivou descrever um caso incomum de artrite reumatóide em um cão, destacando a relevância do exame radiográfico associado à histopatologia no diagnóstico definitivo. Foi atendido um cão da raça Spitz Alemão, 8 anos, com 5kg de peso. Anteriormente, foi realizada procedimento cirúrgico para correção da ruptura bilateral de ligamento cruzado e luxação de patela grau IV, porém sem sucesso. Ao exame físico, o cão apresentava posição palmígrada, intensa claudicação dos membros pélvicos e sensibilidade dolorosa de todas as articulações à palpação. As análises de hemograma e bioquímica sérica básica estavam dentro dos limites normais. Foram realizadas radiografias ortogonais das articulações dos membros pélvicos e torácicos. A distribuição das lesões foi simétrica e em ambos os lados. Considerando esses achados, foram obtidas amostras biológicas das articulações para análise citológica, microbiológica e análise histopatológica. O anticorpo fator reumatóide também foi realizado e o resultado foi negativo. Diante do exposto, é necessária a associação de mais de um sinal clínico e diferentes exames, como por exemplo, radiografias sugestivas de artrite reumatóide, análise histopatológica das articulações e anticorpo fator reumatóide para alcançar o diagnóstico definitivo de artrite reumatóide.

Diagnosis of canine rheumatoid arthritis / Diagnóstico da artrite reumatoide canina

Canine rheumatoid arthritis is a chronic inflammatory disease that affects the joints of dogs. The inflammation can cause damage to cartilage and bones and early diagnosis is the main factor determining treatment success. This report describes an unusual case of rheumatoid arthritis in a dog, highlighting the relevance of radiographic examination in association with histopathology in the definitive diagnosis. An 8 year old, male German Spitz dog, weighing 5kg was admitted with a history of cruciate ligament rupture and grade IV patella dislocation. Previously, surgery had been performed to correct the cranial cruciate ligament rupture, without success. On physical examination, the dog showed a palmigrade stance, severe pelvic limb lameness, and pain on palpation of all joints. Blood count and biochemical analysis were within normal ranges. Orthogonal radiographs of the joints of the pelvic and thoracic limbs were performed. The lesions were bilaterally symmetrical. Samples were taken from the patellofemoral joints for cytology, microbiology, and histopathologic analysis. Rheumatoid factor antibody assay was negative. In conclusion, the combination of more than one clinical sign and diagnostic tests, such as radiographs suggestive of rheumatoid arthritis, histopathologic analysis of the joints, and rheumatoid factor testing is required to reach a definitive diagnosis of rheumatoid arthritis.(AU)

A artrite reumatóide canina é por definição uma doença crônica inflamatória que acomete as articulações de cães. Como resultado, a artrite reumatoide pode causar lesões na cartilagem e nos ossos e o diagnóstico precoce é o principal fator para o sucesso do tratamento ideal. Este relato de caso objetivou descrever um caso incomum de artrite reumatóide em um cão, destacando a relevância do exame radiográfico associado à histopatologia no diagnóstico definitivo. Foi atendido um cão da raça Spitz Alemão, 8 anos, com 5kg de peso. Anteriormente, foi realizada procedimento cirúrgico para correção da ruptura bilateral de ligamento cruzado e luxação de patela grau IV, porém sem sucesso. Ao exame físico, o cão apresentava posição palmígrada, intensa claudicação dos membros pélvicos e sensibilidade dolorosa de todas as articulações à palpação. As análises de hemograma e bioquímica sérica básica estavam dentro dos limites normais. Foram realizadas radiografias ortogonais das articulações dos membros pélvicos e torácicos. A distribuição das lesões foi simétrica e em ambos os lados. Considerando esses achados, foram obtidas amostras biológicas das articulações para análise citológica, microbiológica e análise histopatológica. O anticorpo fator reumatóide também foi realizado e o resultado foi negativo. Diante do exposto, é necessária a associação de mais de um sinal clínico e diferentes exames, como por exemplo, radiografias sugestivas de artrite reumatóide, análise histopatológica das articulações e anticorpo fator reumatóide para alcançar o diagnóstico definitivo de artrite reumatóide.(AU)

Metástase de adenocarcinoma em glândula apócrina em um cão / Metastatic apocrine gland adenocarcinoma in a dog

O adenocarcinoma de glândula apócrina raramente é relatado em cães, acometendo principalmente animais idosos e não tendo propensão entre machos ou fêmeas. Habitualmente, apresentam-se por nódulos únicos, podendo chegar até 10cm de diâmetro e, nos cães, os membros torácicos e pélvicos são os sítios de predileção. Geralmente, as neoplasias de glândulas apócrinas têm comportamento benigno, quando estas apresentam potencial maligno observam-se recidivas através de disseminação linfática e sanguínea. Relatou-se o caso de um cão macho, da raça Poodle, de 16 anos de idade, não castrado. A queixa principal referiu-se a uma lesão em orelha direita que apresentava secreção sanguinopurulenta há 30 dias, porém, ao exame físico, foi observado pequena massa no membro torácico direito, juntamente com linfonodo subescapular direito reativo. Foi colhido material de ambos os locais para exame citológico, o qual teve um resultado inconclusivo. Foi realizada nodulectomia em membro torácico direito, linfadenectomia subescapular e nodulectomia auricular. O material foi enviado para análise histopatológica. O diagnóstico foi de adenocarcinoma de glândula apócrina em membro torácico com metástase para linfonodo pré-escapular e de epitelioma sebáceo na lesão auricular. A tutora não aderiu ao protocolo quimioterápico proposto e o paciente veio a óbito após 30 dias do procedimento cirúrgico.

The apocrine gland adenocarcinoma is rarely reported in dogs, common in dogs and having no sex predisposition. They usually present a single lump reaching up 10 cm in diameter. In dogs, the thoracic and pelvic limbs are the common sites. Generally, the apocrine gland neoplasms have a benign behavior; metastasis can occur through lymphatic and blood dissemination when they are malignant. We report the case of a 16-year-old, uncastrated, male Poodle dog. The client reported a lesion in the right ear that had purulent and bloody discharge for 30 days, however, on physical examination, a small mass was observed in the right thoracic limb together with a reactive right subscapular lymph node. Samples were collected from both sites for cytological examination, which had an inconclusive result. Nodulectomy was performed on the right thoracic limb, subscapular lyphadenectomy and auricular nodulectomy. The histopathological analysis revealed an apocrine gland adenocarcinoma in the thoracic limb with metastasis to the cervical lymph node and sebaceous epithelioma in the auricular lesion. The client refused the chemotherapy protocol proposed and, the patient died 30 days after the surgical procedure.

Utrophin, MHC and M1/M2 macrophages in GRMD dogs / Utrofina, MHC e macrófagos M1 e M2 em cães DMGR

Muscular dystrophies are hereditary diseases that lead to progressive degeneration of the skeletal musculature. Golden Retriever dogs are used as animal models because they show a hereditary muscle disease similar to muscular dystrophy in humans. Aims: To evaluate the immunostaining of M1 (CD68) and M2 (CD163) macrophages, MHC I, MHC II and, utrophin in muscles of Golden Retriever dogs affected by muscular dystrophy (GRMD). Methods: Samples from 17 male dogs affected by GRMD were divided into GI - dystrophic dogs up to one year of age; and GII - dystrophic dogs over one-year-old. Results: Immunostaining of CD163 was higher than CD68 in both GI and GII. CD68 showed no variation between groups of dystrophic animals. MHC class I immunostaining was most evident in the biceps femoris and triceps brachialis. MHC class II was expressed mildly in four dystrophic muscle types in GI and GII. Utrophin immunostaining was higher in GII. Conclusion: M2 macrophages were one of the main mononuclear inflammatory cells found in dystrophic muscles. The number of M2 in muscles of dogs with GRMD increases with age, linking this cell subtype to permanent muscle damage.

As distrofias musculares são doenças hereditárias que levam à degeneração progressiva da musculatura esquelética. Cães Golden Retriever são usados como modelos animais, pois desenvolvem uma doença muscular hereditária semelhante à distrofia muscular em humanos. Objetivos: Avaliar a imunomarcação dos macrófagos M1 (CD68) e M2 (CD163), MHC I, MHC II e utrofina nos músculos de cães Golden Retriever afetados pela distrofia muscular (DMGR). Métodos: Amostras de 17 cães machos afetados por DMGR foram divididas em cães distróficos GI - até um ano de idade; e GII - cães distróficos com mais de um ano de idade. Resultados: a imunomarcação de CD163 foi maior que CD68 nos grupos GI e GII. CD68 não mostrou variação entre os grupos de animais distróficos. A imunomarcação de MHC classe I foi mais evidente no bíceps femoral e tríceps braquial. O MHC classe II foi expresso discretamente nos quatro tipos de músculo distrófico no GI e GII. A imunomarcação de utrofina foi maior no GII. Conclusão: Os macrófagos M2 foram uma das principais células inflamatórias mononucleares encontradas nos músculos distróficos. O número de M2 nos músculos de cães com DMGR aumentou com a idade, ligando esse subtipo de célula a danos musculares permanentes.

Utrophin, MHC and M1/M2 macrophages in GRMD dogs / Utrofina, MHC e macrófagos M1 e M2 em cães DMGR

Muscular dystrophies are hereditary diseases that lead to progressive degeneration of the skeletal musculature. Golden Retriever dogs are used as animal models because they show a hereditary muscle disease similar to muscular dystrophy in humans. Aims: To evaluate the immunostaining of M1 (CD68) and M2 (CD163) macrophages, MHC I, MHC II and, utrophin in muscles of Golden Retriever dogs affected by muscular dystrophy (GRMD). Methods: Samples from 17 male dogs affected by GRMD were divided into GI - dystrophic dogs up to one year of age; and GII - dystrophic dogs over one-year-old. Results: Immunostaining of CD163 was higher than CD68 in both GI and GII. CD68 showed no variation between groups of dystrophic animals. MHC class I immunostaining was most evident in the biceps femoris and triceps brachialis. MHC class II was expressed mildly in four dystrophic muscle types in GI and GII. Utrophin immunostaining was higher in GII. Conclusion: M2 macrophages were one of the main mononuclear inflammatory cells found in dystrophic muscles. The number of M2 in muscles of dogs with GRMD increases with age, linking this cell subtype to permanent muscle damage.(AU)

As distrofias musculares são doenças hereditárias que levam à degeneração progressiva da musculatura esquelética. Cães Golden Retriever são usados como modelos animais, pois desenvolvem uma doença muscular hereditária semelhante à distrofia muscular em humanos. Objetivos: Avaliar a imunomarcação dos macrófagos M1 (CD68) e M2 (CD163), MHC I, MHC II e utrofina nos músculos de cães Golden Retriever afetados pela distrofia muscular (DMGR). Métodos: Amostras de 17 cães machos afetados por DMGR foram divididas em cães distróficos GI - até um ano de idade; e GII - cães distróficos com mais de um ano de idade. Resultados: a imunomarcação de CD163 foi maior que CD68 nos grupos GI e GII. CD68 não mostrou variação entre os grupos de animais distróficos. A imunomarcação de MHC classe I foi mais evidente no bíceps femoral e tríceps braquial. O MHC classe II foi expresso discretamente nos quatro tipos de músculo distrófico no GI e GII. A imunomarcação de utrofina foi maior no GII. Conclusão: Os macrófagos M2 foram uma das principais células inflamatórias mononucleares encontradas nos músculos distróficos. O número de M2 nos músculos de cães com DMGR aumentou com a idade, ligando esse subtipo de célula a danos musculares permanentes.(AU)

Microambiente tumoral nas neoplasias mamárias em cadelas Revisão de literatura / Tumor microenvironment in canine mammary tumors - Literature review

Nos últimos anos, o microambiente tumoral foi associado à evolução de doenças crônicas, incluindo as neoplasias mamárias. Um crescente conjunto de evidências foi compilado para demonstrar o papel importante deste processo envolvendo as neoplasias mamárias caninas. A maneira pela qual as interações entre o tumor e o estroma participam ativamente do desenvolvimento neoplásico deve ser elucidada. Apesar de desempenhar função de contribuição na oncogênese, ainda não sabemos se este é um efeito direto ou indireto. A seguinte revisão descreve e esclarece algumas das principais evidências para a interação com o estroma tumoral e a evolução da progressão neoplásica.(AU)

In the recent years, the tumor microenvironment has been associated with the evolution of chronic diseases, including the mammary tumors. The evidence was compiled to demonstrate the important role of this process involving the canine mammary tumors. The way that the interactions between the tumor and the stroma actively participate in tumors development must be elucidated. Despite playing a role of contribution in the oncogenesis, we still do not know if this is a direct or indirect effect. The following review describes and clarifies some of the key evidence for the role of the interaction with the tumor stroma and the evolution of neoplastic progression.(AU)

Microambiente tumoral nas neoplasias mamárias em cadelas – Revisão de literatura / Tumor microenvironment in canine mammary tumors - Literature review

Nos últimos anos, o microambiente tumoral foi associado à evolução de doenças crônicas, incluindo as neoplasias mamárias. Um crescente conjunto de evidências foi compilado para demonstrar o papel importante deste processo envolvendo as neoplasias mamárias caninas. A maneira pela qual as interações entre o tumor e o estroma participam ativamente do desenvolvimento neoplásico deve ser elucidada. Apesar de desempenhar função de contribuição na oncogênese, ainda não sabemos se este é um efeito direto ou indireto. A seguinte revisão descreve e esclarece algumas das principais evidências para a interação com o estroma tumoral e a evolução da progressão neoplásica.

In the recent years, the tumor microenvironment has been associated with the evolution of chronic diseases, including the mammary tumors. The evidence was compiled to demonstrate the important role of this process involving the canine mammary tumors. The way that the interactions between the tumor and the stroma actively participate in tumor’s development must be elucidated. Despite playing a role of contribution in the oncogenesis, we still do not know if this is a direct or indirect effect. The following review describes and clarifies some of the key evidence for the role of the interaction with the tumor stroma and the evolution of neoplastic progression.

Participação de macrófagos M1, M2, MHC e da utrofina na distrofia muscular progressiva de cães

O objetivo do trabalho foi caracterizar lesões musculares e estudar marcação de dois subtipos de macrófagos, M1 (CD68) e M2 (CD163) além de MHC I, MHC II e utrofina, nos músculos mais acometidos pela doença (masseter, diafragma, tríceps braquial e bíceps femoral) em cães distróficos de diferentes idades. Foram utilizadas amostras musculares de 17 cães Golden Retriever (GR) machos e três controles não distróficos e livres de anormalidades neuromusculares, distribuídos em dois grupos: GI ? animais distróficos até um ano de idade (n=9) e GII ? animais distróficos acima de um ano de idade (n=8). Lesões histopatológicas características foram identificadas e classificadas nos quatro músculos distróficos: hialinização, infiltrado inflamatório mononuclear, necrose, regeneração, atrofia e hipertrofia, calcificação distrófica, fibrose e infiltração adiposa. As lesões variaram em extensão e distribuição de acordo com os músculos e o animal. Resultados mostraram que a imunodetecção do CD163 foi maior que a marcação de CD68 nos dois grupos. CD68 não mostrou variação independente da idade dos animais. A imunodetecção de MHC I foi mais evidente no bíceps femoral e tríceps braquial, seguida de marcações moderadas no masseter e diafragma do grupo com idade superior a um ano de idade. MHC II expressou-se de maneira discreta nos quatro músculos distróficos de ambos os grupos. A imunomarcação de utrofina foi maior no grupo afetado com idade superior a um ano de idade. Conclui-se que os macrófagos M2 estão entre as principais células inflamatórias mononucleares presentes nas lesões em cães distróficos e que com a idade ocorre aumento moderado de M2 no músculo de cães Golden Retriever distróficos indicando a associação deste tipo celular com a cronicidade da lesão muscular nestes animais

The objective was to characterize the lesions and study the expression of two subtypes of macrophages, M1 (CD68) and M2 (CD163) beyond MHC I, MHC II and utrophin in the most affected muscles by the disease (masseter , diaphragm, triceps braquii and biceps femoris) in dystrophic dogs of different ages. Samples muscle of 17 male Golden Retriever dogs and three controls non dystrophic and free of neuromuscular diseases were classified into two groups: G I - dystrophic animals under one year (n = 9) and G II - dystrophic animals over one year (n = 8). Pathological features were identified and classified in four dystrophic muscles: hyalinization, inflammatory infiltration, necrosis, regeneration, hypertrophy and atrophy, dystrophic calcification, fibrosis and fat infiltration. These lesions varied in extent and distribution according to the muscles and the animal evaluated. The results showed that the CD163 immunostaining detected in GRMD dogs was greater than marking CD68 in both groups. CD68 did not vary regardless of the age of the animals. The immunohistochemical expression of MHC I was most evident in the biceps femoris and triceps braquii, followed by moderate staining in the masseter and diaphragm in the group aged over one year old. MHC II expressed discretely in the four dystrophic muscles of both groups. The immunohistochemical expression of utrophin was higher in the affected group aged less than one year old. We concluded that the macrophage M2 were the main mononuclear inflammatory cells present in the dystrophic lesions in dogs. With the age there is a moderate increase of M2 macrophage in dystrophic muscle Golden Retriever dogs indicating the association of this cell type with the chronicity of muscle damage in these animals