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.

Quimiodectoma em cão / Chemodectoma in a dog

Background: The chemodectoma is a rare neoplasm that originates from chemoreceptors located mainly in the aortic body,and carotid body and sinus, and responsible for detecting variations in blood pH, oxygen pressure and carbon dioxide. Dogsof brachiocephalic breeds and aged between 7 and 15 years have greater propensity. A neoplasm involves infiltrative growthin the vessels at the heart base, which leads to Congestive Heart Failure (CHF). The definitive diagnosis is performed byhistopathological and/or immunohistochemical examination. The aim was to report a case of chemiodectoma in a dog,showing the disease’s clinical characteristics.Case: A 13-year-old male undefined breed dog was examinated in the medical clinic of small animal of Veterinary Hospital,Federal Rural University of Pernambuco (UFRPE) with respiratory effort, hyporexia, and edema in face, cervical, ventralthorax and thoracic limbs, with thirty days evoluted. About physical examination, we observed cachexia, orthopneic position, cyanosis and edema with a positive Godet sign, as well as 8% dehydration degree. Thoracic auscultation presentedmixed dyspnea and muffled heart sounds. Chest radiography detected an radiopacity increase in pulmonary section andmetastatic neoplastic process associated with pleural and pericardial effusion. Fluid therapy with lactated ringer and posteriorthoracentesis in the right hemithorax region was performed for greater respiratory comfort for the patient. Hematologicalcount and biochemical profiles stated normochromic normocytic anemia, relative and absolute lymphopenia, thrombocytopenia, as well as increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The patient diedafter 12 hours when was submitted to necroscopic examination and histopathological evaluation. An infiltrative tumor ofcardiac base was observed invading the light of the right atrium, obstructing the venous return, as well as a large thrombus...

Quimiodectoma em cão / Chemodectoma in a dog

Background: The chemodectoma is a rare neoplasm that originates from chemoreceptors located mainly in the aortic body,and carotid body and sinus, and responsible for detecting variations in blood pH, oxygen pressure and carbon dioxide. Dogsof brachiocephalic breeds and aged between 7 and 15 years have greater propensity. A neoplasm involves infiltrative growthin the vessels at the heart base, which leads to Congestive Heart Failure (CHF). The definitive diagnosis is performed byhistopathological and/or immunohistochemical examination. The aim was to report a case of chemiodectoma in a dog,showing the diseases clinical characteristics.Case: A 13-year-old male undefined breed dog was examinated in the medical clinic of small animal of Veterinary Hospital,Federal Rural University of Pernambuco (UFRPE) with respiratory effort, hyporexia, and edema in face, cervical, ventralthorax and thoracic limbs, with thirty days evoluted. About physical examination, we observed cachexia, orthopneic position, cyanosis and edema with a positive Godet sign, as well as 8% dehydration degree. Thoracic auscultation presentedmixed dyspnea and muffled heart sounds. Chest radiography detected an radiopacity increase in pulmonary section andmetastatic neoplastic process associated with pleural and pericardial effusion. Fluid therapy with lactated ringer and posteriorthoracentesis in the right hemithorax region was performed for greater respiratory comfort for the patient. Hematologicalcount and biochemical profiles stated normochromic normocytic anemia, relative and absolute lymphopenia, thrombocytopenia, as well as increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The patient diedafter 12 hours when was submitted to necroscopic examination and histopathological evaluation. An infiltrative tumor ofcardiac base was observed invading the light of the right atrium, obstructing the venous return, as well as a large thrombus...(AU)

Hemangiossarcoma associado a quimiodectoma em cadela Pit Bull idosa / Hemangiosarcoma associated with chemodectoma in an old Pit Bull bitch

Background: The prevalence of neoplasms in domestic animals has been augmenting over the years. Hemangiosarcoma, which most frequently affects large breed dogs, is a neoplasm with high metastatic power and corresponds to 5% of malignant neoplasms. Chemodectoma, a neoplasm that can have malignant or benign behavior, is uncommon, corresponding to less than 8% of all cardiac tumors, and originates from cardiac chemoreceptor cells and involves mainly the aortic and carotid bodies. The aim of this study is to describe the case of an elderly Pit Bull dog with hepatic hemangiosarcoma and chemodectoma associated with four other different tumors: hemangioma, papilloma, mastocitoma and melanoma. Case: A 14-year-old female Pit Bull, castrated, was presented to Veterinary Clinic of the Federal University of Santa Catarina (UFSC), Curitibanos Campus, Brazil. The owner referred apathy, hyporexia, and increased abdominal volume for two weeks. Physical examination showed emaciation and abdominal effusion. Abdominocentesis was performed, three liters of serosanguineous fluid was drained and a sample was sent for analysis. Complementary tests were requested and showed mild hypoalbuminemia, normocytic normochromic anemia, and lymphopenia. The ultrasound examination revealed thickening of vessels and hepatomegaly, in addition to the presence of an oval structure containing hyperechogenic cavitations. Diagnostic exploratory laparotomy was indicated, but the owner refused. Drug therapy was prescribed in a palliative manner and, during the clinical follow-up period, two abdominocentesis procedures and one thoracentesis procedure were performed, both resulting in simple transudate. Finally, the patient developed severe apathy, edema in all limbs, and died at home. Necroscopic examination was done and revealed hemoperitoneum and hemothorax...

Hemangiossarcoma associado a quimiodectoma em cadela Pit Bull idosa / Hemangiosarcoma associated with chemodectoma in an old Pit Bull bitch

Background: The prevalence of neoplasms in domestic animals has been augmenting over the years. Hemangiosarcoma, which most frequently affects large breed dogs, is a neoplasm with high metastatic power and corresponds to 5% of malignant neoplasms. Chemodectoma, a neoplasm that can have malignant or benign behavior, is uncommon, corresponding to less than 8% of all cardiac tumors, and originates from cardiac chemoreceptor cells and involves mainly the aortic and carotid bodies. The aim of this study is to describe the case of an elderly Pit Bull dog with hepatic hemangiosarcoma and chemodectoma associated with four other different tumors: hemangioma, papilloma, mastocitoma and melanoma. Case: A 14-year-old female Pit Bull, castrated, was presented to Veterinary Clinic of the Federal University of Santa Catarina (UFSC), Curitibanos Campus, Brazil. The owner referred apathy, hyporexia, and increased abdominal volume for two weeks. Physical examination showed emaciation and abdominal effusion. Abdominocentesis was performed, three liters of serosanguineous fluid was drained and a sample was sent for analysis. Complementary tests were requested and showed mild hypoalbuminemia, normocytic normochromic anemia, and lymphopenia. The ultrasound examination revealed thickening of vessels and hepatomegaly, in addition to the presence of an oval structure containing hyperechogenic cavitations. Diagnostic exploratory laparotomy was indicated, but the owner refused. Drug therapy was prescribed in a palliative manner and, during the clinical follow-up period, two abdominocentesis procedures and one thoracentesis procedure were performed, both resulting in simple transudate. Finally, the patient developed severe apathy, edema in all limbs, and died at home. Necroscopic examination was done and revealed hemoperitoneum and hemothorax...(AU)

Paraganglioma de corpo aórtico em cão / Aortic body paraganglioma in dog

Background: Aortic body paragangliomas are uncommon neoplasms that develop mainly in aortic and carotid bodies. It has been supposed that genetic factors and chronic hypoxia may stimulate tumor development. The brachycephalic dog breeds, as Boxer, are most predisposed to present this neoplasm. The clinical symptomatology is related to tumor size and localization. Usually aortic body paraganglioma has benign biological behavior, when it is malignant, rarely promotes metastases. The aim of this study was to report a case of the aortic body paraganglioma as death cause in a dog. Case: A canine, 10-year-old, male, cross breed, presented clinical signs as anorexia, emesis, cough, dyspnea and exercise intolerance. After death the animal was examined at the Department of Veterinary Pathology at the Federal Rural University of Amazonia. On necropsy, no pericardial effusion was identified, however pleural and abdominal effusion was observed, volume like 1000 and 700 mL, respectively. The heart had a neoplasm near the left atrium, it measured 6.5 x 8.2 cm, had irregular surface, firm consistency, grayish color, and at the cut showed infiltration in the myocardium, as well as obstruction of the left atrial lumen and left ventricle concentric hypertrophy. No distant metastases were found. Microscopically, the tumor consisted of polyhedral morphology cells, eosinophilic cytoplasm, spherical and hyperchromatic nucleus. Cells were grouped into lobes separated by fibrovascular stroma, large cells (less uniform cells), low mitotic rate and myocardial infiltration. On immunohistochemical analysis anti-cytokeratin, anti-vimentin and anti-S-100 antibodies were used. Tumour cells stained was absent for anti-cytokeratin and anti-vimentin, but was anti-S-100 positive. A case of malignant aortic body paraganglioma grade II was diagnosed.[…](AU)

Paraganglioma de corpo aórtico em cão / Aortic body paraganglioma in dog

Background: Aortic body paragangliomas are uncommon neoplasms that develop mainly in aortic and carotid bodies. It has been supposed that genetic factors and chronic hypoxia may stimulate tumor development. The brachycephalic dog breeds, as Boxer, are most predisposed to present this neoplasm. The clinical symptomatology is related to tumor size and localization. Usually aortic body paraganglioma has benign biological behavior, when it is malignant, rarely promotes metastases. The aim of this study was to report a case of the aortic body paraganglioma as death cause in a dog. Case: A canine, 10-year-old, male, cross breed, presented clinical signs as anorexia, emesis, cough, dyspnea and exercise intolerance. After death the animal was examined at the Department of Veterinary Pathology at the Federal Rural University of Amazonia. On necropsy, no pericardial effusion was identified, however pleural and abdominal effusion was observed, volume like 1000 and 700 mL, respectively. The heart had a neoplasm near the left atrium, it measured 6.5 x 8.2 cm, had irregular surface, firm consistency, grayish color, and at the cut showed infiltration in the myocardium, as well as obstruction of the left atrial lumen and left ventricle concentric hypertrophy. No distant metastases were found. Microscopically, the tumor consisted of polyhedral morphology cells, eosinophilic cytoplasm, spherical and hyperchromatic nucleus. Cells were grouped into lobes separated by fibrovascular stroma, large cells (less uniform cells), low mitotic rate and myocardial infiltration. On immunohistochemical analysis anti-cytokeratin, anti-vimentin and anti-S-100 antibodies were used. Tumour cells stained was absent for anti-cytokeratin and anti-vimentin, but was anti-S-100 positive. A case of malignant aortic body paraganglioma grade II was diagnosed.[…]

CARACTERIZAÇÃO OFTALMOPATOLÓGICA DE NEOPLASMAS METASTÁTICOS EXTRAOCULARES OU MULTICÊNTRICOS EM CÃES E GATOS.

Este trabalho pretende caracterizar a frequência e a distribuição do acometimento ocular de cães e gatos mortos em decorrência de neoplasias metastáticas de origem extraocular ou multicêntricas por meio de exame de necropsia. Para tanto, os arquivos do Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul foram revisados e compilados de janeiro de 2015 a janeiro de 2019. A população amostral obtida foi de 333 animais, destes 233 eram cães e 100 gatos e 40 apresentaram metástase (s) ocular (es), o que correspondeu a 11,6% nos cães e a 13% nos gatos. O linfoma foi a neoplasia mais comumente diagnosticada em ambas as espécies. Nos cães, o linfoma difuso de grandes células B (DLBCL) (5/14), linfoma linfoblástico de células T (LBL) (4/14), linfoma de células T periféricas (PTCL) (3/14) e linfoma linfocítico B (2/14) acometeram os olhos de forma bilateral e predominantemente em úvea anterior. Nos gatos, o linfoma T associado ao Vírus da Leucemia Felina foi o mais frequente e com envolvimento majoritário do corpo ciliar. O carcinoma de glândula mamária em cadelas foi o segundo neoplasma que mais acometeu os olhos, com distribuição unilateral, multifocal e obliterante em vasos sanguíneos da úvea. Nos gatos, depois do linfoma, o carcinoma pulmonar e o carcinoma de células escamosas (CCE) foram os que mais acometeram o globo ocular. Carcinomatose meningeal em nervo óptico foi demonstrada em dois gatos com CCE e duas cadelas com carcinoma anaplásico mamário. Observou-se ainda metástases oculares de colangiocarcinoma, hemangiossarcoma e quimiodectoma nos cães, e de carcinoma cribriforme de glândula mamária, de carcinoma de glândula salivar mandibular e de sarcoma histiocítico disseminado nos gatos. Dado o exposto, o globo ocular em cães e gatos configurou sítio metastático ou multicêntrico em 12% dos animais deste estudo. Tanto em cães quanto em gatos, o linfoma e os carcinomas foram as neoplasias, com maior implicação ocular. No conhecimento dos autores, pela primeira vez são demonstradas metástases intraoculares de colangiocarcinoma e quimiodectoma em cães, bem como carcinoma de glândula salivar em gato.

This study aims to characterize the frequency and distribution of ocular involvement in dogs and cats who died due to metastatic neoplasms from extraocular or multicentric origin established through necropsy examination. Therefore, archives from the Setor de Patologia Veterinária of Universidade Federal do Rio Grande do Sul were revised and compiled from January 2015 to January 2019. The sampled population consisted of 333 animals, 233 dogs and 100 cats, 40 of which presented ocular metastasis, corresponding to 11,6% of dogs and 13% of cats. Lymphoma was the most commonly diagnosed neoplasia for both species. For dogs, diffuse large B-cell lymphoma (DLBCL) (5/14), lymphoblastic T-cell lymphoma (LBL) (4/14), peripheral T-cell lymphoma (PTCL) (3/14) and lymphocytic B cell lymphoma (2/14) involved the eyes bilaterally and predominantly in the anterior uvea. For cats, FeLV-associated T-cell lymphoma was the most frequent, involving mainly the ciliary body. Carcinoma of the mammary gland in bitches was the second most important neoplasm involving the eyes, distributed unilaterally, multifocally and obliterating blood vessels of the uvea. For cats, following lymphomas, pulmonary carcinoma and squamous cell carcinoma (SCC) were the most prevalent in the eyeball. Meningeal carcinomatosis in the optic nerve was demonstrated in two cats with SCC and two dogs with anaplastic carcinoma of the mammary gland. Additionally, ocular metastasis of cholangiocarcinoma, hemangiosarcoma and chemodectoma in dogs and cribriform carcinoma of the mammary gland, carcinoma of the mandibular salivary gland and disseminated histiocytic sarcoma in cats were observed. Given the above, the ocular globe of dogs and cats was demonstrated to be a site for metastasis or multicentric neoplasia in 12% of the studied animals. For both dogs and cats, lymphoma and carcinoma were the main neoplasia with major implication in the eye. To the authors knowledge, intraocular metastasis of cholangiocarcinoma and chemodectoma in dogs, and carcinoma of the mandibular salivary gland in cats were first reported in this study.

Prevalência e aspectos anatomopatológicos das neoplasias primárias do coração, de tecidos da base do coração e metastáticas, em cães do Sul de Minas Gerais (1994-2009) / Prevalence and anatomopathological findings of primary cardiac neoplasms of the heart base tissues and metastases in dogs from southern Minas Gerais, Brazil (1994-2009)

Este estudo teve como objetivo determinar a prevalência e achados anatomopatológicos de tumores primários e metastáticos do coração ou de tecidos da base do coração, diagnosticados em caninos do Sul de Minas Gerais. O diagnóstico foi realizado mediante análise histopatológica e imuno-histoquímica das neoplasias. Durante os anos de 1994-2009, foram realizadas 2397 necropsias em caninos. Neoplasias no coração foram detectadas em 31 cães (1,29%), onde, sete (22,58%) eram primárias e 24 (77,42%) metastáticas. As neoplasias diagnosticadas como primárias do coração foram o hemangiossarcoma (1/7) e o mixoma (1/7); e como primárias da base do coração o quimiodectoma (3/7) e o carcinoma de tireoide ectópica (2/7). A frequência foi maior em cães machos (5/7), da raça Boxer (3/7) e com idade média de 9,7±1,88 anos. Nas neoplasias metastáticas, a frequência foi maior em fêmeas (15/24), em cães da raça Rottweiler (7/24) e a idade média foi de 7,5±3,23 anos, sendo o linfoma de células T a neoplasia metastática de maior ocorrência (7/27).(AU)

The purpose of this study was to determine the prevalence and anatomopathological findings of primary and metastatic heart tumors and from heart base tumors diagnosed in dogs from southern Minas Gerais, Brazil. The diagnosis was based on histological characteristics and immunophenotyping of the tumors cells. From 1994 to 2009, 2397 necropsies of dogs were performed. Cardiac neoplasms were diagnosed in 31 dogs (1.29%), where seven (22.58%) were primary and 24 (77.42%) were metastatic. Neoplasms of the heart diagnosed as primary were hemangiosarcoma (1/7) and myxoma (1/7), and, primary of heart base, the chemodectoma (3/7) and ectopic thyroid carcinoma (2/7). Frequency was higher in male dogs (5/7), of Boxer breed (3/7) with mean age of 9.7±1.88 years. In metastatic neoplasms, the frequency was higher in female dogs (15/24), of Rottweiler breed (7/24) with the mean age of 7.5±3.23 years. The T cell lymphoma (7/27) was the most frequent neoplasm, diagnosed as metastatic.(AU)

Quimiodectoma em equino: relato de caso / Chemodectoma in equine: case report / Quimiodectoma en equina: presentación de un caso

O quimiodectoma corresponde à neoplasia dos quimiorreceptores periféricos que detectam alterações de pH, temperatura e pressões parciais de O2 e CO2 na corrente sanguínea. A partir desta detecção, esses transmitem impulsos nervosos para os centros cerebrais respiratórios e cardíacos para promoção da homeostase, através do sistema nervoso autônomo. Em levantamento bibliográfico há relato de apenas dois casos em equinos, um no corpo aórtico de uma fêmea de 5 anos e em um macho castrado de 13 anos de idade. O objetivo do presente trabalho é relatar um caso de quimiodectoma em equino diagnosticado em necropsia no Hospital Veterinário de Uberaba.(AU)

The chemodectoma corresponds to the peripheral chemoreceptors neoplasia which detect changes in pH, temperature and partial pressures of 02 and C02 in the bloodstream. From this detection, these transmit nerve impulses to the brain respiratory and cardiac centers to promote homeostasis, through the autonomic nervous system. In literature there are reports of only two cases in horses, one in aortic body of a female of 5 years and in a castrated male 13 years old. The aim of this study is to report a case of chemodectomaequinus diagnosed at autopsy at the Veterinary Hospital of Uberaba.(AU)

El quimiodectoma corresponde a la neoplasia de los quimiorreceptores periféricos que detectan alteraciones de pH, temperatura y presiones parciales de O2 y CO2 en la corrí ente sanguínea. A partir de esta detección, estos transmiten impulsos nerviosos para los centros cerebrales, respiratorios y cardíacos para promoción de la homeostase, através del sistema nervioso autónomo. En el levantamiento bibliográfico, hay relatos de apenas dos casos en equinos, uno en el cuerpo aórtico de una hembra de 5 anos yotro en un macho castrado de 13 anos de edad. El objetivo del presente trabajo es relatar un caso de quimiodectoma en equino diagnosticado en necropsia en el Hospital Veterinário de Uberaba.(AU)

Quimiodectoma em equino: relato de caso / Chemodectoma in equine: case report / Quimiodectoma en equina: presentación de un caso

O quimiodectoma corresponde à neoplasia dos quimiorreceptores periféricos que detectam alterações de pH, temperatura e pressões parciais de O2 e CO2 na corrente sanguínea. A partir desta detecção, esses transmitem impulsos nervosos para os centros cerebrais respiratórios e cardíacos para promoção da homeostase, através do sistema nervoso autônomo. Em levantamento bibliográfico há relato de apenas dois casos em equinos, um no corpo aórtico de uma fêmea de 5 anos e em um macho castrado de 13 anos de idade. O objetivo do presente trabalho é relatar um caso de quimiodectoma em equino diagnosticado em necropsia no Hospital Veterinário de Uberaba.

The chemodectoma corresponds to the peripheral chemoreceptors neoplasia which detect changes in pH, temperature and partial pressures of 02 and C02 in the bloodstream. From this detection, these transmit nerve impulses to the brain respiratory and cardiac centers to promote homeostasis, through the autonomic nervous system. In literature there are reports of only two cases in horses, one in aortic body of a female of 5 years and in a castrated male 13 years old. The aim of this study is to report a case of chemodectomaequinus diagnosed at autopsy at the Veterinary Hospital of Uberaba.

El quimiodectoma corresponde a la neoplasia de los quimiorreceptores periféricos que detectan alteraciones de pH, temperatura y presiones parciales de O2 y CO2 en la corrí ente sanguínea. A partir de esta detección, estos transmiten impulsos nerviosos para los centros cerebrales, respiratorios y cardíacos para promoción de la homeostase, através del sistema nervioso autónomo. En el levantamiento bibliográfico, hay relatos de apenas dos casos en equinos, uno en el cuerpo aórtico de una hembra de 5 anos yotro en un macho castrado de 13 anos de edad. El objetivo del presente trabajo es relatar un caso de quimiodectoma en equino diagnosticado en necropsia en el Hospital Veterinário de Uberaba.

Fibrilação atrial em cão associada ao quimiodectoma infiltrativo atrial: relato de caso / Atrial fibrillation in dog associated with an infiltrative chemodectoma in the atrial myocardium: a case report

Relata-se o caso de um cão, sem raça definida, levado ao veterinário por apresentar cansaço fácil e episódios de síncope. Foram identificadas fibrilação atrial e extra-sístoles ventriculares isoladas ao exame eletrocardiográfico. O tratamento antiarrítmico não foi eficaz, e o animal morreu devido a um episódio de síncope. À necropsia, observou-se massa em região de base cardíaca, invadindo a luz do átrio esquerdo. Histologicamente, constatou-se a presença de quimiodectoma. A infiltração miocárdica atrial causou lesões nos miócitos, produzindo circuitos reentrantes e/ou focos ectópicos de despolarização atrial.(AU)

This case reports a mongrel dog referred to a veterinarian due to tiredness and syncope episodes. Atrial fibrillation and ventricular premature complex were observed during electrocardiographic exam. The anti-arrhythmic treatment was not effective and the dog died from syncope. At necropsy, a mass invading the internal area of the left atrium was evidenced in the base of the heart. The occurrence of chemodectoma was histologically exhibited. Infiltrations in the atrial myocardium caused alterations in the miocites and produced reentrant circuits and/or atrial depolarization ectopic points.(AU)

Chemodectoma in dogs: a case report / Quemodectoma em cães: relato de caso

Chemodectoma is a neoplasm arising from the carotid and aortic bodies, having neuroectodermic origin. It has been related mainly in human beings and dogs. Among the later, the brachiocephalics are the most susceptible, mainly the ones older than six. This case reports a seven year old, male Boxer dog, presenting convulsion and dry cough. The animal died and it was sent to the Pathological Anatomy Section of the Department of Pathology at FMVZ-USP. The post-mort examination revealed the presence of hemopericardium, pulmonar oedema, hepatic and renal congestion and gall bladder oedema, but the most important feature found was the presence of 4 oviform tumoral masses, within the toracic cavity. The histopathology revealed a solid tissue, essentially cellular, with lobules delimitated by delicate septa arising from bands of thick connective tissue. The neoplastic cells presented an homogeneous aspect characterized by a round or polyhedral shape with an excentric and evident nucleoli. There were few mitosis, without atypical signes. The micro and macroscopics aspects are compatible with a chemodectoma diagnosis.

O quemodectoma é uma neoplasia derivada dos corpos aórticos e carotídeos, tendo origem neuroectodérmica. Tem sido relatado com maior freqüência em humanos e cães. Destes, os animais braquicefálicos são os mais susceptíveis, notadamente em faixa etária superior a 6 anos. O presente relato se refere a um animal de espécie canina, de raça Boxer, macho, de 7 anos de idade, apresentando histórico de quadro convulsivo e tosse seca. O animal veio a óbito e foi encaminhado ao setor de Anatomia Patológica do Departamento de Patologia da FMVZ-USP. O exame macroscópico evidenciou a presença de hemopericárdio, congestão e edema pulmonares, congestão hepática, renal e edema de vesícula biliar. Porém, o achado macroscópico mais significativo foi a presença de 4 formações tumorais ovaladas na cavidade torácica. O exame histopatológico das formações evidenciou um tecido sólido, altamente celular, com a delimitação de lóbulos através de trabéculas conjuntivas espessas, que emitiam septos delicados subdividindo-os. As células tumorais apresentaram-se uniformes, tendo um formato poliédrico, com núcleo grande esférico, geralmente excêntrico; nucléolo evidente, e cromatina finamente granular; citoplasma de dimensões variáveis e granulação acidofílica delicada. Foi observado pequeno número de figuras mitóticas sem sinais de atipia. Os quadros macro e microscópicos são compatíveis com o diagnóstico d

Quimiodectoma de corpo carotídeo em cão: relato de caso / Carotid body chemodectoma in dog: case report

Quimiodectomas de corpo carotídeo são tumores raros e de interesse na clínica veterinária, devido ao seu modo de apresentação e desafio em relação a abordagem clínica e cirúrgica. Desenvolvem-se como aumento de volume no pescoço, que normalmente é diagnosticado quando se faz necessária a resseção cirúrgica. Descreve-se o caso de cão da raça Beagle de 10 anos de idade, atendido no Hospital Veterinário Clinivet, na cidade de Curitiba- PR, com aumento de volume em região ventro-lateral direita do pescoço, de forma nodular, medindo em torno de 7 centímetros de diâmetro, de consistência firme e aderido ao tecido muscular. Ao exame clínico e físico não foi notado por à palpação, observou-se um aumento discreto dos linfonodos poplíteos e demais parâmetros sem alteração. Radiografias torácicas e cervicais revelaram desvio lateral da traquéia em região cervical para a esquerda, causado por massa de radiopacidade de tecidos moles. A área pulmonar mostrou-se sem alterações, assim como a silhueta cardíaca. Hemograma demonstrou discreta linfopenia. Foi preconizado a biópsia para a coleta de fragmento e o exame histopatológico concluiu ser quimiodectoma de corpo carotídeo. O paciente foi medicado com doses diárias de prednisona. Este sobreviveu durante dois anos e nove meses sem alterações em relação ao tamanho do tumor. Porém, devido ao avançado da idade, o proprietário optou pela eutanásia. Foi permitida a realização da necropsia e constatou-se redução acentuada da massa neoplásica cervical, que mediu cerca de 2 centímetros de diâmetro, de características calcificadas em seu interior. Nos demais órgãos não se observaram alterações significantes. Embora a resseção cirúrgica do quimiodectoma de corpo carotídeo tenha resultados satisfatórios conforme a literatura, a morbidade ainda é um problema significante e pode debilitar o paciente(AU)

Carotid body chemodectoma are rare tumors which have veterinary clinical interest due to their way of presentation and to the challenge they mean in relation to clinical and surgical approach. They develop as an increasing volume on the neck and are usually diagnosed when surgical resection is necessary. A 10-year-old Beagle dog, presented to the Clinivet Veterinary Hospital in Curitiba city, with an increasing volume on the ventro-lateral area of the neck, with nodular form, measuring around 7 centimeters of diameter, firm consistence and adhered to muscular tissue. During the clinical and physical examinations, no pain was noted on palpation. Popliteal lymphonodus was slightly increased and did not present alterations in other parameters. Thoracic and cervical radiographs revealed lateral deviation of the trachea in the cervical area to the left, caused by a radiopaque mass of soft tissue. Pulmonary area did not show alterations, and neither the cardiac silhouette. Hemogram demonstrated lymphopenia. Biopsy to collect a fragment was preconized and the histopathological exam concluded to be a carotid body chemodectoma. Medication with diary doses of prednisone was done. This patient survived during 2 years and 9 months without alterations of the tumor size. However, due to its advanced age, the owner made a choice for the euthanasia. Necropsy was consented and a pronounced reduction of the cervical neoplastic mass was evidenced, which measured about 2 centimeters of diameter, with calcified characteristics inside. In other organs, no significant alterations were observed. Although the surgical resection of the carotid body chemodectoma usually presents satisfactory results in accordance to the literature, morbidity is still a significant problem and can debilitate to the patient(AU)

Quimiodectoma de corpo carotídeo em cão: relato de caso / Carotid body chemodectoma in dog: case report

Quimiodectomas de corpo carotídeo são tumores raros e de interesse na clínica veterinária, devido ao seu modo de apresentação e desafio em relação a abordagem clínica e cirúrgica. Desenvolvem-se como aumento de volume no pescoço, que normalmente é diagnosticado quando se faz necessária a resseção cirúrgica. Descreve-se o caso de cão da raça Beagle de 10 anos de idade, atendido no Hospital Veterinário Clinivet, na cidade de Curitiba- PR, com aumento de volume em região ventro-lateral direita do pescoço, de forma nodular, medindo em torno de 7 centímetros de diâmetro, de consistência firme e aderido ao tecido muscular. Ao exame clínico e físico não foi notado por à palpação, observou-se um aumento discreto dos linfonodos poplíteos e demais parâmetros sem alteração. Radiografias torácicas e cervicais revelaram desvio lateral da traquéia em região cervical para a esquerda, causado por massa de radiopacidade de tecidos moles. A área pulmonar mostrou-se sem alterações, assim como a silhueta cardíaca. Hemograma demonstrou discreta linfopenia. Foi preconizado a biópsia para a coleta de fragmento e o exame histopatológico concluiu ser quimiodectoma de corpo carotídeo. O paciente foi medicado com doses diárias de prednisona. Este sobreviveu durante dois anos e nove meses sem alterações em relação ao tamanho do tumor. Porém, devido ao avançado da idade, o proprietário optou pela eutanásia. Foi permitida a realização da necropsia e constatou-se redução acentuada da massa neoplásica cervical, que mediu cerca de 2 centímetros de diâmetro, de características calcificadas em seu interior. Nos demais órgãos não se observaram alterações significantes. Embora a resseção cirúrgica do quimiodectoma de corpo carotídeo tenha resultados satisfatórios conforme a literatura, a morbidade ainda é um problema significante e pode debilitar o paciente

Carotid body chemodectoma are rare tumors which have veterinary clinical interest due to their way of presentation and to the challenge they mean in relation to clinical and surgical approach. They develop as an increasing volume on the neck and are usually diagnosed when surgical resection is necessary. A 10-year-old Beagle dog, presented to the Clinivet Veterinary Hospital in Curitiba city, with an increasing volume on the ventro-lateral area of the neck, with nodular form, measuring around 7 centimeters of diameter, firm consistence and adhered to muscular tissue. During the clinical and physical examinations, no pain was noted on palpation. Popliteal lymphonodus was slightly increased and did not present alterations in other parameters. Thoracic and cervical radiographs revealed lateral deviation of the trachea in the cervical area to the left, caused by a radiopaque mass of soft tissue. Pulmonary area did not show alterations, and neither the cardiac silhouette. Hemogram demonstrated lymphopenia. Biopsy to collect a fragment was preconized and the histopathological exam concluded to be a carotid body chemodectoma. Medication with diary doses of prednisone was done. This patient survived during 2 years and 9 months without alterations of the tumor size. However, due to its advanced age, the owner made a choice for the euthanasia. Necropsy was consented and a pronounced reduction of the cervical neoplastic mass was evidenced, which measured about 2 centimeters of diameter, with calcified characteristics inside. In other organs, no significant alterations were observed. Although the surgical resection of the carotid body chemodectoma usually presents satisfactory results in accordance to the literature, morbidity is still a significant problem and can debilitate to the patient