Mesotelioma pleural em mediastino em uma cadela - remoção com esternotomia mediana / Mediastinal mesothelioma in a bitch - removal with median sternotomy

Background: Malignant pleural mesothelioma (MPM) is a neoplasm with low incidence in small animals, and the possible causes are poorly elucidated but may be related to contact with asbestos. In the thoracic cavity, MMP can be localized or generalized to all cavity structures, and its clinical signs depend on this localization. Although some alternative therapies are being discussed, few studies are conclusive, with surgical intervention as the leading therapeutic option. Given this context, this report aimed to describe a case of MMP located in the mediastinum of a bitch treated with radical excision through mediated sternotomy. Case: A 7-year-old bitch of the Shar-pei breed was referred for care due to progressive weight loss and intense dyspnea. During the physical examination, dyspnea and muffled lung sounds were noted. The patient underwent hemodialysis, which showed neutrophilic leukocytosis. An abdominal ultrasound was also performed and revealed mild abdominal effusion, and chest radiography revealed an extensive tumor covering the entire chest cavity. Thoracocentesis was performed, and the material analyzed was a malignant exudate; the patient was referred to median sternotomy for exploratory purposes, and afterward, total macroscopic extirpation of the tumor was performed. A sample was sent for histopathology, and malignant mesothelioma was confirmed. The patient was discharged after 8 days of hospitalization with home treatment and did not return to the hospital. Upon contacting the guardian, we were informed that the animal had died 154 days after the procedure due to unknown causes. Discussion: Malignant pleural mesothelioma affects humans and animals; it is associated with the risk factor of contact with asbestos and the use of flea antiparasitic drugs. In small animals, its incidence is rare, albeit mesotheliomas have been reported in wild and large animals. The clinical signs are related to the location of the neoplasm. When it is located in the thoracic region, dyspnea, muffled lung sounds, cyanosis, and pleural effusion are observed in most cases. Diagnosis is usually late and incidental, although some tests, such as ultrasonography, magnetic resonance imaging, tomography, radiography, and needle biopsy, can help in the diagnosis. Histopathology is the exam of choice for definitive diagnosis, as it helps one observe the proliferation of neoplastic mesothelial cells, atypical mitosis figures, and marked cellular pleomorphism. Many therapeutic options have been discussed, including chemotherapy, immunotherapy, and anti-tumor immunization, although there is little scientific proof of their efficacy in animals. The current treatment of choice is tumor excision by surgical procedure with a palliative objective since the prognosis of the disease is unfavorable. Minimally invasive video surgery has been gaining more and more space in veterinary medicine and has proven successful in numerous cases of thoracic masses. In the present report, we chose to perform median sternotomy for total excision due to the extension of the mass that occupied the thoracic cavity practically in its entirety. Further research should be conducted to help in palliative treatments and increase the survival of patients with mesotheliomas, given that most studies are done in humans and not animals. We conclude that median sternotomy is still the therapeutic option of choice for the palliative treatment of patients with extensive thoracic pleural mesotheliomas.

Linfoma mediastinal em gato com vírus da leucemia felina / Mediastinal lymphoma in a cat with feline leukemia virus

Background: Mediastinal lymphoma occurs at a high incidence in cats positive for feline leukemia virus (FeLV). It is a malignant lymphocytic neoplasm that may trigger clinical signs such as dyspnea, apathy, regurgitation, and weight loss. The objective of this work is to report a case of mediastinal lymphoma associated with FeLV in a cat, and describe the clinical, pathological, diagnostic, and therapeutic aspects that can help the diagnosis and treatment of this disease. Case: A 3-year-old male neutered cat weighing 4.6 kg, positive for FeLV, and with a history of dyspnea and hyporexia was referred to a private veterinary clinic in the city of Caxias do Sul, RS, Brazil. The only alteration found at the clinical examination was a muffled sound during lung auscultation. Radiographs of the thorax revealed the presence of pleural effusion; after drainage of the fluid, a mass located in the mediastinal area became radiographically observable. An analysis of the effusion fluid showed high cellularity characterized by a markedly pleomorphic population of individual round cells consistent with lymphocytes. Small lymphocytes with a high nucleus:cytoplasm ratio, round nucleus, condensed chromatin, and inconspicuous nucleoli were observed, along with medium and large lymphocytes. The medium and large lymphocytes were characterized by a variably increased nucleus:cytoplasm ratio and a scant to moderate cytoplasm exhibiting moderate to intense basophilia and, occasionally, vacuoles. The nuclei were round, idented, or irregular; most of them were located eccentrically and contained coarse to finely granular chromatin. Nucleoli varied from single to multiple, round to angular, and central to peripheral and prominent. Macronucleoli and marked anisonucleosis were also observed, as well as binucleated cells and rare multinucleated cells. The conclusion was that it was a case of neoplastic effusion caused by a lymphoma. After an appointment with an oncologist, a chemotherapy protocol was established. The treatment of choice was CHOP, a combination of cyclophosphamide (20 mg/kg orally), doxorubicin (1 mg/kg intravenously), vincristine (0.5 mg/m2 intravenously), and prednisolone with a regressive dose starting at 2 mg/kg. The patient underwent 4 rounds of chemotherapy, and received a maintenance treatment thereafter. The patient's condition remained stable for 390 days without relevant clinical or hematological alterations. Discussion: The diagnosis of mediastinal lymphoma was established by associating clinical finings, laboratory exams, and radiographic findings. Exams of utmost importance to reach this diagnosis were the thoracic radiography, which revealed the presence of a mass in the thorax, and the cytopathological analysis of the effusion fluid, as round cell neoplasms are easily dissociated. Young cats are the group most affected by FeLV, and mediastinal lymphoma is considered the most prevalent type of lymphoma in this species. The most common clinical sign is dyspnea; however, other signs such as apathy, weight loss, regurgitation (due to pressure on the esophagus), and Horner's syndrome (owing to pressure on the thoracic sympathetic innervation) may also occur. This disease is treated with chemotherapy, with CHOP frequently used as the chemotherapeutic protocol. The good therapeutic response for a longer time than the average estimated by studies on the prognostic of this disease indicates that a correct diagnosis along with an assertive approach and the cooperation of the tutor are essential in cases of mediastinal lymphoma.

Mediastinal extraskeletal osteosarcoma in a canine with pulmonary and cerebral metastasis

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

Mediastinal extraskeletal osteosarcoma in a canine with pulmonary and cerebral metastasis

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

Hipercalcemia humoral maligna secundária a linfoma mediastinal em cães / Malignant humoral hypercalcemia secondary to mediastinal lymphoma in dogs / Hipercalcemia humoral maligna secundaria a linfoma mediastinal en perros

Hipercalcemia é o aumento de cálcio total ou ionizado na corrente sanguínea e é um marcador para algumas doenças como as neoplasias malignas. Quando ocorre o aumento de cálcio secundário a neoplasias, ele se caracteriza como uma síndrome paraneoplásica. Dentre as neoplasias malignas que causam a hipercalcemia, o linfoma aparece em grande porcentagem dos achados clínicos, sendo o linfoma mediastinal o que é mais associado com a hipercalcemia gerando a hipercalcemia humoral maligna. O linfoma mediastinal é associado à produção de células T por envolver o timo e atinge os linfonodos mediastinais. Através da produção de células neoplásicas ocorre o aumento de cálcio no organismo que é resultado da ligação de proteína relacionada ao paratormônio (PTHrP) aos receptores de paratormônio (PTH) causando reabsorção óssea e por síntese de outras substâncias que agem como ativadores de osteoclastos. A melhor forma de combate a hipercalcemia humoral maligna é o uso de protocolos de quimioterapia. É indicado realização de suporte para o excesso de cálcio no organismo, pois o mesmo causa alterações fisiologicamente indesejáveis.(AU)

Hypercalcemia is the high total or ionized calcium in the circulatory system and it is a marker for some diseases such as malignant neoplasms. When neoplastic secondary high calcium occurs, it characterizes as a paraneoplastic syndrome. Among malignant neoplasms that cause hypercalcemia Iynphoma appears in a huge porcent of clinical findigns, which mediastinal Iymphoma is the most hypercalcemia associated generating the malignant humoural hypercalcemia. Mediastinallymphoma is associated with the production of T cells by envolving thymus and reaches the mediastinallymphs. Throughout the production of neoplastic cells high cálcio in the organismo occurs, which is a result of the linkage of the protein related to parathyroid hormone (PTH) with the parathyroid hormone receptor (PTH) causing bone resorption and by the synthesis of other substances that work as osteoclast activators. The best way to fight malignant humoural hypercalcemia is to use chemotherapy protocols. The support for calcium excesso is indicated since it causes unwelcoming physiologically altereations.(AU)

Hipercalcemia es el aumento de calcio total o ionizado en la corriente sanguínea y es un marcador para algunas enfermedades como las neoplasias malignas. Cuando ocurre el aumento de calcio secundario a neoplasias, se caracteriza como un síndrome paraneoplásica. Entre las neoplasias malignas que causan la hipercalcemia, el linfoma aparece en un gran porcentaje de lós hallazgos clínicos siendo el linfoma mediastinal lo que es más asociado con la hipercalcemia generando la hipercalcemia humoral maligna. EI linfoma mediastinal está asociado a la producción de células T por envolver el timo y alcanza los ganglios linfáticos mediastínicos. A través de la producción de células neoplásicas ocurre el aumento de calcio en el organismo que es resultado de la unión de proteína relacionada al paratormonio (PTHrP) a los receptores de paratormonio (PTH) causando la reabsorción ósea y por síntesis de otras sustancias que actúan como activadores de osteoclastos. La mejor forma de combatir la hipercalcemia humoral maligna es el uso de protocolos de quimioterapia. Se indica la realización de soporte para el exceso de calcio en el organismo pues el mismo, causa alteraciones fisiológicamente indeseables.(AU)

Hipercalcemia humoral maligna secundária a linfoma mediastinal em cães / Malignant humoral hypercalcemia secondary to mediastinal lymphoma in dogs / Hipercalcemia humoral maligna secundaria a linfoma mediastinal en perros

Hipercalcemia é o aumento de cálcio total ou ionizado na corrente sanguínea e é um marcador para algumas doenças como as neoplasias malignas. Quando ocorre o aumento de cálcio secundário a neoplasias, ele se caracteriza como uma síndrome paraneoplásica. Dentre as neoplasias malignas que causam a hipercalcemia, o linfoma aparece em grande porcentagem dos achados clínicos, sendo o linfoma mediastinal o que é mais associado com a hipercalcemia gerando a hipercalcemia humoral maligna. O linfoma mediastinal é associado à produção de células T por envolver o timo e atinge os linfonodos mediastinais. Através da produção de células neoplásicas ocorre o aumento de cálcio no organismo que é resultado da ligação de proteína relacionada ao paratormônio (PTHrP) aos receptores de paratormônio (PTH) causando reabsorção óssea e por síntese de outras substâncias que agem como ativadores de osteoclastos. A melhor forma de combate a hipercalcemia humoral maligna é o uso de protocolos de quimioterapia. É indicado realização de suporte para o excesso de cálcio no organismo, pois o mesmo causa alterações fisiologicamente indesejáveis.

Hypercalcemia is the high total or ionized calcium in the circulatory system and it is a marker for some diseases such as malignant neoplasms. When neoplastic secondary high calcium occurs, it characterizes as a paraneoplastic syndrome. Among malignant neoplasms that cause hypercalcemia Iynphoma appears in a huge porcent of clinical findigns, which mediastinal Iymphoma is the most hypercalcemia associated generating the malignant humoural hypercalcemia. Mediastinallymphoma is associated with the production of T cells by envolving thymus and reaches the mediastinallymphs. Throughout the production of neoplastic cells high cálcio in the organismo occurs, which is a result of the linkage of the protein related to parathyroid hormone (PTH) with the parathyroid hormone receptor (PTH) causing bone resorption and by the synthesis of other substances that work as osteoclast activators. The best way to fight malignant humoural hypercalcemia is to use chemotherapy protocols. The support for calcium excesso is indicated since it causes unwelcoming physiologically altereations.

Hipercalcemia es el aumento de calcio total o ionizado en la corriente sanguínea y es un marcador para algunas enfermedades como las neoplasias malignas. Cuando ocurre el aumento de calcio secundario a neoplasias, se caracteriza como un síndrome paraneoplásica. Entre las neoplasias malignas que causan la hipercalcemia, el linfoma aparece en un gran porcentaje de lós hallazgos clínicos siendo el linfoma mediastinal lo que es más asociado con la hipercalcemia generando la hipercalcemia humoral maligna. EI linfoma mediastinal está asociado a la producción de células T por envolver el timo y alcanza los ganglios linfáticos mediastínicos. A través de la producción de células neoplásicas ocurre el aumento de calcio en el organismo que es resultado de la unión de proteína relacionada al paratormonio (PTHrP) a los receptores de paratormonio (PTH) causando la reabsorción ósea y por síntesis de otras sustancias que actúan como activadores de osteoclastos. La mejor forma de combatir la hipercalcemia humoral maligna es el uso de protocolos de quimioterapia. Se indica la realización de soporte para el exceso de calcio en el organismo pues el mismo, causa alteraciones fisiológicamente indeseables.

Efusão Pleural em gatos: revisão de literatura e estudo retrospectivo / Pleural Effusion in cats: literature review and retrospective study

A efusão pleural é uma das principais causas de dispnéia em gatos. Diversas etiologias podem gerar a efusão pleural como neoplasias da pleura e mediastino, neoplasias do parênquima pulmonar, peritonite infecciosa felina (PIF) e cardiomiopatias. Essas doenças alteram o equilíbrio dinâmico da produção ou absorção do fluido pleural, gerando acúmulo patológico. O presente estudo analisou os casos de felinos que apresentaram efusão pleural no Hospital Veterinário da Universidade de Brasília desde de setembro de 2000 a maio de 2009. Os prontuários de vinte e três animais foram analisados e os dados coletados. Dentre as etiologias que ocasionam efusão pleural, o linfoma foi o mais comum, diagnosticado em 34,78% dos casos, seguido por piotórax (21,74%), neoplasias do parênquima pulmonar (17,39%), PIF(8,70%), cardiomiopatia (4,35%), quilotórax idiopático (4,35%) e em dois casos (8,70%) o diagnóstico permaneceu inconclusivo. Esse trabalho teve como objetivo analisar as causas de efusão pleural mais comum de dispnéia, sendo o linfoma, a causa de base mais comumente encontrada(AU)

Pleural effusion is one of the main causes of dyspnea in cats. Many diseases can result in pleural effusion such as pleural /mediastinal masses, pulmonary neoplasia, feline infectious peritonitis (FIP); and cardiomyopathy. These diseases affect physiological mechanisms of fluid formation or absorption, resulting in pathologic accumulation. The present study describes cases of cats with pleural effusion in a Veterinary Hospital. The medical records of twenty three patients were reviewed. Among the disorders that result in accumulation of pleural fluid, lymphoma was the most common, diagnosed in 34,78% of cases , followed by pyothorax (21,74%), pulmonary neoplasia (17,39%), FIP (8,70%), cardiomyopathy (4,76%), idiopathic chylothorax (4,35%) and in two cases (8,70%) the diagnosis was inconclusive. This study aimed to analyze the causes of pleural effusion occurred more common in the Veterinary Hospital. Thus, the occurrence of pleural effusion proved to be a common cause of dyspnea, and lymphoma, the underlying cause of most commonly found(AU)

Efusão Pleural em gatos: revisão de literatura e estudo retrospectivo / Pleural Effusion in cats: literature review and retrospective study

A efusão pleural é uma das principais causas de dispnéia em gatos. Diversas etiologias podem gerar a efusão pleural como neoplasias da pleura e mediastino, neoplasias do parênquima pulmonar, peritonite infecciosa felina (PIF) e cardiomiopatias. Essas doenças alteram o equilíbrio dinâmico da produção ou absorção do fluido pleural, gerando acúmulo patológico. O presente estudo analisou os casos de felinos que apresentaram efusão pleural no Hospital Veterinário da Universidade de Brasília desde de setembro de 2000 a maio de 2009. Os prontuários de vinte e três animais foram analisados e os dados coletados. Dentre as etiologias que ocasionam efusão pleural, o linfoma foi o mais comum, diagnosticado em 34,78% dos casos, seguido por piotórax (21,74%), neoplasias do parênquima pulmonar (17,39%), PIF(8,70%), cardiomiopatia (4,35%), quilotórax idiopático (4,35%) e em dois casos (8,70%) o diagnóstico permaneceu inconclusivo. Esse trabalho teve como objetivo analisar as causas de efusão pleural mais comum de dispnéia, sendo o linfoma, a causa de base mais comumente encontrada

Pleural effusion is one of the main causes of dyspnea in cats. Many diseases can result in pleural effusion such as pleural /mediastinal masses, pulmonary neoplasia, feline infectious peritonitis (FIP); and cardiomyopathy. These diseases affect physiological mechanisms of fluid formation or absorption, resulting in pathologic accumulation. The present study describes cases of cats with pleural effusion in a Veterinary Hospital. The medical records of twenty three patients were reviewed. Among the disorders that result in accumulation of pleural fluid, lymphoma was the most common, diagnosed in 34,78% of cases , followed by pyothorax (21,74%), pulmonary neoplasia (17,39%), FIP (8,70%), cardiomyopathy (4,76%), idiopathic chylothorax (4,35%) and in two cases (8,70%) the diagnosis was inconclusive. This study aimed to analyze the causes of pleural effusion occurred more common in the Veterinary Hospital. Thus, the occurrence of pleural effusion proved to be a common cause of dyspnea, and lymphoma, the underlying cause of most commonly found

ptos / Mediastinal limphoma in cats

O linfoma é definido como tumor maligno linfóide que se origina de organismos sólidos. Gatos com linfoma mediastinal são tipicamente jovens e soropositivos para FeLV e apresentam como sinais clínicos tosse, dispnéia, regurgitação e engasgos. O diagnóstico presuntivo é realizado pelo estudo radiográfico e ultra-sonográfico da cavidade torácica, sendo confirmado pela análise do fluido obtido ou pela histopatologia da massa mediastinal. Os protocolos quimioterápicos têm tido grande sucesso no tratamento de gatos com linfoma e a taxa de remissão é de aproximadamente 60 a 75% com intervalo de remissão de 251 dias, dependendo da forma anatômica e a situação da positividade para o vírus da leucemia felina (FeLV) e o vírus da imunodeficiência felina (FIV) o indicador mais significativo para um prognóstico positivo é a resposta inicial à quimioterapia. Em geral, gatos que sobrevivem ao período de indução e alcançam remissão completa têm melhor resultado a longo prazo(AU)

Lymphoma is defined as a lymphoid malignancy that originates from solid orgns. Cats with mediastinal lymphoma usually are typically young and FeLV-positive, and present for evaluation of dyspnea, coughing, or regurgitation. Thoracic radiographs may demonstrate an anterior mediastinal mass; however, a confirmatory Cytologic or hystologic diagnosis should be obtained. Chemotherapy is considered to be the most effective treatment for lymphoma in cats. Remission rates in cats with lymphoma are approximately 60 a 75% and median remission intervals of up 251 days, depending on anatomic type and FeLV status. The most significant prognostic indicator for positive outcome is initial response to chemotherapy. In general, cats that survive the initial induction period and achieve remission generally have a better long-term outcome(AU)