Fibroblastic osteosarcoma in a guinea pig (Cavia porcellus)

The article describes the case of a 3 year 6 months old Guinea Pig (Cavia porcellus) that was assisted at the Wildlife and Exotic Animal Practice of the Faculty of Veterinary Sciences, National University of Asunción. The patient presented a hard mass in the right hind limb extending from the proximal portion of the femur, projecting caudally to the proximal tuberosity of the calcaneus, with an increase in temperature, and a marked increase in sensitivity. Radiographic diagnosis refers to a mass with amorphous areas of mineral density. Fine needle aspiration puncture revealed an undifferentiated malignant proliferative process, requiring histopathological analysis to characterize the process. Disarticulation was performed and subsequent histopathologic diagnosis under hematoxylin-eosin and Masson's trichrome stain revealed fibroblastic osteosarcoma.(AU)

Osteossarcoma pélvico metastático em cão / Metastatic pelvic osteosarcoma in a dog

Background: Osteosarcomas are malignant neoplasms of bone tissue, with a high prevalence in dogs, especially in large and giant breeds. More commonly, such alterations affect the appendicular skeleton and, to a lesser extent, the axial skeleton. In order to obtain an accurate diagnosis, it is necessary to combine cytological and histopathological findings with clinical parameters, imaging exams and macroscopic findings. In the present study, we report a rare case of combined-type pelvic osteosarcoma with pulmonary metastasis in a dog. Case: A 5-year-old intact large male dog of mixed breed, was submitted to clinical care because of an increase in volume of the left perineal region. The cytological evaluation, performed without imaging exams, indicated that it was an undifferentiated sarcoma. An incisional biopsy defined the diagnosis as telangiectatic osteosarcoma, and with progressive clinical worsening, the patient died. Necroscopic examination revealed multiple nodules in the lungs and an irregular mass with a hard to friable consistency. The mass was intensely vascularised and extended craniodorsally from the left ischial tuberosity to the base of the renal fossa. Microscopically, the neoplasm was diagnosed as combined osteosarcoma, consisting of the osteoblastic, chondroblastic, and telangiectatic subtypes. Metastases with a predominance of the chondroblastic subtype were observed in the lungs. Discussion: This is the first report of combined-type canine osteosarcoma in the ischium. The case reported here is unusual, as there are few reports of canine osteosarcoma in the pelvic bones, and there is no concrete information regarding its histological appearance. Osteosarcoma is the most common bone neoplasm in dogs, representing up to 80% of the tumours found in such organs. In the present case, the dog was a large young adult with a higher probability of neoplasm development. A cytopathological examination is a diagnostic method with good sensitivity and specificity that can confirm osteosarcomas. However, in this case, the cytological diagnosis, performed without the information from the imaging exam, indicated that it was an undifferentiated sarcoma, given the impossibility of the architectural assessment of the lesion. Biopsy samples sent for histology may not be representative of the entire tumour, leading to misclassification of the histological type. Therefore, the evaluation of fragments from various sites of the lesions is recommended. Regarding the morphology of osteosarcomas, such neoplasms have the osteoblastic, chondroblastic, fibroblastic, telangiectatic, large cell, and poorly differentiated subtypes. With regard to tumours located in the axial skeleton, no studies have assessed the predominance of a particular morphological type, as well as the incidence of combined-type masses in dogs in this particular location. Such neoplasms are locally aggressive and have a high metastatic potential, with the lungs being the main location for implantation of neoplastic cells. There is no proven evidence of the correlation between morphological presentations and the presence of metastases from osteosarcomas in dogs. The histological type is not a predictive factor for the behaviour of the neoplasm. However, the anatomical location is considered as one of the factors with the greatest influence on the prognosis and metastatic potential. Rib masses are associated with a higher rate of metastases compared to others. The definitive diagnosis of osteosarcomas and its correct subclassification are of great importance in the prognosis of affected patients. These require an approach that considers the clinical findings, imaging examinations, and macroscopic and microscopic alterations.

Fibroblastic osteosarcoma in a white-eared opossum (Didelphis albiventris) / Osteossarcoma fibroblástico em gambá-de-orelha-branca (Didelphis albiventris)

Osteosarcoma is characterized by the production of osteoid or woven bone, using neoplastic osteoblasts. It is the most common primary bone neoplasm in canines and humans. This neoplasm was previously reported in all vertebrate classes, including a wide variety of mammals. However, there is no case report describing this neoplasm in Didelphis albiventris. Therefore, the objective of this manuscript is to describe the clinical-pathological aspects of fibroblastic osteosarcoma in D. albiventris. A wild adult male white-eared opossum (D. albiventris) arrived at the zoological park of the "Universidade de Caxias do Sul" with a swollen left thoracic limb. After a general clinical examination, the animal was transferred to the Veterinary Clinic of "Universidade de Caxias do Sul" for radiographic examination of the left thoracic limb and thorax. Additionally, some material was collected through fine needle aspiration (FNA) for cytologic evaluation. The radiographic findings and cytologic evaluation indicated osteosarcoma. The animal was euthanized due to severe clinical conditions and guarded prognosis. During necropsy, macroscopic analysis of the viscera was performed, fragments of various organs were collected and fixed in 10% neutral buffered formalin. All fragments were processed following routine histological techniques. The histopathological evaluation confirmed osteosarcoma, which was classified as a fibroblastic subtype. Case reports are crucial for the knowledge of incidence, prevalence, and behavior of the current mentioned disease, as well as other diseases, in species with such limited information. In order to obtain a decisive diagnosis, a few different examination methods were associated. Although the observations presented are based on a single case, this neoplasm had a similar clinical presentation to that described in other species.(AU)

O osteossarcoma é caracterizado pela produção de osteoide ou osso imaturo, por osteoblastos neoplásicos. É a neoplasia óssea primária mais comum em caninos e humanos. Essa neoplasia já foi relatada em todas as classes de vertebrados, incluindo uma grande variedade de mamíferos. Não havendo descrição dessa neoplasia até o momento em Didelphis albiventris. O objetivo deste trabalho é descrever aspectos clínico-patológicos de um caso de osteossarcoma fibroblástico em D. albiventris. Chegou para atendimento no Zoológico da Universidade de Caxias do Sul um gambá-de-orelha-branca (D. albiventris), macho, adulto, de vida livre com aumento de volume no membro torácico esquerdo. Após avaliação clínica geral, o animal foi encaminhado para a Clínica Veterinária da Universidade de Caxias do Sul para realização de radiografia do membro torácico esquerdo e de tórax, sendo também realizada coleta de material por punção aspirativa por agulha fina (PAAF) para avaliação citológica. Os achados radiográficos e da avaliação citológica foram sugestivos de osteossarcoma. Devido ao estado clínico grave e prognóstico reservado optou-se pela eutanásia. Durante a necropsia realizou-se a análise macroscópica das vísceras, foram coletados fragmentos de diversos órgãos, fixados em formalina 10%, processados pelas técnicas histológicas de rotina. Na avaliação histopatológica confirmou-se a suspeita de osteossarcoma sendo classificado no subtipo fibroblástico. A descrição de relatos é fundamental para conhecimento da incidência, prevalência e comportamento desta e de outras doenças em espécies que as informações são limitadas. A associação de diferentes métodos de exames foram necessários para a obtenção de um diagnóstico definitivo. Embora as observações apresentadas se baseiem em um caso único, esta neoplasia possuiu apresentação clínica semelhante a descrita em outras espécies.(AU)

Fibroblastic osteosarcoma in a white-eared opossum (Didelphis albiventris)

ABSTRACT: Osteosarcoma is characterized by the production of osteoid or woven bone, using neoplastic osteoblasts. It is the most common primary bone neoplasm in canines and humans. This neoplasm was previously reported in all vertebrate classes, including a wide variety of mammals. However, there is no case report describing this neoplasm in Didelphis albiventris. Therefore, the objective of this manuscript is to describe the clinical-pathological aspects of fibroblastic osteosarcoma in D. albiventris. A wild adult male white-eared opossum (D. albiventris) arrived at the zoological park of the Universidade de Caxias do Sul with a swollen left thoracic limb. After a general clinical examination, the animal was transferred to the Veterinary Clinic of Universidade de Caxias do Sul for radiographic examination of the left thoracic limb and thorax. Additionally, some material was collected through fine needle aspiration (FNA) for cytologic evaluation. The radiographic findings and cytologic evaluation indicated osteosarcoma. The animal was euthanized due to severe clinical conditions and guarded prognosis. During necropsy, macroscopic analysis of the viscera was performed, fragments of various organs were collected and fixed in 10% neutral buffered formalin. All fragments were processed following routine histological techniques. The histopathological evaluation confirmed osteosarcoma, which was classified as a fibroblastic subtype. Case reports are crucial for the knowledge of incidence, prevalence, and behavior of the current mentioned disease, as well as other diseases, in species with such limited information. In order to obtain a decisive diagnosis, a few different examination methods were associated. Although the observations presented are based on a single case, this neoplasm had a similar clinical presentation to that described in other species.

RESUMO: O osteossarcoma é caracterizado pela produção de osteoide ou osso imaturo, por osteoblastos neoplásicos. É a neoplasia óssea primária mais comum em caninos e humanos. Essa neoplasia já foi relatada em todas as classes de vertebrados, incluindo uma grande variedade de mamíferos. Não havendo descrição dessa neoplasia até o momento em Didelphis albiventris. O objetivo deste trabalho é descrever aspectos clínico-patológicos de um caso de osteossarcoma fibroblástico em D. albiventris. Chegou para atendimento no Zoológico da Universidade de Caxias do Sul um gambá-de-orelha-branca (D. albiventris), macho, adulto, de vida livre com aumento de volume no membro torácico esquerdo. Após avaliação clínica geral, o animal foi encaminhado para a Clínica Veterinária da Universidade de Caxias do Sul para realização de radiografia do membro torácico esquerdo e de tórax, sendo também realizada coleta de material por punção aspirativa por agulha fina (PAAF) para avaliação citológica. Os achados radiográficos e da avaliação citológica foram sugestivos de osteossarcoma. Devido ao estado clínico grave e prognóstico reservado optou-se pela eutanásia. Durante a necropsia realizou-se a análise macroscópica das vísceras, foram coletados fragmentos de diversos órgãos, fixados em formalina 10%, processados pelas técnicas histológicas de rotina. Na avaliação histopatológica confirmou-se a suspeita de osteossarcoma sendo classificado no subtipo fibroblástico. A descrição de relatos é fundamental para conhecimento da incidência, prevalência e comportamento desta e de outras doenças em espécies que as informações são limitadas. A associação de diferentes métodos de exames foram necessários para a obtenção de um diagnóstico definitivo. Embora as observações apresentadas se baseiem em um caso único, esta neoplasia possuiu apresentação clínica semelhante a descrita em outras espécies.

Epidemiological and pathologic aspects of extra-skeletal osteosarcoma in dogs / Aspectos epidemiológicos e patológicos do osteossarcoma extraesquelético em cães

Extra-skeletal osteosarcoma is a malignant mesenchymal neoplasm that originates from soft tissue. This tumor occurs spontaneously in dogs, but there are few cases described in the literature. The objective of this study was to describe the epidemiological and pathologic features of extra-skeletal osteosarcoma in 36 dogs. Cases diagnosed as osteosarcoma affecting dogs (n=216), during 2006 to 2016 were reviewed. Of these, 36 cases were diagnosed as extra-skeletal osteosarcoma. The mean age of affected dogs was 10.4 years, and the mean weight was 19.5kg. No breed predisposition was observed. The most frequently affected sites were the mammary glands (80.6%; 29/36), subcutaneous tissue (5.6%; 2/36), liver (5.6%; 2/36), spleen (2.8%; 1/36), omentum (2.8%; 1/36), and kidney (2.8%; 1/36). Histological examination revealed that 61.1% (22/36) of the tumors were osteoblastic, 33.3% (12/36) chondroblastic, 2.8% (1/36) fibroblastic, and 2.8% (1/36) were giant cell-rich osteosarcomas. Histological grade II and III were the most frequent. Lymph node metastases were observed in 21.4% (3/14) of the cases of mammary gland osteosarcoma. Distant metastases were observed in 23.1% (3/13) of cases by diagnostic imaging and in 71.4% (5/7) during autopsy. Metastases were observed in the lungs (57.1%; 4/7), liver (14.3%; 1/7), spleen (14.3%; 1/7), and in multiple sites (14.3%; 1/7). Pulmonary metastases were more frequently observed in cases of mammary gland osteosarcoma.

Osteossarcoma extraesquelético é uma neoplasma mesenquimal maligno que se origina de tecidos moles. O neoplasma ocorre espontaneamente em cães, mas há poucos casos descritos na literatura. Este trabalho teve como objetivo descrever os aspectos epidemiológicos e patológicos do osteossarcoma extraesquelético em 36 cães. Casos diagnosticados de osteossarcoma afetando cães (n=216), durante 2006 a 2016 foram revisados. Deste total, 36 casos tiveram diagnóstico de osteossarcoma extraesquelético. A média de idade foi de 10,4 anos, não houve predisposição racial e o peso médio foi de 19,5kg. Os locais acometidos foram glândula mamária (80,6%; 29/36), tecido subcutâneo (5,6%; 2/36), fígado (5,6%; 2/36), baço (2,8%; 1/36), omento (2,8%; 1/36) e rim (2,8%; 1/36). Na histologia, 61,1% (22/36) eram osteoblásticos, 33,3% (12/36) eram condroblásticos, 2,8% (1/36) eram fibroblásticos e 2,8% (1/36) eram ricos em células gigantes. Os graus histológicos II e III foram os mais frequentes. Metástases nodais estavam presentes em 21,4% (3/14) dos casos que ocorreram na mama. Metástases distantes foram constatadas em 23,1% (3/13) dos casos por exames de imagem e em 71,4% (5/7) dos casos pela autópsia. Os locais de metástases foram pulmões (57,1%; 4/7), fígado (14,3%; 1/7), baço (14,3%; 1/7) e em múltiplos sítios (14,3%; 1/7). Metástases pulmonares foram mais frequentes em cadelas com osteossarcoma de glândula mamária.

Epidemiological and pathologic aspects of extra-skeletal osteosarcoma in dogs / Aspectos epidemiológicos e patológicos do osteossarcoma extraesquelético em cães

Extra-skeletal osteosarcoma is a malignant mesenchymal neoplasm that originates from soft tissue. This tumor occurs spontaneously in dogs, but there are few cases described in the literature. The objective of this study was to describe the epidemiological and pathologic features of extra-skeletal osteosarcoma in 36 dogs. Cases diagnosed as osteosarcoma affecting dogs (n=216), during 2006 to 2016 were reviewed. Of these, 36 cases were diagnosed as extra-skeletal osteosarcoma. The mean age of affected dogs was 10.4 years, and the mean weight was 19.5kg. No breed predisposition was observed. The most frequently affected sites were the mammary glands (80.6%; 29/36), subcutaneous tissue (5.6%; 2/36), liver (5.6%; 2/36), spleen (2.8%; 1/36), omentum (2.8%; 1/36), and kidney (2.8%; 1/36). Histological examination revealed that 61.1% (22/36) of the tumors were osteoblastic, 33.3% (12/36) chondroblastic, 2.8% (1/36) fibroblastic, and 2.8% (1/36) were giant cell-rich osteosarcomas. Histological grade II and III were the most frequent. Lymph node metastases were observed in 21.4% (3/14) of the cases of mammary gland osteosarcoma. Distant metastases were observed in 23.1% (3/13) of cases by diagnostic imaging and in 71.4% (5/7) during autopsy. Metastases were observed in the lungs (57.1%; 4/7), liver (14.3%; 1/7), spleen (14.3%; 1/7), and in multiple sites (14.3%; 1/7). Pulmonary metastases were more frequently observed in cases of mammary gland osteosarcoma.(AU)

Osteossarcoma extraesquelético é uma neoplasma mesenquimal maligno que se origina de tecidos moles. O neoplasma ocorre espontaneamente em cães, mas há poucos casos descritos na literatura. Este trabalho teve como objetivo descrever os aspectos epidemiológicos e patológicos do osteossarcoma extraesquelético em 36 cães. Casos diagnosticados de osteossarcoma afetando cães (n=216), durante 2006 a 2016 foram revisados. Deste total, 36 casos tiveram diagnóstico de osteossarcoma extraesquelético. A média de idade foi de 10,4 anos, não houve predisposição racial e o peso médio foi de 19,5kg. Os locais acometidos foram glândula mamária (80,6%; 29/36), tecido subcutâneo (5,6%; 2/36), fígado (5,6%; 2/36), baço (2,8%; 1/36), omento (2,8%; 1/36) e rim (2,8%; 1/36). Na histologia, 61,1% (22/36) eram osteoblásticos, 33,3% (12/36) eram condroblásticos, 2,8% (1/36) eram fibroblásticos e 2,8% (1/36) eram ricos em células gigantes. Os graus histológicos II e III foram os mais frequentes. Metástases nodais estavam presentes em 21,4% (3/14) dos casos que ocorreram na mama. Metástases distantes foram constatadas em 23,1% (3/13) dos casos por exames de imagem e em 71,4% (5/7) dos casos pela autópsia. Os locais de metástases foram pulmões (57,1%; 4/7), fígado (14,3%; 1/7), baço (14,3%; 1/7) e em múltiplos sítios (14,3%; 1/7). Metástases pulmonares foram mais frequentes em cadelas com osteossarcoma de glândula mamária.(AU)

Fibroblastic osteosarcoma of scapula in a dog Scottish Terrier: case report / Osteossarcoma fibroblástico de escápula em cão Scottish Terrier: relato de caso

Osteosarcoma (OSA) is the most primary bone tumor observed in dogs. It a malignant neoplasias that affects the bone formation being with aggressive clinical-histological behavior a fast growth and high metastatic potential. Is observed in middle aged or older dogs with large or giant breed and restricts to the metaphysis of long bones of appendicular skeleton. In routine there was a Scottish Terrier dog attended, male, ten years old, that arrived intermittent claudication of the left forelimb, sensitivity to palpation and edema of firm consistency in the cervicothoracic region, with no previous historic of fractures or trauma. The association of clinical signs with the radiographic cytological and histopathological aspects resulted in the definitive diagnosis of fibroblastic OSA in scapula. The treatment was the amputation of LTM, promoting pain relief with little or none loss of quality of life.

Osteossarcoma (OSA) é o tumor ósseo primário mais observado em cães. Trata-se de uma neoplasia maligna que afeta a formação do osso, com comportamento clínico-biológico agressivo, crescimento rápido e altamente metastático. É mais observado em cães de meia idade, com porte grande ou gigante e, em geral, restringe-se à metáfise dos ossos longos do esqueleto apendicular. Foi atendido um cão Scottish Terrier macho de dez anos de idade que chegou com claudicação intermitente do membro torácico esquerdo (MTE), sensibilidade à palpação e edema de consistência firme na região cervicotorácica, sem nenhum histórico prévio de fraturas ou traumas. O diagnóstico definitivo de OSA fibroblástico escapular foi realizado com base na associação entre os achados clínicos, radiográficos, citológicos e histopatológicos. O tratamento utilizado foi a amputação do MTE, promovendo alívio da dor com pouca ou nenhuma perda da qualidade de vida.

Fibroblastic osteosarcoma of scapula in a dog Scottish Terrier: case report / Osteossarcoma fibroblástico de escápula em cão Scottish Terrier: relato de caso

Osteosarcoma (OSA) is the most primary bone tumor observed in dogs. It a malignant neoplasias that affects the bone formation being with aggressive clinical-histological behavior a fast growth and high metastatic potential. Is observed in middle aged or older dogs with large or giant breed and restricts to the metaphysis of long bones of appendicular skeleton. In routine there was a Scottish Terrier dog attended, male, ten years old, that arrived intermittent claudication of the left forelimb, sensitivity to palpation and edema of firm consistency in the cervicothoracic region, with no previous historic of fractures or trauma. The association of clinical signs with the radiographic cytological and histopathological aspects resulted in the definitive diagnosis of fibroblastic OSA in scapula. The treatment was the amputation of LTM, promoting pain relief with little or none loss of quality of life.(AU)

Osteossarcoma (OSA) é o tumor ósseo primário mais observado em cães. Trata-se de uma neoplasia maligna que afeta a formação do osso, com comportamento clínico-biológico agressivo, crescimento rápido e altamente metastático. É mais observado em cães de meia idade, com porte grande ou gigante e, em geral, restringe-se à metáfise dos ossos longos do esqueleto apendicular. Foi atendido um cão Scottish Terrier macho de dez anos de idade que chegou com claudicação intermitente do membro torácico esquerdo (MTE), sensibilidade à palpação e edema de consistência firme na região cervicotorácica, sem nenhum histórico prévio de fraturas ou traumas. O diagnóstico definitivo de OSA fibroblástico escapular foi realizado com base na associação entre os achados clínicos, radiográficos, citológicos e histopatológicos. O tratamento utilizado foi a amputação do MTE, promovendo alívio da dor com pouca ou nenhuma perda da qualidade de vida.(AU)

Cutaneous metastasis of osteosarcoma in a dog: case report / Metástase cutânea de osteossarcoma em um cão: relato de caso

This article relates a case of a three-year-old male Rottweiler dog, with diagnostic of fibroblastic osteosarcoma on left femur distal third, associated with cutaneous metastasis. It"s detached the rare occurrence of this found in dog, being an aggravating factor for the prognostic of this disease.

Relata-se neste trabalho o caso de um cão Rottweiler, macho, de três anos de idade, com diagnóstico de osteossarcoma fibroblástico em terço distal de fêmur esquerdo, associado a metástase cutânea. Ressalta-se a insólita ocorrência deste achado em cães, sendo este um fator agravante para o prognóstico desta enfermidade.