Simultaneous osteosarcoma in two limbs of a Maltese dog

Osteosarcoma (OSA) is rarely diagnosed in small breed dogs and it is usually restricted to a single bone, despite its aggressive biological behavior. This paper aims to report a rare case of OSA in an eight-year-old female spayed Maltese dog with simultaneous presentation in thoracic and pelvic limbs, associated with lung and kidney micrometastasis. Physical exam revealed an increase volume in the distal region of the left femur and in the proximal region of the left humerus with intense pain sensibility at palpation. Pelvic limb´s radiographs revealed an extensive area of bone lysis in the distal femur, lamellated periosteal reaction and formation of the Codman triangle, while in the thoracic limb, it was evident a cortical fracture of the proximal humerus and mixed periosteal reaction, suggestive of neoplastic or infectious disease. Cytological analysis showed the presence of a large number of malignant star-shaped cells, with prominent anisocytosis and anisokaryosis, moderate to prominent cellular and nuclear pleomorphism, rare mitotic figures, besides abundant extracellular matrix compatible with osteoid, suggestive of osteosarcoma. Histopathological findings were compatible with OSA. The dog died of a cardiorespiratory arrest and necropsy revealed a grade II osteoblastic osteosarcoma in the humerus and femur, along with renal metastasis and neoplastic emboli in the kidney and lungs.

Simultaneous osteosarcoma in two limbs of a Maltese dog

Osteosarcoma (OSA) is rarely diagnosed in small breed dogs and it is usually restricted to a single bone, despite its aggressive biological behavior. This paper aims to report a rare case of OSA in an eight-year-old female spayed Maltese dog with simultaneous presentation in thoracic and pelvic limbs, associated with lung and kidney micrometastasis. Physical exam revealed an increase volume in the distal region of the left femur and in the proximal region of the left humerus with intense pain sensibility at palpation. Pelvic limb´s radiographs revealed an extensive area of bone lysis in the distal femur, lamellated periosteal reaction and formation of the Codman triangle, while in the thoracic limb, it was evident a cortical fracture of the proximal humerus and mixed periosteal reaction, suggestive of neoplastic or infectious disease. Cytological analysis showed the presence of a large number of malignant star-shaped cells, with prominent anisocytosis and anisokaryosis, moderate to prominent cellular and nuclear pleomorphism, rare mitotic figures, besides abundant extracellular matrix compatible with osteoid, suggestive of osteosarcoma. Histopathological findings were compatible with OSA. The dog died of a cardiorespiratory arrest and necropsy revealed a grade II osteoblastic osteosarcoma in the humerus and femur, along with renal metastasis and neoplastic emboli in the kidney and lungs.(AU)

Lesions of hypertrophic osteopathy in the forelimbs of a dog associated with pulmonary metastasis from a periostealosteosarcoma

Hypertrophic osteopathy is commonly associated with primary lung neoplasms. It may also be secondary to intrathoracic lesions such as pulmonary metastasis, granulomatous pleurisy and chronic pneumonia, among others. It is characterized by progressive proliferation of sub periosteal bone tissue in limb bones. Clinically, patient usually exhibits lameness. It is a rare disease most frequently observed in dogs among domestic animals. A case of a dog with pulmonary hypertrophic osteopathy associated with pulmonary metastases coming from an appendicular periosteal osteosarcoma is reported.

Lesions of hypertrophic osteopathy in the forelimbs of a dog associated with pulmonary metastasis from a periostealosteosarcoma

Hypertrophic osteopathy is commonly associated with primary lung neoplasms. It may also be secondary to intrathoracic lesions such as pulmonary metastasis, granulomatous pleurisy and chronic pneumonia, among others. It is characterized by progressive proliferation of sub periosteal bone tissue in limb bones. Clinically, patient usually exhibits lameness. It is a rare disease most frequently observed in dogs among domestic animals. A case of a dog with pulmonary hypertrophic osteopathy associated with pulmonary metastases coming from an appendicular periosteal osteosarcoma is reported.(AU)

Total hemipelvectomy in a cat with osteoblastic osteosarcoma / Hemipelvectomia total em um gato com osteossarcoma osteoblástico

Background: Osteosarcoma (OSA) is a malignant neoplasm of mesenchymal tissue that exhibits various histological features and a differentiated biological clinical behavior.The combination of clinical, radiological, and histopathological features is important for diagnosis. Surgical treatment of neoplasms with pelvic involvement is a challenge.Primary bone tumors are rare in cats and are mostly reported in older animals. The objective of this paper was to report the case of a feline subjected to total hemipelvectomy as primary treatment of pelvic OSA; the surgical technique and histological analysis of the tumor are described.No signs of recurrence were seen during seven months of follow-up. Case: A 4-year-old female mixed breed cat weighing 3 kg was presented with a one year history of increased volume on the hip joint region. Palpation of the increased volume on the hip showed a firm, adhered, and painful mass. Radiographic examination of the pelvis in the dorso ventral projection exhibited a severe osteoblastic bone reaction on the proximal femur, as well as marked periosteal reaction of the hip joint with involvement of the acetabulum. A ventral approach total hemipelvectomy technique was adopted for excision of the tumor. The animal was placed on a lateral position and a circumferential skin incision was performed on the ipsilateral limb of the affected hemipelvis, on the [...](AU)

Total hemipelvectomy in a cat with osteoblastic osteosarcoma / Hemipelvectomia total em um gato com osteossarcoma osteoblástico

Background: Osteosarcoma (OSA) is a malignant neoplasm of mesenchymal tissue that exhibits various histological features and a differentiated biological clinical behavior.The combination of clinical, radiological, and histopathological features is important for diagnosis. Surgical treatment of neoplasms with pelvic involvement is a challenge.Primary bone tumors are rare in cats and are mostly reported in older animals. The objective of this paper was to report the case of a feline subjected to total hemipelvectomy as primary treatment of pelvic OSA; the surgical technique and histological analysis of the tumor are described.No signs of recurrence were seen during seven months of follow-up. Case: A 4-year-old female mixed breed cat weighing 3 kg was presented with a one year history of increased volume on the hip joint region. Palpation of the increased volume on the hip showed a firm, adhered, and painful mass. Radiographic examination of the pelvis in the dorso ventral projection exhibited a severe osteoblastic bone reaction on the proximal femur, as well as marked periosteal reaction of the hip joint with involvement of the acetabulum. A ventral approach total hemipelvectomy technique was adopted for excision of the tumor. The animal was placed on a lateral position and a circumferential skin incision was performed on the ipsilateral limb of the affected hemipelvis, on the [...]

Osteopatia hipertrófica secundária a osteossarcomacondroblástico extraesquelético em um cão / Hypertrophic osteopathy secondary to extraskeletal chondroblastic osteosarcoma in a dog

Background: hypertrophic osteopathy is a periosteum disturb characterized by diffuse new bone formation which leads tosignificant thickening and deformity of members. Secondary in nature, it usually follows large pulmonary lesions such asabscesses and neoplasms. Extraskeletal osteosarcomas are rare and extremely malignant mesenchymal neoplasms. Theycomprise approximately 1% of all domestic animals’ osteosarcomas and develop in the absence of a primary bone lesion.The aim of this paper was to describe a case of hypertrophic osteopathy, involving joints and upper limbs bones includingilium, secondary to a mediastinal chondroblastic osteosarcoma with pulmonary metastasis.Case: A 10-year-old spayed female mixed breed dog, weighing 9 kg, was presented with painful limbs, lameness, hind limbsswelling and a four-month history of weight loss. Radiographic examination revealed bilateral and asymmetric periostealreactions on diaphyseal and/or epiphyseal areas of all proximal phalanges; metacarpal, metatarsal, carpal and tarsal bones;radius; ulna; tibia; fibula; humerus; femur and right ilium. An increased soft tissue radiopacity was noted on the lateral sideof the right knee joint. Thoracic radiographies and ultrasonography suggested the presence of a 5-cm neoplasm or abscessin the left caudal lung lobe. At necropsy, the lobe showed a firm and solid, oval white mass measuring 5.2 x 2.9 cm. Anothermass was found in the caudal mediastinum, near the diaphragm, with same color and more irregular aspect, measuring 3.3cm of diameter. Intense periosteal new-bone formation was seen in the entire length of the four limbs bones, characterizedby thickening of the bone surface and formation of irregular trabeculae perpendicular to the cortex. Significant swelling andthickening of the joint capsule was noted in the right knee. There was no microbial growth on aerobic or anaerobic culturesfrom the masses samples sent to culture. [...]

Osteopatia hipertrófica secundária a osteossarcomacondroblástico extraesquelético em um cão / Hypertrophic osteopathy secondary to extraskeletal chondroblastic osteosarcoma in a dog

Background: hypertrophic osteopathy is a periosteum disturb characterized by diffuse new bone formation which leads tosignificant thickening and deformity of members. Secondary in nature, it usually follows large pulmonary lesions such asabscesses and neoplasms. Extraskeletal osteosarcomas are rare and extremely malignant mesenchymal neoplasms. Theycomprise approximately 1% of all domestic animals osteosarcomas and develop in the absence of a primary bone lesion.The aim of this paper was to describe a case of hypertrophic osteopathy, involving joints and upper limbs bones includingilium, secondary to a mediastinal chondroblastic osteosarcoma with pulmonary metastasis.Case: A 10-year-old spayed female mixed breed dog, weighing 9 kg, was presented with painful limbs, lameness, hind limbsswelling and a four-month history of weight loss. Radiographic examination revealed bilateral and asymmetric periostealreactions on diaphyseal and/or epiphyseal areas of all proximal phalanges; metacarpal, metatarsal, carpal and tarsal bones;radius; ulna; tibia; fibula; humerus; femur and right ilium. An increased soft tissue radiopacity was noted on the lateral sideof the right knee joint. Thoracic radiographies and ultrasonography suggested the presence of a 5-cm neoplasm or abscessin the left caudal lung lobe. At necropsy, the lobe showed a firm and solid, oval white mass measuring 5.2 x 2.9 cm. Anothermass was found in the caudal mediastinum, near the diaphragm, with same color and more irregular aspect, measuring 3.3cm of diameter. Intense periosteal new-bone formation was seen in the entire length of the four limbs bones, characterizedby thickening of the bone surface and formation of irregular trabeculae perpendicular to the cortex. Significant swelling andthickening of the joint capsule was noted in the right knee. There was no microbial growth on aerobic or anaerobic culturesfrom the masses samples sent to culture. [...](AU)