ABORDAGEM INTRA E EXTRAORAL PARA EXÉRESE DE OSTEOSSARCOMA MAXILOFACIAL CANINO: RELATO DE CASO

Abstract

Osteosarcoma is a common mesenchymal neoplasm in dogs and humans. It can be classified as appendicular, axial or extraskeletal, depending on the type of bone or tissue involved. It predominates in the appendicular bones such as the radius, humerus and femur, and can metastasize in the thorax. The axial subtype includes multilobar and mandibular osteochondrosarcoma. Common in large, female and elderly dogs, representing 2 to 5% of malignant neoplasms. Maxillofacial osteosarcoma has slower progression and less metastatic tendency. The diagnosis is made by clinical examination, imaging and histopathological examinations, with immunohistochemistry being indicated to assess the prognosis. This article aimed to report a case of a 10-year-old Blue Heeler dog, complaining of sneezing with bloody discharge after regression of edema in the rostral maxilla. Tomography showed aggressive bone destruction in the maxilla, extending to the nasal cavity. Biopsy confirmed oral osteosarcoma. Chest X-rays did not reveal metastases. The patient was referred for left hemimaxillectomy with lateral rhinotomy to remove the neoplasm and the affected bone part, followed by adjuvant chemotherapy with carboplatin and cyclophosphamide. Removal of the mandibular lymph node and absence of neoplastic cells confirm the slow metastasis of maxillofacial osteosarcoma. The combination of radical surgery, chemotherapy, and consideration of prognostic markers can improve treatment outcome.