Chondrosarcoma in the humerus of a goat.

The clinical, radiographical and histo-pathological findings of a chondrosarcoma in the humerus of a goat are discussed. An 11-year-old female Saanen goat was admitted for evaluation of chronic, progressive left forelimb lameness. Clinical examination revealed signs of pain in the shoulder region. Radiographs of the scapulohumeral joint showed a large lytic lesion of the proximal third of the humerus with cortical destruction, intralesional calcification and marked periosteal reactions. Differential diagnoses included aggressive bone lesions as seen with osteomyelitis or a primary bone tumour, such as osteosarcoma, chondrosarcoma or fibrosarcoma. The goat was euthanatized for humane reasons because of the poor prognosis. On the basis of the histopathological findings, the lesion was diagnosed as grade II chondrosarcoma. The tumour had already spread to the lungs and the left prescapular lymph node at the time of diagnosis.