Chondrosarcoma in a dromedary camel (Camelus dromedarius)

Abstract

A 4-year 10-month-old, intact female dromedary camel had progressive left carpal joint swelling and lameness for 7 months. Radiographs showed multifocal lytic lesions in the carpal and proximal metacarpal bones. Surgical biopsy of the synovial capsule and carpal bones suggested neoplasia, and the camel was subsequently euthanized. At necropsy, a white to pale pink, firm, multilobulated, soft tissue mass was located on the palmar aspect of the left carpal joint. Two smaller masses were present on the dorsal aspect of the carpal joint. The masses infiltrated all the carpal bones and the proximal region of the metacarpal bone. The joint capsule was diffusely thickened. The articular surfaces of the carpal bones and the metacarpal bone were multifocally eroded. The lungs contained multiple, firm, raised, gray, randomly distributed nodules. The neoplastic cells stained positive for vimentin and S-100. Chondrosarcoma arising from around the carpal joint with infiltration of carpal and metacarpal bones, and pulmonary metastasis, was diagnosed based on the histopathological and immunohistochemical evaluation.