Primary localized histiocytic sarcoma of the lumbar vertebrae in a four-toed hedgehog (Atelerix albiventris).

We describe a case of primary localized histiocytic sarcoma of the lumbar vertebrae in a four-toed hedgehog. The case showed aggressive osteolysis of lumbar vertebrae on radiography, and a soft-tissue mass effacing this region was noted, suggesting a neoplastic lesion. No metastatic lesions were apparent. Antemortem diagnosis was challenging, and necropsy was performed. Histopathological and immunohistochemical findings were consistent with localized histiocytic sarcoma. This report provides documentation of the clinical and pathologic features of an unusual form of histiocytic sarcoma localizing to lumbar vertebrae in a four-toed hedgehog.