Metastatic Osteosarcoma of the Distal Femur in a Korean Water Deer (Hydropotes inermis argyropus).

A free-living female Korean water deer (Hydropotes inermis argyropus) was found with swelling in the left femur. Radiographic and histopathologic examination confirmed distal femoral osteosarcoma with metastases to the inguinal lymph node and the lungs; there are no previous reports of osteosarcoma in water deer.