50-year-old male suffering from hip pain for the past several months. The X-ray shows osteolysis in the trochanteric area with patchy calcification; mild fibrillation of bone and clusters of erosion of the inner cortical area. Resection.
- Hyaline (occasionally myxoid) cartilage matrix in the form of nodes and lobes. Possible focal mineralisation.
- Mild to moderate cell and nuclear polymorphism, some cells with a double nucleus.
- Mild enchondral ossification: the neoplastic cartilage substance is spreading along the pre-exisitng bone structure which it can destroy. The infiltration of cartilage matrixinto the canalicular system causes an erosion of the compacta.