World Health Organization publishes classification of bone tumors

The classification of bone tumors is based on the cell of origin, especially the type of differentiation shown by the tumor cells and the type of stroma produced. The classification of bone tumors published by the World Health Organization (WHO) in 1993 is as follows:

1. Benign

Benign bone tumors include: ① Osteogenic tumors: osteoma, osteoid osteoma, osteoblastoma, etc.; ② Chondrogenic tumors: osteochondroma (most common) chondroma, enchondroma, etc.; ③ Vascular tumors: hemangioma, glomus tumor, etc. ④ Tumor-like lesions: solitary bone cyst, myositis ossificans, etc. ⑤ Others, such as osteoclastoma, bone marrow tumor, lipoma, schwannoma, etc.

2. Intermediacy

Intermediate tumors include: ① invasive osteoblastoma ② hemangioendothelioma ③ hemangiopericytoma ④ ligamentous fibroma ⑤ aneurysmal bone cyst ⑥ eosinophilic granuloma ⑦ hyperparathyroidism brown tumor.

3. Malignant

Malignant tumors include: ① Osteosarcoma: medullary osteosarcoma, well-differentiated intrabone osteosarcoma, periosteal osteosarcoma, etc.; ② Chondrosarcoma: periosteal chondrosarcoma, mesenchymal chondrosarcoma, clear cell chondrosarcoma, etc.; ③ Vascular tumors: angiosarcoma, malignant hemangiopericytoma; ④ Connective tissue tumors: fibrosarcoma, liposarcoma, malignant mesenchymal tumor, leiomyosarcoma, chordoma, etc. ⑤ Bone marrow tumors: Ewing sarcoma, primitive neuroectodermal tumor of bone, malignant lymphoma of bone, myeloma.