Principles in the Examination and Management of Bone Neoplasms; Normal Elements and the Cytologic Features of Reactive Changes in the Bone

摘要

Primary bone tumors are relatively uncommon. Osteosar-coma is the most frequent primary bone sarcoma, followed by chondrosarcoma, Ewing sarcoma, and chordoma. Among benign bone neoplasms, the most common are os-teochondroma, giant cell tumor, chondroma, osteoid oste-oma, and metaphyseal fibrous defect.Regarding the distribution of malignant and benign bone tumors respectively by histologic type and by age of patient, it is obvious that the majority of benign bone tumors, osteo-sarcoma, and Ewing sarcoma, arise in children and young adults, while chondrosarcoma and chordoma occur most frequently in the elderly. Generally, skeletal sarcomas have a bimodal age distribution, with the highest risk of development during the second decade of life and the second peak of incidence after the age of 60 years.