Giant-Cell Tumor of Bone

THE PRESENCE of multinucleated giant cells in a variety of bone lesions has led to inclusion of certain neoplastic, inflammatory, developmental, and metabolic disorders of bone under the diagnosis of giant-cell tumor or giant-cell tumor variant. In 1940, Jaffe, Lichtenstein, and Portis (1) offered a specific definition of giant-cell tumor which has gained wide, though not universal, acceptance. They considered it a distinctive neoplasm apparently arising in the nonosteoblastic connective tissue, composed of a vascularized network of spindle-shaped or ovoid stromal cells interspersed with multinuclear giant cells (which they regarded as syncytial stromal cells). In subsequent publications Jaffe and Lichtenstein (2–6) identified as distinct clinical and pathologic entities many of the lesions formerly classed as giant-cell tumor variants. Accurate identification of lesions in this category is of considerable practical importance. Most of the socalled giant-cell tumor variants are fundamentally benign lesions offering an excellent prognosis, while the true giantcell tumor is a distinctly more formidable neoplasm. Lichtenstein (7) has stated that approximately half of the proved giant-cell tumors will respond favorably to proper management, approximately a third will prove more aggressive and will recur after treatment, and the remainder ultimately will be frankly malignant. Changing concepts of the pathology of bone tumors have prompted Dahlin and associates to undertake a comprehensive review of the bone lesions encountered at the Mayo Clinic. Tissues obtained at surgical operation have been subjected to detailed gross and microscopic study, and the lesions have been reclassified in accordance with current concepts. Approximately 5 per cent of the lesions in which material was available for their review were giant-cell tumors. One practical result of a critical review in the light of changing concepts can be shown by the experience of the Mayo Clinic. In 1932, Kirklin and Moore (8) reported on the roentgenographic appearance of 86 pathologically confirmed giantcell tumors seen over a twenty-year period. On review, however, only 42 lesions encountered during that period met the revised criteria for the pathologic diagnosis of giant-cell tumor. Some of the lesions originally diagnosed as giant-cell tumor have now been reclassified pathologically as aneurysmal bone cyst, benign chondroblastoma, fibroma, benign giant-cell reparative granuloma, unicameral bone cyst, osteogenic sarcoma, fibrosarcoma, and fibrous dysplasia. The Cases Studied Williams, Dahlin, and Ghormley (9) have recently reported on the clinical and pathologic features of the giant-cell tumors observed at the Mayo Clinic. Their report was based on 101 cases seen from 1905 through December 1953. Since that report 1 of the lesions included in the series has been reclassified as an aneurysmal bone cyst and 4 new cases have been added.