This study was designed to review the clinical experience of cementation in the treatment of giant cell tumor of bone and to clarify its biologic basis. Eleven patients treated by this technique had results rated excellent. No recurrences of the tumor were found. Serious complications, including infection, late fracture, or secondary osteoarthrosis, did not occur. The possibility of immediate fixation and stabilization of large defects is the most valuable point of this method. Local recurrence seems to be easily detectable by magnetic resonance imaging. A cell line of mononuclear cells from giant cell tumor of bone was examined for its response to hyperthermic exposure. Hyperthermic treatment was carried out at temperature of 60 Β° for 10 min and in other conditions. The numbers of cells surviving after heat treatment were counted, and flow cytometry was used to analyze the positive rate of surface antigens of the cells and the pattern of DNA distribution at the different temperatures. The heat treatment caused a fair number of the cells to fall into S-phase, and the tetraploid value was very low. The higher the temperature and the longer the time, the fewer cells survived and the less the expression of the monocytic phenotype. No cells survived after heating at 60 Β° for 10 min. Cementation seemed to have a hyperthermic effect to the cells of giant cell tumor of bone.