Les tumeurs à cellules géantes de l'os

Giant-cell tumors (GCT) are rarely observed in bone, occurring in 4 % to 9.5 % of all bones tumor. The diagnosis is often strongly suggested by the pathological radiologic features. A meta-epiphyseal localization is common with extension to sub chondral bone. Computed tomography and magnetic resonance imaging are helpful in staging lesions and determining soft-tissue extension. An association with other bone lesions, such as aneurismal bone cysts, is reported in 14 % of GCT. However, biopsy must be directed to solid regions, which harbor diagnostic tissue. Multiple GCT are rare. Malignant GCT account for 5 to 10 % of all GCT, usually secondary to previous radiation of a benign GCT. Treatment requires surgical resection and recurrence can be seen in 2 to 25 % of cases. We present a descriptive study of 13 cases of bone GCT, illustrating the clinical and radiographic features of classic and atypical bone GCT.