Giant cell tumors of bone.

Giant cell tumor is a lesion that usually presents with a radiographically characteristic appearance in a predictable location and patient population. It has a few rare presentations such as pulmonary metastases and multifocal lesions. Prognosis of ultimate tumor behavior is dependent on surgical staging (which requires careful radiographic analysis to detect cortical breakthrough and joint involvement) and type of treatment. The recurrence rate is relatively high with simple curettage but decreases with adjuvant treatment at the tumor site. Optimal therapy for the more aggressive lesions is wide resection, but compromise is frequently required when such a resection would sacrifice joint function because of the subarticular location of the giant cell tumor. Radiation therapy is reserved for surgically inaccessible or otherwise inoperable lesions because of a relatively poor radiosensitivity and concerns about induction of high grade sarcomas. Radiographic follow-up evaluation for recurrence is recommended for approximately 5 years but may be difficult to interpret in individual patients because of an overlap in the appearance of healing and recurrence.