Giant cell tumor of bone. Prognosis and treatment of pulmonary metastases.

Giant cell tumor of bone is a challenging clinicopathologic entity. Despite its benign designation, it has the capacity to recur locally and develop rare pulmonary metastases. Between 1945 and 1991, 104 patients with histologically benign giant cell tumors of bone, 5 of which metastasized to the lung, were treated at the authors' institution. In these cases, histologic materials from the lung were identical to those found in the primary bone lesion. The primary bone lesions were treated with local curettage (3), wide resection (1), and wide resection with prosthesis placement (1). The patients were observed for a mean of 12.6 years (range, 5-38 years). Four of the 5 patients experienced local recurrences (average time interval, 34 months), with 3 patients experiencing 2 or more recurrences. The average time to lung metastasis was 23 months; 1 patient presented initially with pulmonary findings. Four patients underwent surgical resection of pulmonary metastases. All 4 patients are alive with no disease progression, despite incomplete pulmonary resections in 2 patients. Locally aggressive disease and multiple recurrences appear to be risk factors for pulmonary metastases in benign giant cell tumor of bone. Pulmonary metastases occurred within the first few years after discovery of primary bone tumors. Radiographs and computed tomographs of the chest are recommended to rule out this complication in patients with local recurrences. Resection of pulmonary metastasis is recommended. Long term survival is not incompatible with persistent pulmonary lesions.