Giant-cell tumor of the sacrum. Clinical and radiologic features in 13 patients.

Thirteen patients were found to have giant-cell tumors during a study of 91 primary tumors of the sacrum. This tumor was second only to the chordoma in incidence. Giant-cell tumor is by far the commonest benign lesion of the sarcrum, yet it has a bad prognosis. Recurrences occurred in seven patients and five died of disease or a complication. All were histologically benign when first seen, but one developed a malignant giant-cell tumor and died within two years, and one developed a radiation-induced sarcoma 10 years following treatment. Computed tomography in two recent patients proved to be the most valuable single examination. Arteriography is helpful in showing the degree of vascularity of the tumor and the exact position of the large vessels, particularly important when surgical resection is planned.