除骶骨之外,巨细胞瘤很少累及骨盆,尤其是发生在坐骨者,尚不足全部巨细胞瘤0.5%。作者报告了2例坐骨巨细胞瘤,均为60岁男性,骨盆平片分别显示左、右坐骨各有一边界不清的溶骨性膨胀性病变,均未见骨化、钙化及骨膜反应。第1例CT表现为左坐骨膨胀性破坏,突向髓臼,盆腔内可见大的软组织肿块,静脉尿路造影显示肿瘤在盆腔内扩展并压迫膀胱向右移位;动脉造影可见一由 In addition to the sacrum, giant cell tumors rarely affect the pelvis, especially in the ischial bone, and yet less than 0.5% of all giant cell tumors. The authors reported two giant cell tumors of the ischial bone, all of which were 60-year-old males. The pelvic plain films showed an undifferentiated osteolytic expansion lesion in each of the left and right ischial bones. No ossification, calcification, or periosteal reaction was found. In the first case, the CT showed a dilated destruction of the left ischium, a sudden protrusion of the pulp, and a large soft tissue mass in the pelvic cavity. Intravenous urography showed that the tumor expanded in the pelvic cavity and forced the bladder to shift to the right;