Malignant tumors of the pelvic girdle mimicking the herniated disk syndrome.

Sarcomas of the pelvic girdle may produce signs and symptoms indistinguishable from those of herniated lumbar disks. Five patients are described in which the diagnosis was more difficult than in patients with intraspinal or vertebral neoplasms because they demonstrated isolated nerve root abnormalities, a positive history of trauma, an absence of radiographic abnormalities, and a lack of symptoms usually associated with malignancy. Four of the 5 patients underwent laminectomy for suspected herniated disks. In such cases a correct diagnosis often can not be made at the outset but the necessity for frequently repeated clinical and radiographic examinations cannot be overemphasized.