Cauda equina compression associated with breast cancer. A case study in differential diagnosis.

The determination of the etiology of spinal cord compression in cancer patients is essential for appropriate therapy. Patients with metastatic disease are not immune to the development of superimposed nonmalignant disease. Although metastatic epidural compression may occur in up to 9% of breast cancer patients, care must be taken to rule out other nonmetastatic lesions causing compression. The association of concurrent breast carcinoma and a spinal neurilemoma simulating a metastatic lesion seems not to have been previously reported. A neurilemoma was observed in a 50-year-old woman. A neurilemoma suspected to be a metastatic lesion may produce the clinical features of pain, neurologic deficit, and weakness. Differentiation will be aided by roentgenograms, radionuclide bone scans, computed tomography, and possible magnetic resonance imaging. Radiologic differentiation hinges on the recognition and the slow-growing nature and noninvasive boundaries of the nonmalignant lesion. Ultimate verification is by biopsy. Treatment should consist of neurectomy, if severely symptomatic, and stabilization as indicated.