The spectrum of neurological manifestations in myeloma.

Thirty-two patients with myelomatosis (3 with a solitary plasmocytoma and 29 with multiple myeloma) and neurological complications, from a group of 110 unselected patients with myelomatous disease were recorded. Spinal cord compression was the most frequent complication seen in 12 cases. In 9 subjects, it was the presenting symptom, and in 11 cases was caused by extradural plasmocytoma of the thoracic spine. Early decompressive laminectomy was curative in 3 cases, but in the rest, delay in diagnosis resulted in only partial recovery even with radiotherapy. Of the 6 patients with nerve root involvement, radiotherapy led to full recovery in 2 of 3 cases, and laminectomy resulted in complete improvement in 2 other cases. Peripheral polyneuropathy was seen in 8 cases, 2 related to systemic amyloidosis and 6 unassociated with amyloidosis. Both forms of neuropathy shared a slow progression, independent of the course of the myeloma. Acute encephalopathy, found in 6 cases, was due to hypercalcemia and/or serum hyperviscosity, and led to a significant shortening of mean survival. One patient had third cranial nerve palsy due to the overlying lesion of the skull base, and another suffered acute bacterial meningitis.