SPINAL MALIGNANT NERVE-SHEATH TUMOR OR CELLULAR SCHWANNOMA - A STRIKING DIFFERENCE IN PROGNOSIS

Cellular schwannoma, a recently delineated entity, has a histological appearance mimicking that of malignant neoplasms. The aim of this stud y was to determine the outcome for patients treated for a spinal cellu lar schwannoma or malignant nerve-sheath tumor. A histological re-exam ination was conducted of 283 spinal tumors, considered to originate fr om a nerve root, that were treated in the Department of Neurosurgery b etween 1953 and 1985. After re-examination, 50 of these were determine d to be other tumors or non-neoplastic lesions. The review yielded eig ht cellular schwannomas and six malignant nerve-sheath tumors out of 2 33 of nerve-sheath origin. Immunohistochemical staining with a commerc ially available polyclonal antibody against S-100 protein was positive in all cases of cellular schwannoma, but negative for the malignant t umors. Clinical outcome was favorable for patients with cellular schwa nnomas, but uniformly poor for those with the malignant tumors.