Immunocytochemical evaluation of central nervous system tumors obtained by the Cavitron ultrasonic surgical aspirator.

The Cavitron ultrasonic surgical aspirator (CUSA) is a dissecting system that allows quick and effective removal of CNS tumors without traction or excessive manipulation of normal tissue. In this article, the immunoperoxidase staining patterns of cytology specimens obtained with the CUSA are compared with those from their corresponding resected surgical specimens employing a battery of monoclonal and polyclonal antibodies. Eleven cases of meningioma, three cases of glioblastoma multiforme, one astrocytoma, and two schwannomas were evaluated. In both CUSA cytologic biopsies and surgical biopsies, all the meningiomas showed strong staining for vimentin and epithelial membrane antigen, while two showed focal staining for cytokeratins. The glioblastoma multiforme and astrocytoma cases showed positivity for vimentin, S-100 protein, and glial fibrillary acidic protein, while the schwannomas stained positively for vimentin and S-100 protein. With only rare exceptions, the immunocytochemistry of the CUSA and surgical specimens correlated well in all of these cases in terms of strength of reaction and localization. There were no false-positive staining reactions in the CUSA material. This study suggests that reliable morphologic and immunoperoxidase studies can be performed on cytologic material obtained by the CUSA, which could aid in making an accurate and specific diagnosis of a variety of CNS tumors.