title: High diagnostic accuracy of cytologic smears of central nervous system tumors. A 15-year experience based on 4,172 patients.
abstract: OBJECTIVE
  To investigate the diagnostic accuracy and current role of intraoperative cytologic smears of central nervous system tumors.
  
  
  METHODS
  Retrospective analysis of 4,172 patients operated on during 1985-1999, with 3,541 intraoperative smears performed during open procedures and 631 during stereotactic biopsies.
  
  
  RESULTS
  Complete correlation with the final diagnosis was achieved in a mean of 89.8% (range, 83-93.7% per year). Diagnostic accuracy increased to 95% on average (range, 91.5-96.7% per year) when cases of partial correlation, mainly due to grading deviations, were included. The most accurate intraoperative diagnoses were obtained in cases of meningioma (97.9%), metastasis (96.3%) and glioblastoma (95.7%). A significant reduction in diagnostic accuracy was observed in cases of oligodendroglioma (80.9%) and ependymoma (77.7%). Besides diagnosis and grading, smear cytology provided resection guidance in cases of well-delineated tumors.
  
  
  CONCLUSIONS
  Intraoperative smears in neurosurgery are easy to obtain and inexpensive and have high diagnostic accuracy. In addition to stereotactic biopsy procedures, intraoperative smears permit reliable intraoperative guidance during lesion targeting and resection.
authors.affiliation: Cytologic Laboratory, Neurosurgical Clinic, Vienna University Medical School, Vienna, Austria. karl.roessler@univie.ac.at
authors.forename: Karl
authors.initials: K
authors.lastname: Roessler
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dietrich
authors.forename: Klaus
authors.initials: K
authors.lastname: Kitz
mesh_terms: D001706:Biopsy; D016543:Central Nervous System Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D003584:Cytological Techniques; D006801:Humans; D007432:Intraoperative Period; D012189:Retrospective Studies; D013238:Stereotaxic Techniques