Use of Intraoperative Squash Smear in Diagnosis of Central Nervous System Tumors with its Histopathological Correlation

Abstract

Introduction: Squash smear preparation is a simple and rapid methodology for fairly accurateintraoperative diagnosis of CNS space occupying lesions. It has emerged as an important indispensibleintraoperative diagnostic aid guiding the neurosurgeon and helping in better management of patients.The current study was undertaken to study CNS tumors by squash cytology and correlating them withhistological diagnosis.Aims: To evaluate the accuracy and utility of intraoperative squash smear cytology in the evaluationof CNS tumors.Materials and Methods: A retrospective study was conducted in the Department of Pathology in atertiary care hospital from November 2019 to November 2020. A total of 74 consecutive cases wereincluded. Squash smears were prepared from the intraoperative samples and biopsy samples wereprocessed regularly. Hematoxylin and eosin staining was done and squash smear cytology results werecorrelated with the final histopathological diagnosis.Results: Out of the 74 cases studied, histopathological diagnosis was compatible with the cytologicaldiagnosis in 56 cases, pertaining to 75.67% accuracy. Remaining 18 cases showed partial discrepancyas in tumor grading or complete discrepancy.Conclusion: This study shows a high degree of cytohistological correlation. With clinicoradiologicalcorrelation, squash smear cytology could be the preferred method for intraoperative diagnosis of CNStumors.