Squash Smear Cytology, CNS Lesions – Strengths and Limitations

摘要

Introduction: Cytodiagnosis of CNS Space Occupying Lesions (SOLs) by squash smear preparation is a rapid, inexpensive and fairly accurate diagnostic tool. Most of the studies till date have proved its utility in intraoperative consultation.Aim: This study was undertaken to evaluate accuracy of squash smear cytology and to highlight as well as analyze the diagnostic pitfalls.Materials and Methods: This study was conducted in department of pathology, Shri Guru Ram Rai Institute of Medical and Health Sciences. Intraoperative squash smears of two hundred and twenty two cases of CNS SOLs were studied. Cytological diagnoses were correlated with histopathological evaluation which was taken as gold standard. Discordant smears were reviewed and causes were analyzed.Results: An accuracy of 83.78% was achieved by squash smear cytology. The discrepancies due to interpretational errors were seen in 61.1% cases and sampling errors accounted for 38.9% cases. Cyto-histological discordance was noted more in oligodendrogliomas and grading of gliomas.Conclusion: Squash smear cytology is a fairly reliable diagnostic tool in intraoperative neuropathological consultation. Thorough sampling of tissue submitted, clinicoradiological correlation while reporting and awareness about the diagnostic pitfalls help in achieving reasonable accuracy.