Intraoperative squash cytology of CNS and spinal cord lesions with histologic correlation

  • Sanjeev Kishore Shri Guru Ram Rai Institute of Medical and Health Science
  • Aparna Bhardwaj Shri Guru Ram Rai Institute of Medical and Health Science
  • Anuradha Kusum Himalyan Institute of Medical science, Jollygrant, Dehradun
  • Brijesh Thakur Shri Guru Ram Rai Institute of Medical and Health Science
  • Sanjay Kaushik Shri Guru Ram Rai Institute of Medical and Health Science
  • Neetika Sharma Shri Guru Ram Rai Institute of Medical and Health Science
Keywords: Central Nervous System, Histopathology, Squash cytology.


Background:  Squash Cytology is now a well established and universally accepted technique in diagnosing a wide range of Central Nervous System (CNS) lesions and is presently being employed for both therapeutic and prognostic reasons.  This study was conducted with an aim to correlate squash smears with histopathology and to compare statistical data employing sensitivity, specificity and diagnostic accuracy of squash cytology. Methods: The present study was a retrospective study comprising 369 lesions of central nervous system and spinal cord that were retrieved from archives. All the cases for which Intraoperative squash cytology and subsequent histopathology was available were included in the study. Cytology smears were stained with May- Grunwald- Geimsa (MGG), Hematoxylin & Eosin (H&E) and Pap stain. Histopathology smears were made from formalin fixed tissue sent separately and stained with H&E.Results: Of 369 cases, 86.4% were neoplastic and 13.6% nonneoplastic on histopathology. Amongst neoplasms, Astrocytic tumors constituted 24.7% of cases followed by Meningiomas comprising 17.8%. Amongst the benign lesions Tuberculoma was seen most frequently (3.25%). Overall diagnosticAccuracy of squash was 95.25%. On statistical analysis Sensitivity, Specificity, Positive Predictive value (PPV) and Negative Predictive Value (NPV) of squash cytology were 94.3%, 95.6%, 95.3% and 95.1% respectively. On applying student T test, for statistical correlation between squash cytology and histopathology p value was 0.363347 (p>0.05) hence errors in diagnosis by squash were insignificant. Conclusion: Intraoperative squash cytology is fairly accurate, reliable and cost effective method for rapid diagnosis of CNS lesions.

Author Biographies

Sanjeev Kishore, Shri Guru Ram Rai Institute of Medical and Health Science
Department of Pathology, Proffessor & Head
Aparna Bhardwaj, Shri Guru Ram Rai Institute of Medical and Health Science
Department of Pathology, Assosciate Proffessor
Anuradha Kusum, Himalyan Institute of Medical science, Jollygrant, Dehradun
Department of Pathology, Proffessor
Brijesh Thakur, Shri Guru Ram Rai Institute of Medical and Health Science
Department of Pathology, Assistant Proffessor
Sanjay Kaushik, Shri Guru Ram Rai Institute of Medical and Health Science
Department of Pathology, Assistant Proffessor
Neetika Sharma, Shri Guru Ram Rai Institute of Medical and Health Science
Department of Pathology, Assistant Proffessor


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Original Article

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