Document Type : Original Research


Dept. of Pathology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Gorimedu, Puducherry, India


Background & Objectives: The accurate assessment of the diseased tissue is fundamental to the diagnosis and management of disorders of the central nervous system (CNS). The ‛squash’ or ‛crush’ technique has been universally employed in the intraoperative diagnosis of CNS tumors. The aim of our study was to evaluate the accuracy of squash preparation in diagnosing CNS tumors by comparing with histopathology.
Methods: This was a descriptive study which included 63 patients with CNS tumors from whom most of the samples were collected by craniotomy. Squash smears were made and stained with H&E, Papanicolaou & May-Grunwald Giemsa stains. Paraffin sections were made from formalin fixed tissue sent separately.
Results: Of 63 cases, squash cytology diagnosis correlated with histopathology in 56 cases with a diagnostic accuracy of 88.9%. A 100% accuracy was seen in pilocytic astrocytoma, anaplastic astrocytoma, glioblastoma, ependymoma, anaplastic ependymoma, choroid plexus papilloma, schwannoma, hemangioblastoma, craniopharyngioma, prolactinoma and metastases. Of the 7 cases which did not correlate with histopathology, one was a sampling error, 4 were diagnostic errors and 2 were instances of grading discrepancy.
Conclusion: Squash preparations are a highly effective tool in the rapid intraoperative diagnosis of CNS tumors. It is a simple, reliable, cost effective procedure which in most cases can help the operating surgeon to come to a correct decision regarding the further management of the patients.


  1. Silverberg SG, DeLellis RA, Frable WJ, LiVolsi VA, Wick MR. Silverberg’s principles and practice of surgical pathology and cytopathology. 4th ed. Philadelphia:Churchill Livingstone; 2006.
  2. Fletcher CDM. Diagnostic histopathology of tumors. 3rd ed. Philadelphia:Churchill Livingstone;2007.
  3. Eisenhardt L, Cushing H. Diagnosis of intracranial tumors by supravital technique. Am J Path 1930;6(5):541-52.
  4. Russell DS, Krayenbuhl H, Cairns H. Wet film technique in histological diagnosis of intracranial tumors-Rapid method. J Pathol Bacteriol 1937;45(3):501-5.
  5. Powell SZ. Intraoperative consultation, cytologic preparations, and frozen section in the central nervous system. Arch Pathol Lab Med 2005;129(12):1635-52
  6. Roessler K, Dietrich W, Kitz K. High diagnostic accuracy of cytologic smears of CNS tumors. Acta Cytol 2002;46(4):667-74.
  7. 7.Shukla K, Parikh B, Shukla J, Trivedi P, Shah B. Accuracy of cytologic diagnosis of central nervous system tumors in crush preparation. Indian J Pathol Microbiol 2006;49(4):483-6.
  8. Mouriquand C, Benabid AL, Breyton M. Stereotactic cytology of brain tumors. Review of an 8 year experience. Acta Cytol 1987;31(6):756-64.
  9. Bleggi-Torres LF, de NoronhaL, Gugelmin ES , Sebastião APM , Werner B, Maggio EM, et al. Accuracy of the smear technique in the cytological diagnosis of 650 lesions of the central nervous system. Diagnostic Cytopathol 2001;24(4):293-5.
  10. Firlik KS, Martinez AJ, Lunsford LD. Use of Cytological preparations for the intraoperative diagnosis of stereotactically obtained brain biopsies: a 19 year experience and survey of neuropathologists. J Neurosurg 1999;91(3):454-8.
  11. Cappabianca P, Spaziante R, Caputi F, Pettinato G, Del Basso De Caro M, Carrabs G, et al. Accuracy of analysis of multiple small fragments of glial tumors obtained by stereotactic biopsy. Acta Cytol 1991;35(5):505-9.
  12. Malhotra V, Puri H, Bajaj P. Comparison of smear cytology with histopathology of the CT guided stereotactic brain biopsy. Indian J of Pathol Microbiol 2007;50(4): 862-4.
  13. Shah AB, Muzamdar GA, Chitale AR, Bhagwati NS. Squash preparation and frozen section in intraoperative diagnosis of CNS tumors. Acta Cytol 1998;42(5):1149-54.
  14. Kini JR, Jeyraj V, Jayaprakash CS, Indira S, Naik CNR. Intraoperative consultation and smear cytology in the diagnosis of brain tumours. Kathmandu Univ Med J. 2008;6(24):453-7.
  15. Folkerth RD. Smears and Frozen section in intraoperative diagnosis of CNS lesions. Neuro Surg Clin N Am 1994;5(1):1-18.
  16. Goel D, Sundaram C, Paul TR, Uppin SG, Prayaga AK, Panigrahi MK, et al. Intraoperative cytology (squash smear) in neurosurgical practice- pitfalls in diag nosis experienced bases on 3057 samples from a single institution. Cytopathology 2007;18(5): 300–8.