Background: A new approach like squash smears and frozen section to diagnose CNS neoplasm intra-operatively can help the neuro-pathologist in an intra-operative setting to diagnose and provide sufficient preliminary information to optimize the surgical management of the patient, especially in stereotactic surgery. Majority of the CNS lesions have better preserved cytological detail in squash smear, however tissue architecture is preserved in frozen section. Hence along with squash smear, frozen section is used to emphasize its advantages for intra-operative diagnosis. Thus a study is undertaken in a tertiary care hospital as to compare the efficacy of squash cytology and frozen section with histopathology diagnosis, considering it as the gold standard.

Material & Method: All the neurosurgical specimen with suspected CNS neoplasm received in the Department of pathology of IMS & SUM Hospital for intra-operative consultation was studied prospectively for a period of 3years(august 2014-july 2017). Intra-operative squash cytology and simultaneous frozen section were done and the diagnosis were compared with the final paraffin-embedded section.

Result and Observation: A total of 18.89% of case were found discordant in squash smears and 21.12% of cases were discordant for frozen section considering the histopathology as gold standard .Technical errors like thick smearing artefact, frozen artefact, limited tissue sample, crushed specimen cautery induced &crushing artefacts contributed to misdiagnosis.

Conclusion: Though the squash smears showed a reasonably higher percentage of diagnostic accuracy over frozen section in intra-operative diagnosis of CNS neoplasm, both the procedures should be used complementarily and not as substitution.

Study type and design: Hospital based cross-sectional study & is an observational study.

Keywords: central nervous system lesions, comparative efficay, squash cytology, frozen section, histopathology.

1. Jha B , Patel V, Patel K, Agarwal A. Role of squash smear techniquein intraoperative diagnosis of CNS tumours.Int J Med Sci Public Health 2013;2:889-92.
2. Bhagya Lakshmi A, Vishnu Prasad K, Uma P, Satyanarayana Rao P, Krishnaprasad P, Hygreev Rao B,et al. Role of squash smears, imaging and histopathology in diagnosing CNS lesions – A prospective study. National Journal of Basic Medical Sciences 2012;II:213-20.
3. Govindaram PK, ArumugamN, Ramasamy C, Prakasam G.Role of squash smear in intraoperative consultation of central nervous systemtumours. J SciSoc 2017;44: 7-14.
4. Firlik KS, Martinez AJ, Lunsford LD.Use of cytological preparation for the intraoperative diagnosis of stereotactically obtained brain biopsies: a 19 year experience and survey of neuropatho-logists. Journal of neurosurgery 1999;91: 454-8.
5. Amraei R, Moradi A, Zham H, Ahadi M, Baikpour M, RakhshanA,et al. A comparision between diagnostic accuracy of frozen section and permanent section analysis in central nervous system. Asian Pac J Cancer Prev 2017;18 : 659-66.
6. Shah AB, Mazumdar GA, Chitale AR, Bhagwati SN. Squash preparation and frozen section in intraoperative diagnosis of central nervous system tumours. Actacytol 1998;42: 1149-54.
7. Krishnappa I, Myageri A, Shaitri DU, Rao R. Diagnostic dilemmas in intraoperative diagnosis of glial neoplasm.j Cancer Biol Res 2017;5:1092
8. Jaafar H, Intra-Operative Frozen Section Consultation: Concept, Applications, Limitations; Malaysian Journal of Medical Sciences 2006;13:14-2
9. Samal S, Katra R, Sharma J, Singh I, Panda D, Ralli M. Comparision between crush/squash cytology and frozen section preparation in intraoperative diagnosis of central nervous system lesions. Oncol J India 2017;1:25-30.
10. Savargaonkar P, Former MP.Utility of intraoperative consultation for the diagnosis of central nervous system lesions. Ann of Clin Lab Sci 2001;31 :133-9.
11. Patil SS, Kudrimoti JK, Agarwal RD, Jadhav MV, Chuge A. Utility of squash smear cytology in intraoperative diagnosis of central nervous system tumours. J cytol 2016; 33:205-9
12. Verma SK, Kumar R, Srivani J, Arnold J. Diagnostic accuracy of squash preparations in central nervous system tumors. Iran j pathol 2013;8:227-34.
13. Chapter in a book: Jerome Taxy, Aliya Husain, Anthony Montag; Biopsy Interpretation: The Frozen Section.1st edition, 2009; 329-32.
14. Iqbal M, Azra S, Wani MA, Kirmani A, Ramzan A .Cytopathology of CNS.. Part I- Utility of crush smear cytology in intraoperative diagnosis of CNS lesions. Acta Cytologica 2006; 50:608-16.
15. Mitra S, Kumar M, Sharma V, Mukhopadhyay D.squash preparation: A reliable diagnostic tool in the intraoperative diagnosis of central nervous system tumors.jcytol 2010;27:81-85

Dr Debahuti Mohapatra

Professor and Head, Department of Pathology, IMS and SUM Hospital, Bhubaneswar751003, Odisha, India

Email: This email address is being protected from spambots. You need JavaScript enabled to view it., Cell: 09439831760