Intraoperative Frozen Section of Central Nervous System Lesions: A Single-Center Study on Diagnostic Accuracy from Western India
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Keywords
CNS, Frozen section, accuracy
Abstract
Background: Accurate intraoperative diagnosis of central nervous system (CNS) lesions is essential for surgical management and optimal patient outcomes. While formalin-fixed, paraffin-embedded (FFPE) histopathology remains the gold standard, frozen section (FS) offers real-time guidance to neurosurgeons.
Methodology: This retrospective study evaluated 31 consecutive cases of CNS lesions subjected to FS consultation and subsequent paraffin section (PS) diagnosis between January 2017 and December 2024. Lesions were categorized using the latest 2021 WHO CNS classification of tumours. FS and PS results were assessed for concordance (complete, partial, or none), and diagnostic performance metrics, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy were calculated.
Results: Among 31 cases (mean age 45 years), 28 were neoplastic and 3 non-neoplastic. Complete FS-PS concordance occurred in 58% of cases, partial in 35.5%, and none in 6.5%. FS demonstrated a sensitivity of 100%, specificity of 50%, PPV of 96.7%, NPV of 100%, and overall accuracy of 96.8%. Concordance rates and accuracy aligned with published literature. Discrepancies predominantly resulted from sampling and technical errors or tumour histological complexity.
Conclusion: Intraoperative FS provides high diagnostic accuracy and sensitivity, highlighting its significance and utility as an effective and beneficial tool for neurosurgeons in CNS lesion management. Though technical limitations and tissue artefacts remain significant challenges, optimal outcomes can be obtained by integration of cytology smears, imaging findings, intraoperative navigation, and multidisciplinary collaboration between neurosurgeons, radiologists, and pathologists. Further studies with larger cohorts are warranted to validate findings.
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