Diagnostic Utility and Accuracy of Scrape Cytology in Evaluation of Neoplastic Lesions

Background: Frozen section, intraoperative fine needle aspiration cytology (FNAC) and imprint cytology have been used traditionally by the surgical pathology laboratories for rapid intraoperative diagnosis of tumors. Scrape cytology is a modification of imprint cytology that involves lightly scraping or brushing cells from freshly cut surface of the surgically removed tumor specimens. The present study was carried out to evaluate the utility of scrape cytology in diagnostic evaluation of tumors.

Material and methods: A prospective study was carried out at a tertiary care teaching hospital in Central India. A total of 50 consecutively received specimens in the Department of Pathology and Laboratory Medicine with clinical or radiological suspicion of neoplasia were included in the study. Scrape smears were prepared from freshly cut surface of tumor specimens received unfixed or in 10% formalin.

Results: Overall, the scrape cytology diagnosis was concordant with final histopathological diagnosis in 48 out of 50 cases with a diagnostic accuracy of 96%. The sensitivity was 90.9% (CI-58.72% to 99.77%) and specificity was 97.4%(CI-86.52% to 99.94%). Positive predictive value and negative predictive value were 90.91% and 97.44%, respectively.

Conclusion: Scrape cytology is a cost-effective and reasonably accurate cytodiagnostic technique for rapid tumor diagnosis. Scrape cytology can be a useful supplementary tool to frozen section, and may be applied for rapid diagnosis where frozen section technique is not available. The material and knowledge obtained from scrape cytology of routinely received histopathological specimens can be utilized as a teaching material and may help unveil diagnostic cytopathological features of infrequent cytologically encountered lesions.