Cell Block: A Tool to Improve Cytopathologic Diagnostic Value of Fine Needle Aspiration Material

Abstract

Background: The various advantages of Fine-needle aspiration (FNA) biopsy/ cytology can be limited due to inadequacy of the specimen and expertise required for diagnosis. Cell blocks (CBs), though routinely used in cytology of body fluids, can also be used in FNA material with considerable increase in diagnostic accuracy. Aims & objectives: To compared FNA & CB as diagnostic tool and to evaluate whether cell block adds to the diagnostic accuracy of FNA.
 Methods: This is a two years prospective study carried out in the pathology department of a tertiary heath care hospital and medical college of South India which included the cases undergoing the FNAC, and followed by the biopsy. CB was prepared using Tissue coagulum clot (TCC) method. The smears and tissue sections were assessed for cellularity and adequacy for diagnosis. CBs were grouped into four diagnostic categories. FNA & CB were compared with histopathology (HPE) diagnosis to calculate Sensitivity, Specificity and Diagnostic Accuracy.
 Result: A total of 195 cases were included. Cellularity and adequacy for diagnosis were higher in CB. They were diagnostically better (superior) in 13.84% (27) cases. The sensitivity (95.77%) and diagnostic accuracy (94.87%) of CB was found to be considerably higher than FNA (78.84% and 78.46% respectively).
 Conclusion: In cases of suspicious/ intermediate diagnosis or diagnosis discordant with clinical ones, by FNA; should be followed with the CB to improve the diagnostic yield & to facilitate accurate diagnoses. TCC method is a simple CB method which has higher diagnostic accuracy than FNA.