A Comparative Analysis of Various Cytopreparatory Techniques in Evaluation of Serous Effusion Fluids.

Background: Cytological evaluation of serous fluids is a widely used diagnostic tool, especially when other methods are not feasible. Differentiating benign from malignant effusions is essential for guiding prognosis and treatment. However, distinguishing reactive mesothelial cells from malignant cells remains a key challenge, particularly with conventional smear (CS) techniques. Objectives: To compare the technical and cytomorphological features of serous effusion fluids using CS, cytocentrifuge smear, liquid-based cytology (LBC), and cell block (CB) preparations, and to assess the diagnostic yield of each method in detecting malignant effusions. Materials and Methods: A total of 410 serous fluid samples over a period of 2 years were processed using CS, cytocentrifuge, EziPREPTM LBC, and CB methods. Cytological features and diagnostic utility for malignancy were compared. Statistical analysis was performed using the Wilcoxon rank-sum and Friedman's ANOVA tests. Results: Samples comprised 277 pleural, 129 peritoneal, and four pericardial effusions. LBC provided statistically significant clearer back ground, while CS and CB provided significantly better staining quality and sharper morphological features. CB and LBC provided significantly high cellularity. Minimal overlapping of cells was significantly seen in cytocentrifuge and LBC smears. Additional yield for malignancy was 4% more by use of the CB method. Conclusion: Each cytological method has distinct advantages. LBC offers clearer backgrounds; CSs and CBs provide better morphology. CB and LBC show higher cellularity, with CB detecting 4% more malignancies. Combining methods may enhance the diagnostic accuracy.