RESUMO
Cellblock technique (CB) is one of the oldest techniques of preparing materials for microscopic examination by paraffin embedding of sediments of fluids. CB enables retrieval of small tissue fragments from fluids, improving the cellular yield and diagnostic accuracy. The main advantage of CB is the potential to make many sections for special stains and ancillary techniques like IHC. Objective: To compare the efficacy of cellblock vs. centrifuged smear examination in effusions and fluids from cystic lesions. Methods: A total of 220 samples which included effusions (pleural, peritoneal, pericardial and synovial fluids), CSF, BAL fluids and fluids from cystic lesions were studied and categorized by both routine centrifuged smear and cellblock preparation by fixed sediment method. For CB categorization, volume of fluid and presence of pellet were given due importance. Results: Majority of the samples were pleural fluids (34.1%) followed by peritoneal fluids (29.1%) and fluids from cystic lesions (22.1%). Male to female ratio was 1.2:1 with peak age between 40- 70 years. On CS 86.8% were benign, 1.8% were suspicious for malignancy, 8.2% were positive for malignancy and 3.3% were inadequate for opinion. CBs were non-contributory in 65.9%, in 27.2%, CBs confirmed CS diagnosis and in 4.5% they established a specific diagnosis. (Sensitivity 63%, specificity 71.7%, PPV 80%, NPV 94.6%)(Kappa value = 0.175, p value=0.001). Volume of the fluid did not matter in malignant effusions and material on CB was seen in majority of these fluids with the presence of pellet formation.Among the non-neoplastic fluids material on CB was seen with volume >10ml with a good pellet formation. Conclusion: CBs were complementary to CS in the overall categorization of benign and malignant groups. However, they appeared to be more useful in diagnosis of malignancy by better-preserved architectural patterns and provided material for ancillary techniques like histochemistry and IHC.In CB, presence of pellet after centrifugation may be an indicator for the availability of material.