Diagnostic utility of the cell block method versus the conventional smear study in pleural fluid cytology

Abstract

Background:The cytological examinations of serous effusions have been well-accepted, and a positive diagnosis is often considered as a definitive diagnosis. It helps in staging, prognosis and management of the patients in malignancies and also gives information about various inflammatory and non-inflammatory lesions. Diagnostic problems arise in everyday practice to differentiate reactive atypical mesothelial cells and malignant cells by the routine conventional smear (CS) method.Aims:To compare the morphological features of the CS method with those of the cell block (CB) method and also to assess the utility and sensitivity of the CB method in the cytodiagnosis of pleural effusions.Materials and Methods:The study was conducted in the cytology section of the Department of Pathology. Sixty pleural fluid samples were subjected to diagnostic evaluation for over a period of 20 months. Along with the conventional smears, cell blocks were prepared by using 10% alcohol–formalin as a fixative agent. Statistical analysis with the ‘z test’ was performed to identify the cellularity, using the CS and CB methods. Mc. Naemer's χ2test was used to identify the additional yield for malignancy by the CB method.Results:Cellularity and additional yield for malignancy was 15% more by the CB method.Conclusions:The CB method provides high cellularity, better architectural patterns, morphological features and an additional yield of malignant cells, and thereby, increases the sensitivity of the cytodiagnosis when compared with the CS method.

The cell block method increases the diagnostic yield in exudative pleural effusions accompanying lung cancer

“…Since some researchers used agar, plasma/ thromboplastin to bind the sedimented cells, another limitation was the risk of losing material during preparation (6,21,22). In this study, we used alcohol-formalin as a fi xative in order to get a better cellularity in CB sections.…”

“…Cell blocks provide better milieu for morphologic interpretation, with less background staining (23). Apart from increased cellularity, better morphological details such as cell balls, papillae, three-dimensional clusters, better nuclear and cytoplasmic preservation, intact cell membrane and crisp chromatin details (6). Th ey give the possibility of unlimited storage and molecular testing similar to histological samples (6)(7)(8).…”

“…Apart from increased cellularity, better morphological details such as cell balls, papillae, three-dimensional clusters, better nuclear and cytoplasmic preservation, intact cell membrane and crisp chromatin details (6). Th ey give the possibility of unlimited storage and molecular testing similar to histological samples (6)(7)(8). Immunohistochemical studies (MOC-31, D2-40, calretinin) performed on cell blocks were found to be useful in the diff erentiation between adenocarcinomas and reactive mesothelial cells (10).…”

“…Th e accurate identifi cation of cells as either malignant or reactive mesothelial cells is a challenge in conventional smear cytologies (CSS) (6). Th e cell block (CB) method is one of the oldest methods for evaluation of body cavity fl uids.…”

Role of Cell Block in Diagnostics-A New Paradigm in Cancer Diagnosis

“…The purpose of this study was to access the utility of cell blocks in increasing the cyto diagnosis of fine needle aspirates and fluids and to apply IHC markers and evaluate whether the cell block material fixed in 10% formalin is suitable for immunohistochemistry. In a similar study done by Shivakumarswamy UI et al [10]. CB method provides high cellularity, better architectural patterns, morphological features and an additional yield of malignant cells, and thereby, increases the sensitivity of the cytodiagnosis when compared with the CS method [7].…”