Pleural fluid ‘cell block’ analysis in malignant pleural effusion: sensitive, superior over fluid cytology and suitable for immunohistochemistry analysis (IHC), will decrease need for thoracoscopy guided procedures

Abstract

Abstract Prospective study conducted in Pulmonary Medicine, MIMSR Latur during Jan 2014 to june 2016, enrolled 200 cases of unexplained, exudative pleural effusion with ADA ≤30 IU/ltr and pleural fluid cytology is either positive for malignant cell with or without cell type differentiation, or cytology suspicious for malignant cell. All cases were subjected to cell block preparation. Statistical analysis was done by using chi-test. Observation and analysis In study of 200 cases, mean age of group was 68±9.5 years and adenocarcinoma was predominant malignancy in 72% cases, mesothelioma in 10% cases, squamous cell carcinoma in 7% cases & 9% cases were having primary tumor outside the thoracic cavity. In study cases pleural fluid cytology was positive in 42% cases (84/200) and pleural fluid cell block was positive in 96% cases (192/200) in detecting malignant pleural effusion (p 0.06). IHC was done in all pleural fluid cell block preparation for calretinin, cytokeratin, TTF-1 and EGFR. Conclusion: Pleural fluid cell block is sensitive, superior, cost effective and specific diagnostic method over conventional pleural fluid cytology. 9Cell block9 specimens are enough for primary diagnosis and IHC analysis necessary for cell typing. It will decrease need for more invasive and costlier diagnostic methods like thoracoscopy and image guided pleural biopsies. We recommend cell block for every exudative pleural fluid samples with ADA