Abstract: Objective:To study the values of exfoliated cell smear, DNA ploidy analysis, cell block and their combined detection in the diagnosis of malignant pleural effusion, and to provide the evidence for the diagnosis and treatment of malignant pleural effusion. Methods:A total of 300 cases of pleural effusion specimens were analyzed by DNA ploidy analysis to judge the benign and malignant pleural effusion;the centrifuged cell pellet was used for smear, the cell block was made, and the source of malignant pleural effusion was judged by immunohistochemistry method. The sensitivities and specificities of three methods and their combined detection in the diagnosis of malignant pleural effusion were compared. Results:The sensitivities of exfoliated cell smears, DNA ploidy analysis and cell block in the diagnosis of malignant pleural effusion were 83.13%, 84.44%, and 79.52%, respectively; the specificities were 82.95%, 86.64%, and 83.87%, respectively; the sensitivity of parallel test in the diagnosis of malignant pleural effusion was 98.79%; the specificity of serial test in the diagnosis of malignant pleural effusion was 99.54%. Conclusion:The combined detection of three methods can significantly improve the clinical diagnotic effect of malignant pleural effusion compared with single detection of three methods.

Key words: DNA ploidy analysis, exfoliated cell smear, pleural effusion, cell block