Aims:(1) Compare the results of cell block examination and cell smear cytology in diagnosing malignant pleural effusion at the Pathology Department of Ha Dong General Hospital from 2021 to 2024. (2) Identify factors associated with cytological diagnosis using the cell block technique for pleural effusion. Materials and Methods: A cross-sectional descriptive study was conducted on 176 pleural effusion samples at the Pathology Department of Ha Dong General Hospital from October 2021 to May 2024. Results The cell block technique detected malignancy in 22.1% of samples and suspected malignancy in 5.7%, whereas the cell smear technique identified malignancy in 7.4% and suspected malignancy in 2.3%. The cell block method detected more malignant and suspicious cases than the cell smear method (p<0.05). The concordance rate between the two techniques was 79.6%. The malignancy rate was higher in males than in females (p<0.05) and was significantly higher in cases with fluid volume >500mL (p<0.05). Conclusion: The cell block technique identified more malignant and suspicious cases than the cell smear technique in diagnosing malignant pleural effusion. A significant association was found between gender, fluid volume, and cytological diagnosis using the cell block technique.

Aims:(1) Compare the results of cell block examination and cell smear cytology in diagnosing malignant pleural effusion at the Pathology Department of Ha Dong General Hospital from 2021 to 2024. (2) Identify factors associated with cytological diagnosis using the cell block technique for pleural effusion. Materials and Methods: A cross-sectional descriptive study was conducted on 176 pleural effusion samples at the Pathology Department of Ha Dong General Hospital from October 2021 to May 2024. Results The cell block technique detected malignancy in 22.1% of samples and suspected malignancy in 5.7%, whereas the cell smear technique identified malignancy in 7.4% and suspected malignancy in 2.3%. The cell block method detected more malignant and suspicious cases than the cell smear method (p<0.05). The concordance rate between the two techniques was 79.6%. The malignancy rate was higher in males than in females (p<0.05) and was significantly higher in cases with fluid volume >500mL (p<0.05). Conclusion: The cell block technique identified more malignant and suspicious cases than the cell smear technique in diagnosing malignant pleural effusion. A significant association was found between gender, fluid volume, and cytological diagnosis using the cell block technique.