1. Use of microfiltration technique to improve diagnostic accuracy of pleural effusion cytology

2. The cytological examination of the pleural effusion has a major role in the management of patients with suspicion of or confirmed lung cancer. Smear quality from pleural effusions is dependent on smear preparation techniques.

3. The purpose of our study was to present a new method for enhacing pleural effusions diagnostic accuracy by improving cellular yield using microfiltration.

4. Pleural effusion from 10 selected patients  lung cancer suspicion  confirmed lung cancer Cytopreparation  Microfiltration  Smears

5. Fixation and Stains  Hemacolor (air-dried smears)  Cytocolor (alcohol-fixed smears) Pleural Efussion Microfiltation CytocolorHemacolor

6. Image acquisition Microphotos (4x objective) Morphometry  cellularity  presence or absence of cellular aggregates

9. We found that microfiltration of pleural effusion produces better cellularity, in average 400 cells/field. This, compared to other methods was significantly higher (p<0,05).

10. Direct CentrifugatedMicrofiltrated

11. Cellular conglomerates were present in nearly all cases, also a better preservation of cellular morphology was observed.

12. Additionally we found that smears stained with Cytocolor showed visibly better quality as compared to Hemacolor stained slides.

13. Microfiltration of pleural effusions is a new method of improving smear cellularity. Its routine use is expected to enhance the diagnostic value of effusion cytology in the management of lung cancer patients.

14. This method also concentrates cells in smaller area, therefore requires a shorter smear analysis time compared with other techniques. The presence of cell aggregates further underlines its potential in increasing pleural effusion cytology specificity and sensitivity.