Liquid-based cytology using CytoRich Red/Tripath is diagnostically equivalent to conventional smears for bronchial washings and brushings and reduces the cost.

A split sample study was performed on 109 bronchial brushings and washings and evaluated from conventional slides (CS) and CytoRich Red/Tripath preparations (CRR/Tripath). Unassessable bronchial washings were significantly more frequent in CS (5 vs. 0), but as all brushings were assessable with both methods, no overall diagnostic advantage was found. CS and CRR/Tripath gave discordant diagnoses in one case with a final benign diagnosis and in six cases with final malignant diagnoses. In the benign case, atypia was assessed in CS. In the malignant cases, suspected malignancy was found in one CRR/Tripath and one CS, atypia vs. benign assessment was also balanced, with three atypias in CRR/Tripath and two in CS. The better preserved cells in CRR/Tripath facilitated correct diagnosis in some cases, but might also lead to false positive diagnoses. In small cell carcinomas diagnostic hints such as smearing and moulding were less pronounced in CRR/Tripath but this did not affect the diagnostic accuracy. Overall, the diagnostic performance with CRR/Tripath was at least as good as with conventional slides, although statistically no difference could be seen. The number of slides and screening time, and thereby cost was significantly reduced with CRR/Tripath, thus the liquid-based method is preferred for bronchial washings and brushings.