Value and accuracy of cytology in addition to histology in the diagnosis of lung cancer at flexible bronchoscopy.

There is still disagreement as to the value and reliability of wash and brush cytology, in comparison with histology, for the diagnosis of malignancy at flexible bronchoscopy. The present study compares the yield and concordance of findings from the two modalities for visible tumours at flexible bronchoscopy. A single-centre study of 514 consecutive flexible bronchoscopy procedures, in which a lesion suspicious of cancer was seen and bronchial wash cytology, brush cytology and forceps biopsy samples were taken. All equivocal or suspicious results were taken as negative. An overall yield of 89.3% was achieved using a combination of all three tests. This was greater for endobronchial than submucosal (95% vs. 86%) tumours. Cytology alone diagnosed 17.7% of cases. Use of all three modalities allowed tumours to be differentiated between small and non-small cell types in all but 5/459 positive cases (98.9%). There were only 3/313 cases in which there was a difference in cell type (small cell vs. non-small cell) between the two modalities. We conclude that wash and brush cytology are valuable tools, in addition to forceps biopsy, at flexible bronchoscopy. All three tests should be performed routinely in cases of suspected malignancy.