Liquid-based cytology (LBC) has emerged as an alternative to conventional cytopreparatory methods. In particular, LBC has been extensively implemented in the cervical screening program, but it has found broader acceptance also in non-gynecologic cytologic preparations.
LBC uses a specially devised instrument which allows a monolayer of cells to be obtained from a liquid sample. Most studies have shown liquid based cytology system to perform as well as better than conventional preparations in non gynaecological cytology; plus, the residual cells within the vial can be used for DNA analysis or immunohistochemistry and other special studies.
The method is being used also in respiratory cytology such as in bronchial washings, sputum samples and bronchial brushings. The method allows optimal preservation of cells and additional special techniques such as immunocytochemistry, in situ hybridisation and cytometry can be applied on the same sample. However, because of its costs and less standardised criteria in mucus-rich samples, it is only used in seleceted areas of respiratory cytology.