Evaluation of the CytoRich technique for cervical smears

The aim of the study was to assess the ability of the CytoRich System to prepare optimal gynaecological smears for diagnosis. The diagnostic results obtained from evaluating 1,325 matched slide-pairs, prepared using conventional methods and thin-layer technology, were compared. Cytological material for study was obtained using the combined spatula-cytobrush sampling technique. An assessment of the pitfalls associated with the interpretation of these smears was also undertaken. Diagnostic agreement was achieved in 1,272 of the 1,325 matched slide-pairs (96.0%), and these included 1,172 negative, 50 atypical, 24 low-grade squamous intraepithelial lesion (LSIL), 24 high-grade SIL (HSIL), and two malignancies. A total of 1,309 cases showed the same diagnosis within one diagnostic grade for an agreement of 98.8%. Evaluation of the 53 discordant diagnoses revealed that the conventional smear identified a significantly greater number of abnormal smears than the CytoRich technique (P < .001). It is suspected that the use of the combined spatula-cytobrush sampling technique did not provide adequate residual specimen for CytoRich after conventional smear preparation. This limitation is evidenced by the fact that the CytoRich preparations showed a lower yield of endocervical cells (P < .001) and infectious organisms (P < .001) than was demonstrated on conventional smears. Despite a number of diagnostic pitfalls associated with the interpretation of thin-layer smears, these preparations were easier and faster to screen and showed well-preserved and evenly distributed cells. Thin-layer smears were also characterised by a marked reduction in thick cell groups, air drying artifact, and obscuring inflammation and blood. The results confirm the limitation of the combined spatula-cytobrush technique in these types of comparative studies.