Quality assessment and improvement of "Unsatisfactory" liquid-based cervicovaginal papanicolaou smears

The quality of cervicovaginal smears determines the success of cytology in screening programs for cervical cancer. Bethesda 2014 revisited the adequacy criteria for atrophic smears and redefined the squamous cell count in the "unsatisfactory" category. In this study, we evaluated the smear quality of Thinprep liquid-based cervicovaginal Papanicolaou cytology slides (TPS) that were previously deemed unsatisfactory, to determine reasons for such categorization. In addition, we attempted to establish the impact of the new adequacy criteria on the rate and management of unsatisfactory diagnosis.

About 234 unsatisfactory TPS were examined. The reasons for unsatisfactory were noted. The number of squamous cells was recounted, as per the new Bethesda criteria, in borderline adequacy cases that showed an atrophic pattern.

The leading cause for unsatisfactory TPS was lubricating gel, followed by blood, as observed in older and younger age groups, respectively (Figure 1). Eleven borderline cases were reclassified as "satisfactory" using the new Bethesda cell count, with 27% above 60 years of age. About 82% of these borderline cases were negative for intraepithelial lesion or malignancy on repeat testing.

There was no difference of management or change in rate of unsatisfactory when patients above 60 were reclassified into the satisfactory category using the new Bethesda count. However, a larger study is needed to evaluate whether the new recommendation for minimum cellularity can be implemented in patients above a certain age cut-off. The study highlights the need for improvement in collection practices and education of practitioners.