A feasibility study of the AutoPap system location-guided screening

Abstract

Objective: To study the feasibility of AutoPap System location-guided screening and to evaluate the accuracy of the AutoPap System in selecting locations of potentially abnormal cellular material, the accuracy of triaging slides using the selected locations and the improvement in laboratory accuracy and workload reduction resulting from a combination of location-guided rescreening and AutoPap System primary screening.

Study design: For the study, 683 conventionally prepared cervical cytologic smears (263 WNL, 184 atypical squamous cells of undetermined significance/atypical glandular cells of undetermined significance, 173 low grade squamous intraepithelial lesions, 55 high grade squamous intraepithelial lesions and 8 cancer slides) were acquired from nine laboratories. The study slides were independently screened to establish study reference diagnoses. The slides were processed on the AutoPap System and screened by cytotechnologists who were guided by the field of view (FOV) locations provided by the AutoPap System. The location-guided information was used either for initial manual screening (location-guided screening or after initial manual screening of the entire slide (location-guided rescreening). The results were compared to the study reference diagnoses. Sensitivity and workload reduction figures were estimated for different slide populations.

Results: The accuracy of location-guided slide triage was high and did not vary significantly over different slide populations. Also, for > 80% of the abnormal slides, the AutoPap System-selected FOV slide locations did contain the most diagnostic cells, which were used to assign an accurate diagnosis to the slide. By combining location-guided rescreening with AutoPap primary screening, the estimated overall location-guided screening false negative fraction (FNF) for LSIL+ slides was approximately 40 times lower than the cytotechnologist-only FNFs, and this improvement was achieved-even at a no review rate of 70%.

Conclusion: The feasibility study results showed that the AutoPap System location-guided screening process can triage slides accurately and enhance the overall accuracy of slide diagnosis. The combination of location-guided rescreening and AutoPap primary screening could improve the accuracy and workload of the laboratory.