A Comparative Analysis of Diagnostic Performance and Cytomorphologic Features Between Newly Developed WellPrep® and SurePath™ in Serous Effusion Cytology.

Introduction: Whereas liquid-based cytology (LBC) is often the preferred method in gynecological and non-gynecological cytopathology compared to conventional preparation, it does have several limitations. This study aims to evaluate the diagnostic accuracy and specific cytomorphologic characteristics of the newly developed WellPrep^® (WP) in comparison with SurePath™ (SP) in serous effusion cytology.

Materials and methods: A total of 178 body cavity effusion samples were collected, which were divided and further processed using both WP and SP methods. The LBC slides of the cases were independently evaluated regarding their cytomorphologic features by three pathologists. Among them, the diagnosis of 66 cases (42.6%) was confirmed as non-neoplastic or malignant using a combination of histopathological, clinical, and/or radiological follow-up. Statistical analysis was conducted to assess the diagnostic concordance and differences in selected cytomorphologic features between the two LBC methods.

Results: WP demonstrated diagnostic performance comparable to SP, with a concordance rate of 75.7% (kappa = 0.659; Spearman's ρ = 0.920). Furthermore, the diagnostic accuracy measures tested were not different between WP and SP. No case processed with WP or SP showed suboptimal slide quality. For cytomorphologic features, cellular degeneration was less frequently observed in WP than in SP. SP showed more even cellular distribution and better preservation of architectural patterns. SP also more frequently exhibited prominent nucleoli, cytoplasmic vacuoles, and signet ring cell features.

Conclusion: WP offers comparable slide quality and diagnostic accuracy with SP in serous effusion cytopathology. However, more research using larger patient cohorts would provide more evidence regarding WP.