Cervical Cytologic Smears in Pap Solution vs ThinPrep: Smear Characteristics and Diagnostic Agreement

Background: The Pap smear has brought about a dramatic improvement in the prevention of cervical cancer in women worldwide. In an effort to decrease the occasional false negatives in the Pap smear and further increase the screened population, ThinPrep Pap Test (TP), a fluid-based cytology collection method, has been developed. With preservation of claimed advantages of TP, we have developed a Pap test solution for manual preparatory process and compared our manually processed fluid-based Pap smear with TP to identify cytologic similarities and differences between the two methods. Methods: Cervical swipes of 204 patients were prospectively collected in the 'Pap solution' and also in PreservCyt solution for TP. Diagnoses and smear characteristics were compared. Results: The diagnoses of the paired smears agreed in 190 of the 204 cases (93.1%). The smear characteristics regarding overall cellularity and background cellularities were similar in the two methods and the stainability of the cells was virtually the same. Conclusions: The 'Pap solution' has similar performance characteristics as TP in many aspects. With its advantages of cost-effectiveness and easier preparatory process, the 'Pap solution' can match previously implemented thin layer preparation.