Results of the implementation of liquid-based cytology - SurePath in the Ontario screening program

BACKGROUND. The objective of the current study was to evaluate the adequacy and detection rates of SurePath after its implementation in Ontario. METHODS. The detection and adequacy rates of the SurePath liquid-based cytology system (SP-LBC) were calculated for manually reviewed slides of the year 2002. The adequacy and detection rates from this study group were compared with a historical conventional smear (CS) group from the same laboratories during the same period of the previous year. RESULTS. The SP-LBC study group consisted of 352,680 specimens with cytodiagnoses and the CS group included 378,990 specimens. The unsatisfactory rate for SP-LBC (0.24%) was less than that of the CS group (0.58%). The detection rate of atypical squamous cells (ASC+) by the SP-LBC group (4.69%) was greater than that of the CS group (3.81%), as was the detection rate of low-grade squamous intraepithelial lesions (LSIL+; 2.13% vs. 1.50% in the CS group). There was only a trend toward increased detection of high-grade squamous intraepithelial lesions (HSIL+) in the SP-LBC group (0.34%) relative to the CS group (0.31%), because the detection rate for carcinoma by SP-LBC declined. CONCLUSIONS. The implementation of SP-LBC has been followed by better specimen adequacy and detection rates for ASC+, LSIL+, and a trend of increased detection of HSIL+ relative to CS practice. To determine sensitivity rates, a histopathologic database for cervical carcinoma and precancer needs to be established. (C) 2004 American Cancer Society.