Evolution of Pap testing at a community hospital—A ten year experience

Authors

  • Keith V. Nance M.D.

    Corresponding author
    1. Medical Director of Cytology, Rex Hospital, Raleigh, North Carolina
    2. Adjunct Associate Professor of Pathology, The University of North Carolina School of Medicine, Chapel Hill, North Carolina
    • Department of Pathology, Rex Hospital, 4420 Lake Boone Trail, Raleigh, NC 27607-7505
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  • Dr. Nance is on the Speaker's Bureau for TriPath Imaging, Inc.

  • Presented in part at the 53rd annual scientific meeting of the American Society of Cytopathology, November 4–9, 2005, San Diego, CA.

Abstract

Over a 10-year period the Pap program at our community hospital laboratory progressed from the use of 100% conventional smears to predominantly ThinPrep® (TP) and then to nearly 100% SurePath® (SP). During this period the annual Pap volume grew from less than 20,000 to nearly 50,000. This retrospective review focuses on improvements in high-grade squamous intraepithelial lesion (HSIL) detection rates and specimen adequacy rates during the 10-year period.

The laboratory database was used to identify 310,080 Pap test records between 1995 and 2004 inclusive. Pap type differences in HSIL detection rates and specimen adequacy rates were examined using the Cochran–Mantel–Haenszel test, with year as the stratification variable. The Breslow–Day test was used to evaluate the consistency of differences across the years. The overall results are summarized below in tabular format.

Results of Combined 10-Year Data for Total Number of Cases, HSIL Rate, and Unsatisfactory Specimen Rate by Pap Method are given:

Table  . 
Pap MethodTotal PapsTotal % HSILTotal % Unsat
Conv Smear128,6300.280.30
ThinPrep®88,5750.380.64
SurePath®92,8750.500.17

HSIL detection rates were significantly higher for liquid-based Pap tests compared with conventional smears (P < 0.0001). In addition, SP was associated with higher HSIL detection rates than TP with an estimated common odds ratio (OR) of 1.37 (95% confidence interval (CI), 1.10 − 1.71; P = 0.005), and higher specimen adequacy compared with TP or conventional Pap methods (P < 0.0001). Diagn. Cytopathol. 2007;35:148–153. © 2007 Wiley-Liss, Inc.

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