Comparative study of the ThinPrep Pap test and conventional cytology results in a Canadian cohort
Article first published online: 21 MAR 2006
Volume 17, Issue 2, pages 73–81, April 2006
How to Cite
Duggan, M. A., Khalil, M., Brasher, P. M. A. and Nation, J. G. (2006), Comparative study of the ThinPrep Pap test and conventional cytology results in a Canadian cohort. Cytopathology, 17: 73–81. doi: 10.1111/j.1365-2303.2006.00340.x
- Issue published online: 21 MAR 2006
- Article first published online: 21 MAR 2006
- Accepted for publication 13 February 2006
- ThinPrep Pap test;
- conventional Pap test;
- comparison study;
- clinical follow-up
Objective: To compare the frequency of Pap test results in a prospective series of direct to vial ThinPrep tests to a cohort of conventionally prepared tests. To follow-up all test results for a minimum of 2 years and assess performance based on this outcome.
Methods: All women presenting for either routine screening or colposcopic examination in 2001 were enrolled in the ThinPrep cohort. A similar, population of conventionally prepared tests was extracted from the year 2000 laboratory data. Information on all concurrent and follow-up cervical specimens over the ensuing 2 years was retrieved.
Results: The ThinPrep cohort comprised 2288 Pap tests and the conventional, 2211. The frequency of normal [within normal limits (WNL) and benign cellular changes (BCC)] results in the ThinPrep cohort was 6% lower and the frequency of abnormal [≥atypical squamous cells of undetermined significance (ASCUS)] results was 6.8% higher. Respective ThinPrep and conventional cohort results were 1156 (51%) and 1291 (58%) WNL, 625 (27%) and 561 (25%) BCC, 101 (4%) and 65 (3%) ASCUS, 21 (1%) and 2 (0.1%) atypical glandular cells of undetermined significance, 301 (13%) and 224 (10%) low-grade squamous intraepithelial lesion (LSIL), and 74 (3%) and 40 (2%) high-grade SIL (HSIL) (P < 0.0001). Follow-up was available for nearly 80% of each cohort. LSIL or higher was confirmed in 57.5% (n = 266) of the abnormal ThinPrep and 60.9% (n = 190) of the abnormal conventional tests. The ThinPrep yield of confirmed tests however was almost 50% higher than the conventional test.
Conclusion: In this population, ThinPrep was superior to the conventional Pap test.