Factors affecting the cytology outcome of Pap smears – a brief approach to internal quality control in private cytopathology laboratory practice
Abstract:We evaluated the effect of intrauterine device (IUD), patient age and hormone replacement therapy (HRT) on cytology outcome in Pap smears together with the important IQC procedures: 1) manual double-screening by cytotechologists, and 2) retrospective senior pathologist review during 1996–1999. The results from primary double-screening (119 of 87,409 Pap smears) showed an excellent interobserver correlation. The estimation of hormonal effects showed higher incidence of disagreements (p=0.013) in patients <47 yr. Some individual trends were found in the assessments of both cellular atypia (p=0.012) and Papanicolaou classification (p=0.018). The IUD had no influence on the accuracy when the degree of inflammatory reaction was evaluated (p>0.050), but showed an adverse effect on the estimation of cellular atypia (p=0.001). HRT distinctly equalized the entire sample material, since fewer disagreements were found in the age groups <47 yr and >47 yr when estimating the hormonal effects (p=0.013), inflammatory reaction (p=0.044) or cellular atypia (p=0.006) compared to those without HRT. The continuous cytopathologist supervision had a positive impact on the accuracy of hormonal effect estimation during the 4 years. The senior cytopathologists' reviews (354 of 87,409 Pap smears) showed mutually good interobserver correlation, and diagnostic conclusions of the same specimens differed only slightly between the cytopathologists. We found these state-of-the-art cytopathological IQC procedures to be effective and fit-for-purpose when evaluating hormonal effects, inflammatory reaction and cellular atypia.
Document Type: Original Article
Affiliations: 1: Medix Laboratories Ltd., Department of Pathology, Espoo, Finland, 2: Helsinki University Hospital, Department of Pathology, Transplantation Laboratory, 3: University of Helsinki, Department of Public Health
Publication date: 2001-10-01