Rescreen effect in conventional and PAPNET screening: observed in a study using material enriched with positive smears.
OBJECTIVE
To study the rescreen and PAPNET effects on enriched material derived from smears screened routinely using PAPNET and conventional microscopy.


METHODS
A series of 432 smears (containing 122 atypical squamous cells of undetermined significance [ASCUS] plus 44 at least dysplastic squamous intraepithelial lesion-positive [SIL+] ones), screened routinely with the conventional method, were rescreened using the PAPNET system. Another series of 461 smears (containing 140 ASCUS + 52 SIL+ ones) screened routinely with PAPNET were rescreened conventionally. The rescreen effect, defined as the effect of differences between the rescreen and routine screening situation, was investigated by comparing the rescreen results in both series of smears with the routine results in both series. The effect of using either method of screening was studied by comparing the PAPNET results in both series with the results of conventional screening in both series.


RESULTS
The rescreen effect was statistically significant both for a higher number of smears classified as negative (less than ASCUS) and a higher number of smears classified as high grade SIL or more. PAPNET-assisted screening resulted in a significantly higher number of smears classified as high grade SIL+, although for this latter finding there is an unexplained significant difference between conventional and PAPNET-screened cases in the changes made by the cytopathologist in the cytotechnologists' diagnoses.


CONCLUSIONS
The rescreen effect should not be ignored when enriched material is used.
van Ballegooijen
M
M
Department of Public Health, Faculty of Medicine, Erasmus University, Rotterdam, The Netherlands.
Beck
S
S
Boon
M E
ME
Boer
R
R
Habbema
J D
JD
D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006801:Humans; D019044:Image Cytometry; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008403:Mass Screening / Q000379:methods*; D015588:Observer Variation; D011230:Precancerous Conditions / Q000175:diagnosis / Q000473:pathology*; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis / Q000473:pathology*; D014626:Vaginal Smears / Q000379:methods*; D002578:Uterine Cervical Dysplasia / Q000175:diagnosis / Q000473:pathology