#11 - Rapid Prescreen of Cervical Liquid Based Cytology
Preparations. Results of a Study in an Academic
Medical Center
Mary Ann Pedigo, William J. Frable, Celeste N. Powers, Cheryl Yarrell, Becky
Ortiz, Mary E. Clark and Tameka Ebron.
Virginia Commonwealth University Medical Center
Richmond, Virginia

None
Introduction
CLIA 88 Requirements for QC – 10% of Negatives
Interesting Alternative
Rapid Prescreen of all GYN Cytology Cases
Brimo F, Renshaw AA, Deschenes M,
Charbonneau M, Auger M.
Improvement in the routine screening
performance of cytotechnologists over times: a
study using rapid prescreening.
Cancer Cytopathol. 2009;117:311-317.
Rapid Prescreen of all GYN Cytology Cases
Brimo F, Renshaw AA, Deschenes M, Charbonneau M, Auger M.
All slides rapid prescreen – 11 cytotechnologists
Analysis of two eight month periods
Divided into two Groups of Cytotechnologists
Routine screening sensitivity of > 95%
Routine screening sensitivity of < 95%
ASCUS is Threshold – Final determination by Cytopathologist
Rapid Prescreen of all GYN Cytology Cases
Brimo F, Renshaw AA, Deschenes M, Charbonneau M, Auger M.
Conclusions
Improved over all performance
May play a role in improving performance for CTs with
< 95% routine screening performance
Unanswered Questions
Did knowledge of the study bias the results?
Did the increased detection relate to real disease?
Interesting Alternative
Rapid Prescreen of all GYN Cytology Cases
Dudding N, Hewer EM, Lancucki L, Rice S.
Rapid screening: a comparative study.
Cytopathology. 2001 Aug;12(4):235-48.
Three methods – Step – Turret – Random Whole Slide
Applies to conventional smears
Step
Turret
RAPID SCREENING STUDY*
12 Study Sites
Time (Sec)
30
60
30
30
60
60
30
30
60
60
120
120
Technique
Turret
Turret
Step
Step
Step
Step
Random
Random
Random Whole
Random Whole
Random Whole
Random Whole
Total slides in Test Sets 1200 slides
1080 Negatives – 120 False negatives
10 LGSIL
7 Glandular Abnormalities
103 HGSIL
Used Two Test Sets – High and Low Prevalence of Abnormals
High Prevalence between 5 -13 abnormals – randomly placed
Low Prevalence between 0 – 2 abnormals – randomly placed
Participants used their method of rapid screening – reported
Negative
Review – requires further review
Abnormal – definitely abnormal
Interpretation of Review or Abnormal considered success
Findings and Conclusions
The step technique is significantly more sensitive
60 or 120 seconds identifies more abnormals than 30
seconds
There are large differences in individual performance
Beyond 50 slides performance falls off significantly
Analysis of 28 slides missed by more than 50% of
the participants
Demonstrated random distribution of findings for
missed abnormals
Idea is Not New
Simon TR, Ricci A. Testing Screening Time. Transactions of
The 5th Annual Meeting of the Intersociety Cytology Council
August Georgia, 1957.
4184 Cases – 2 slides each – 2 minutest per slide
Considered Adequate
Normal
Requiring Further Review
4046
3484
562
Missed Cases from Adequate Group
5
Abnormals from Requiring Further Review
17
Error Rate of First Screen
5/567 (8.8%)
Sensitivity Combined Screen
77.0%
Sensitivty of 2 Minute Screen
56.4%
Materials and Methods-Current Study
Study Length
- 14 months
Case per day – 20 sequentially numbered
Replaced in same order for routine
screening
All Surepath
Technique – Random
Length of screening – 60 seconds
Cytotechnologists selection – random
Terminology
Negative
Needs review
Epithelial Cell Abnormality
LGSIL Threshold
Materials and Methods-Current Study
Prescreen data tabulated
Compared to the laboratories
routine screen – same time period
Compared to laboratories QC screen
comparable time frame
Results – Prescreen
Total Cases Prescreened
Negative
712
642
(Includes 4 Unsat)
Epithelial Cell Abnormality
26
(LGSIL or Worse)
Needs further Review
44
Results – Routine Screening
Rapid Screened as Negative
642
Negative on Routine
Abnormal for Review
537
105
Pathologist review
Results – Routine Screening
Pathologist review
Negative Reactive
ASCUS
LGSIL
ASC-H
Other (endometrials over 40)
Unsatisfactory
Actinomyces present
Malignant melanoma
105
41
31
17
1
8
4
2
1
Routine Laboratory QA Program
LIS random selection 10% negatives
Any Patient with Prior Cytology or History
of Abnormal
Average QA is 29% of Cases
Results, comparable time frame – 2008
4045/13,767
Rescreened
Epithelial Cell Abnormality 0.9%(37cases)
Comparative Error Rates
Prescreen
for LGSIL and above
50/712 (7.0%)
19/712 (2.6%)
Routine QA
for LGSIL and above
37/4045 (0.9%)
21/4045 (0.5%)
Conclusions
1.Rapid Prescreen did not prove as
reliable as our routine QA program
2. Whether the above would be true if
only a random sample of 10% that
includes some high risk cases as
mandated by CLIA 88 remains
undetermined in this study.