Automatic failure in gynecologic cytology proficiency testing. Results from the College of American Pathologists proficiency testing program

Low-Grade Squamous Intraepithelial Lesion or High-Grade Squamous Intraepithelial Lesion? Concordance Between the Interpretation of Low-Grade Squamous Intraepithelial Lesion and High-Grade Squamous Intraepithelial Lesion in Papanicolaou Tests: Results From the College of American Pathologists PAP Education Program

Context.—

Obtaining diagnostic concordance for squamous intraepithelial lesions in cytology can be challenging.

Objective.—

To determine diagnostic concordance for biopsy-proven low-grade squamous intraepithelial lesion (LSIL) and high-grade squamous intraepithelial lesion (HSIL) Papanicolaou test slides in the College of American Pathologists PAP Education program.

Design.—

We analyzed 121 059 responses from 4251 LSIL and HSIL slides for the interval 2004 to 2013 using a nonlinear mixed-model fit for reference diagnosis, preparation type, and participant type. We evaluated interactions between the reference diagnosis and the other 2 factors in addition to a repeated-measures component to adjust for slide-specific performance.

Results.—

There was a statistically significant difference between misclassification of LSIL (2.4%; 1384 of 57 664) and HSIL (4.4%; 2762 of 63 395). There was no performance difference between pathologists and cytotechnologists for LSIL, but cytotechnologists had a significantly higher HSIL misclassification rate than pathologists (5.5%; 1437 of 27 534 versus 4.0%; 1032 of 25 630; P = .01), and both were more likely to misrepresent HSIL as LSIL (P < .001) than the reverse. ThinPrep LSIL slides were more likely to be misclassified as HSIL (2.4%; 920 of 38 582) than SurePath LSIL slides (1.5%; 198 of 13 196), but conventional slides were the most likely to be misclassified in both categories (4.5%; 266 of 5886 for LSIL, and 6.5%; 573 of 8825 for HSIL).

Conclusions.—

More participants undercalled HSIL as LSIL (false-negative) than overcalled LSIL as HSIL (false-positive) in the PAP Education program, with conventional slides more likely to be misclassified than ThinPrep or SurePath slides. Pathologists and cytotechnologists classify LSIL equally well, but cytotechnologists are significantly more likely to undercall HSIL as LSIL than are pathologists.

False-positive Papanicolaou (PAP) test rates in the College of American Pathologists PAP education and PAP proficiency test programs: evaluation of false-positive responses of high-grade squamous intraepithelial lesion or cancer to a negative reference diagnosis

CONTEXT

In cytology proficiency testing (PT), participants fail for incorrectly interpreting a high-grade squamous intraepithelial lesion or cancer (HSIL+) Papanicolaou test result as negative. This penalty may lead to a false-positive interpretation of negative slides as HSIL+ to avoid failure.

OBJECTIVE

To investigate factors related to false-positive responses in a PT versus an educational environment.

DESIGN

We analyzed 420,079 responses from 9414 validated negative reference slides in the College of American Pathologists Interlaboratory Comparison Program in Gynecologic Cytopathology (PAP Education) and compared them with responses from the Gynecologic Cytology Proficiency Testing Program for the percentage of false-positive (HSIL+) interpretations in each of 7 negative subcategories. We evaluated the influence of preparation type (ThinPrep, SurePath, and conventional Papanicolaou test), participant type (pathologist or cytotechnologist), and program time interval (preproficiency test or PT) on a false-positive response.

RESULTS

Reference diagnosis and participant type, but not preparation type, were statistically correlated to false-positive responses. The interaction between program time interval and participant type was also significant. Pathologists had higher rates of false-positive results on preproficiency test (1.2% [800 of 68,690]) than they did on PT (0.8% [993 of 129,857]). Cytotechnologists had no differences between program time intervals (preproficiency, 0.9% [515 of 63,281] versus PT, 1.0 [1231 of 121,621]; P = .91). Negative subcategories frequently mistaken for HSIL+ were reparative changes (4.7% [427 of 9069]), atrophic vaginitis (1.8% [18 of 987]), and negative for intraepithelial lesion or malignancy (1.2% [2143 of 178,651]), but during PT, false-positive rates were significantly increased only for the negative for intraepithelial lesion or malignancy and herpes simplex virus (P < .001).

CONCLUSIONS

Pathologists had lower false-positive rates in the Gynecologic Cytology Proficiency Testing Program than they did in PAP Education, but participants were more likely to report a false-positive response (HSIL+) for negative for intraepithelial lesion or malignancy and herpes simplex virus in the Gynecologic Cytology Proficiency Test Program.

The impact of the Clinical Laboratory Improvement Amendments of 1988 on cytopathology practice: a 25th anniversary review

The Clinical Laboratory Improvement Amendments of 1988 were passed into law on October 31, 1988; regulations implementing this law have had a dramatic impact on the practice of cytology as well as the operations of the entire laboratory. Articles in the popular press followed by congressional hearings exposed faulty laboratory practices, with false-negative Pap tests being a major focus. The impact of this law on the cytology profession is reviewed in this paper. We discuss the response by professional organizations and laboratories to proposed regulations, including formation of consortium groups, development of interlaboratory comparison programs, and more stringent laboratory accreditation and inspection procedures. Public perceptions related to false-negative Pap tests and the litigation crisis are reviewed, as well as the development of new technologies that would improve test accuracy. Finally, the role of the Clinical Laboratory Improvement Advisory Committee in advising the government on laboratory regulations and cytology proficiency testing is discussed. Many of the regulations have promoted quality practices and cytology accuracy, but others have proven relatively inflexible and may have blocked innovation.

The role of proficiency testing in ensuring quality: findings from the College of American Pathologists Gynecologic Cytopathology Quality Consensus Conference working group 3

CONTEXT

Implementation of proficiency testing for gynecologic cytology was delayed 20 years because of challenges addressing the subjective nature of cytologic interpretation and replicating normal working conditions. Concern remains regarding test scoring, slide validation, test environment, and other issues. How these test results are, or should be, used in quality management has never been explored.

OBJECTIVE

To provide information on good laboratory practices for gynecologic cytology proficiency testing based on findings from the College of American Pathologists' survey-based project funded by the Centers for Disease Control and Prevention.

DATA SOURCES

An expert working group evaluated results from a Web-based, national laboratory survey plus responses from follow-up questions and findings from the literature. The group created statements on good laboratory practices pertinent to proficiency testing and its role in quality management, which were discussed and voted on at a consensus conference.

CONCLUSIONS

Two-thirds of laboratories report having an individual with an unsuccessful proficiency testing score. More than 90% did not initiate any remedial action for 1 or 2 unsuccessful tests; 84% of laboratories reported they actively monitored results from proficiency testing, but most laboratories did not initiate any remedial action for cytotechnologists (81.4%; 376 of 462) or pathologists (87.7%; 405 of 462) who passed a proficiency test but who did not score 100%. Proficiency testing pass-fail rates should be monitored globally for the laboratory and for each individual. Proficiency testing slides should be prescreened by cytotechnologists for pathologists who are not primary screeners. Remedial action should not be required for a passed, but imperfect, test. No remedial action is required for an unsuccessful, first proficiency test result before retesting.