Morphologic Features Which Affect Validation And Proficiency Test Performance Of BiopsyProven HSIL Pap Tests. The ASCP GYN PT & Assessment Committee

Transcription

1 Morphologic Features Which Affect Validation And Proficiency Test Performance Of BiopsyProven HSIL Pap Tests The ASCP GYN PT & Assessment Committee

2 The ASCP GYN PT & Assessment Committee Robert A. Goulart, MD, Chair Jamie L. Covell, BS, CT(ASCP), Vice-chair Thomas A. Bonfiglio, MD Mark H. Stoler, MD William J. Frable, MD Carol M. Filomena, MD Syed Ali, MD Judith L. Burns, CT(ASCP) Mark Dieterich, MD Ronald D. Luff, MD, MPH Donna K. Russell, MS, CT(ASCP), HT, CMIAC Alia Salhadar, MD Maria A. Friedlander, MPA, CT(ASCP) Raja M. Gidwani, MD (Fellow Member) Enid Boeding, MD (Resident Member) Rhonda L. Metzler, SCT(ASCP), Senior Manager

3 Conflicts of Interest The Authors Have No Conflicts of Interest to Disclose.

4 Introduction Before Pap tests are entered into the American Society for Clinical Pathology (ASCP) GYN Proficiency Test (PT) program: 100% target diagnosis agreement amongst 5 committee (3 MD, 2 CT) referee reviewers Minimum performance of 90% target diagnosis agreement after 40 individual reads (validation) Biopsy confirmation (SIL and cancer cases)

5 Introduction Despite this vigorous process, a small subset of validated slides does not perform as well in actual testing.

6 Introduction When the target diagnosis agreement for any slide level falls below 90%: Immediately removed from the pool of active test slides Similarly, a small subset of slides is removed late in the validation process (between reads) What can we learn from the morphologic features of these cases?

7 Introduction Comparison of the morphologic features of "high" vs. "low" performing slides could provide information concerning subtle differences that result in less reproducible interpretations: Target diagnostic category of HSIL Both clinically significant and relatively common Inter-cytopathologist HSIL diagnostic agreement relatively poor (Diagn Cytopathol 16(1):87, 1997)

8 Conventional Pap Studies Features associated with Conventional Pap smear discrepancies in biopsy-proven CIN II/III cases in PT (Arch Pathol Lab Med 129(6):733, 2005): Fewer dysplastic cells (less than 50) Lack of large dysplastic cells Lack of keratinization Hypochromasia (not correlated with performance) Non-PT Conventional Pap studies: Processing artifacts (air-drying) Excessive blood/obscuring inflammation Sampling/rare abnormal cells

9 Liquid-Based Pap Studies Features associated with ThinPrep Pap test discrepancies in biopsy-proven CIN II/III cases in PT (Arch Pathol Lab Med 128(7):746, 2004): Fewer dysplastic cells (less than 250) Non-PT ThinPrep Pap tests (Hong Kong Med J 14(4):292, 2008): Fewer abnormal cells Fewer cells with koilocytic change Less pronounced hyperchromasia

10 Materials and Methods Two HSIL ThinPrep Pap test groups Each 30 cases (slides) High performers (HP): 90% target diagnosis agreement throughout the validation process and during active testing Low performers (LP): failed validation or were soon removed from the active test pool

11 Materials and Methods Two HSIL ThinPrep Pap test groups Each slide was re-evaluated by five committee reviewers in a blinded fashion Slides were also reviewed for overall technical quality Staining (fading)

12 Materials and Methods Review characteristics: Predominant HSIL cell pattern (groups vs. single cells) Cell groups (< or > 10) Single HSIL cells (< or > 20) Relative number of LSIL cells Nuclear membrane irregularity Hyperchromasia Nuclear chromatin granularity (coarse vs. fine) Nucleoli (present/absent in majority of HSIL cells) N/C ratio Atrophy Atypical keratinized squamous cells Inflammation Organisms (Trichomonas and Candida) Endometrial cells

13 Materials and Methods Review characteristics: Reviewers instructed to note which slides they perceived might perform poorly A consensus interpretation (majority) was assigned for each category Statistical evaluation (Fisher s exact test)

14 Materials and Methods Predominant HSIL Cell Pattern

15 Materials and Methods Nucleoli Present

16 Results 59/60 slides were considered technically satisfactory Single slide within the LP group deemed technically unsatisfactory due to stain fading

17 Results Review characteristics: Predominant HSIL cell pattern (groups vs. single cells) Cell groups (< or > 10) Single HSIL cells (< or > 20) Relative number of LSIL cells Nuclear membrane irregularity Hyperchromasia Nuclear chromatin granularity (coarse vs. fine) Nucleoli (present/absent in majority of HSIL cells) N/C ratio Atrophy Atypical keratinized squamous cells Inflammation Organisms (Trichomonas and Candida) Endometrial cells

18 Results Review characteristics: Predominant HSIL cell pattern (groups vs. single cells) Cell groups (< or > 10) Single HSIL cells (< or > 20) Relative number of LSIL cells Nuclear membrane irregularity Hyperchromasia Nuclear chromatin granularity (coarse vs. fine) Nucleoli (present/absent in majority of HSIL cells) N/C ratio Atrophy Atypical keratinized squamous cells Inflammation Organisms (Trichomonas and Candida) Endometrial cells

19 Results Statistically significant difference in criteria Number of cell groups (>/= 10) Number of single cells (>/= 20) Presence of nucleoli All associated with the Good Performer subset of cases Prediction of slide performance

20 Conclusions An increased quantity of HSIL cells, either in cell groups or as single cells, correlated with completion of the validation process and high field PT performance (reproducibility of HSIL target diagnosis). A high level of performance was also seen in the slides with nucleoli present in the majority of HSIL cells, albeit an infrequent finding.

21 Conclusions Although only one-half of the 30 low performing cases could be predicted by the reviewers, designation as such was highly accurate.

22 Conclusions Clinical Correlates In routine Pap test sign-out, attention to cases with rare potential HSIL cells (both in single cells and cell groups), particularly if nucleoli are present, should increase sensitivity for detection of CIN II/III. Further supporting evidence of ASC-H Stresses importance of locator skills

23 Thank you The ASCP GYN PT & Assessment Committee