Longitudinal evaluation of interobserver and intraobserver agreement of cervical intraepithelial neoplasia diagnosis among an experienced panel of gynecologic pathologists.
ABSTRACT Histologic diagnoses of cervical intraepithelial neoplasia grades 2 and 3 (CIN 2/3) are the key end points in clinical trials that evaluate the efficacy of a prophylactic quadrivalent human papillomavirus vaccine against cervical cancer. Adjudication of end points uses a panel of 4 pathologists. Quality control slides (n=185) from a nonclinical trial study with preestablished gold standard CIN diagnoses were used to characterize the panel's agreement on CIN diagnoses and monitor performance longitudinally. At 3-month intervals over 2 years, 1 of 6 different batches of quality control slides (n=30-31) was included with clinical trial slides for independent review by each of the 4 panelists. Unweighted kappas (kappa) were estimated within each panelist pair by dichotomizing the diagnoses as CIN+ versus non-CIN+ (including normal, unsatisfactory, and atypical immature metaplasia) or CIN 2/3+ versus non-CIN 2/3+ (including normal, unsatisfactory, atypical immature metaplasia, and CIN 1). Quadratic weighted kappa was calculated within each panelist pair using 4 diagnostic categories: normal, CIN 1, CIN 2, and CIN 3 or worse. Substantial interobserver agreement was observed (weighted kappa=0.765 to 0.865). Agreement with weighted kappa=0.779 to 0.887 was observed between the individual panelists and the gold standard, which is almost perfect agreement by Landis-defined categories. Intraobserver agreement was very high (weighted kappa=0.756 to 0.883). Some fluctuation in intraobserver and interobserver agreement was observed over the study period but there was no decreasing time trend. These data indicate that the interpretation of histologic end points used in the quadrivalent vaccine clinical trial program is highly valid and reliable.
- [Show abstract] [Hide abstract]
ABSTRACT: The use of high-resolution digital images of histopathology slides as a routine diagnostic tool for surgical pathology was investigated. The study purpose was to determine the diagnostic concordance between pathologic interpretations using whole-slide imaging and standard light microscopy. Two hundred fifty-one consecutive surgical pathology cases (312 parts, 1085 slides) from a single pathology service were included in the study after cases had been signed out and reports generated. A broad array of diagnostic challenges and tissue sources were represented, including 52 neoplastic cases. All cases were digitized at ×20 and presented to 2 pathologists for diagnosis using whole-slide imaging as the sole diagnostic tool. Diagnoses rendered by the whole-slide imaging pathologists were compared with the original light microscopy diagnoses. Overall concordance between whole-slide imaging and light microscopy as determined by a third pathologist and jury panel was 96.5% (95% confidence interval, 94.8%-98.3%). Concordance between whole-slide imaging pathologists was 97.7% (95% confidence interval, 94.7%-99.2%). Five cases were discordant between the whole-slide imaging diagnosis and the original light microscopy diagnosis, of which 2 were clinically significant. Discordance resulted from interpretive criteria or diagnostic error. The whole-slide imaging modality did not contribute to diagnostic differences. Problems encountered by the whole-slide imaging pathologists primarily involved the inability to clearly visualize nuclear detail or microscopic organisms. Technical difficulties associated with image scanning required at least 1 slide be rescanned in 13% of the cases. Technical and operational issues associated with whole-slide imaging scanning devices used in this study were found to be the most significant obstacle to the use of whole-slide imaging in general surgical pathology.Human pathology 05/2012; 43(10):1739-44. · 2.81 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Background Bivalent and quadrivalent human papillomavirus (HPV) vaccines are now licensed in several countries. Furthermore, clinical trials examining the efficacy of a nonavalent vaccine are underway. We aimed to compare the potential population-level effectiveness of the bivalent, quadrivalent, and candidate nonavalent HPV vaccines.Methods We developed an individual-based, transmission-dynamic model of HPV infection and disease in a population stratified by age, gender, sexual activity, and screening behavior. The model was calibrated to highly stratified sexual behavior, HPV epidemiology, and cervical screening data from Canada.ResultsUnder base case assumptions, vaccinating 12-year-old girls (70% coverage) with the bivalent (quadrivalent) vaccine is predicted to reduce the cumulative incidence of anogenital warts (AGWs) by 0.0% (72.1%), diagnosed cervical intraepithelial neoplasia lesions 2 and 3 (CIN2 and -3) by 51.0% (46.1%), and cervical squamous cell carcinoma (SCC) by 31.9% (30.5%), over 70 years. Changing from a bivalent (quadrivalent) to a nonavalent vaccine is predicted to reduce the cumulative number of AGW episodes by an additional 66.7% (0.0%), CIN2 and -3 episodes by an additional 9.3% (12.5%), and SCC cases by an additional 4.8% (6.6%) over 70 years. Differences in predicted population-level effectiveness between the vaccines were most sensitive to duration of protection and the time horizon of analysis. The vaccines produced similar effectiveness at preventing noncervical HPV-related cancers.Conclusions The bivalent vaccine is expected to be slightly more effective at preventing CIN2 and -3 and SCC in the longer term, whereas the quadrivalent vaccine is expected to substantially reduce AGW cases shortly after the start of vaccination programs. Switching to a nonavalent vaccine has the potential to further reduce precancerous lesions and cervical cancer.CancerSpectrum Knowledge Environment 10/2012; · 14.07 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The purpose of this study was to develop and analytically and functionally validate a new human papillomavirus (HPV) in-situ hybridization (ISH) assay and to determine whether the use of this assay combined with hemotoxylin and eosin (H&E) staining could potentially improve the diagnostic accuracy of interpreting cervical intraepithelial neoplasia (CIN) in human cervical tissue specimens. An automated HPV ISH assay was developed using probes that targeted the broad spectrum of HPV genotypes most commonly associated with CIN. In an exploratory study, tissue sections (n=118) were stained with H&E alone and H&E with HPV ISH and evaluated by 6 general surgical pathologists. Results were compared with diagnoses established by expert pathologists on H&E alone. The change in specificity (diagnosis of no-CIN) and sensitivity (diagnosis of CIN) using H&E plus HPV versus H&E alone was determined. The HPV ISH assay detected 21 HPV genotypes and demonstrated no cross-reactivity to Epstein-Barr virus, cytomegalovirus, herpes simplex virus (HSV)-1, HSV-2, or human placental DNA. The assay detected HPV in a range of 1 to 600 copies on CaSki, HeLa, and SiHa xenografts. Use of this assay with H&E staining improved the average diagnostic specificity of the surgical pathologists from 68.5% to 89.9% (P<0.001), with fewer false-positive CIN 1 results (122 vs. 39). The diagnostic sensitivity was similar for assessments made with H&E alone and those made with HPV plus H&E (93.1% vs. 93.6%). In conclusion, a new automated broad-spectrum HPV ISH assay combined with H&E-stained slides contributed to better ascertainment of CIN than H&E staining alone.International journal of gynecological pathology: official journal of the International Society of Gynecological Pathologists 09/2012; 31(6):588-95. · 2.07 Impact Factor