Symposium part 1: Should the Bethesda System terminology be used in diagnostic surgical pathology?: Point

Diagnosing Anal Squamous Intraepithelial Lesions With and Without p16: An Interobserver Variability Study

OBJECTIVE

Morphologic diagnosis and grading of anal squamous intraepithelial lesions (ASILs) are challenging. In this study, we investigated interobserver variability and p16 utility in accurately grading anal SIL.

MATERIALS AND METHODS

Six pathologists evaluated the degree of SIL on hematoxylin and eosin slides from 146 anal biopsies, followed by the review of both p16 and hematoxylin and eosin slides in cases where p16 was previously performed. κ was calculated in the following 4 ways: (A) 4-tiered diagnosis (negative for SIL [NSIL], anal intraepithelial neoplasia [AIN 1, AIN 2, AIN 3]); (B) 3-tiered diagnosis (NSIL and AIN 1 [pooled], AIN 2, AIN 3); (A) 3-tiered diagnosis (NSIL, low-grade SIL, high-grade SIL [HSIL]); and (D) 2-tiered diagnosis (no HSIL, HSIL).

RESULTS

There is only moderate agreement with a 4-tiered diagnosis with or without p16 (κ = 0.48-0.57). There is substantial agreement when AIN 2 and AIN 3 are pooled as HSIL in cases with or without p16 review (κ = 0.71-0.78). There is almost perfect agreement with a 2-tiered diagnosis of negative for HSIL and HSIL both in cases where p16 was used and where p16 was not required, with the best agreement for a 2-tiered diagnosis with concurrent p16 review.

CONCLUSIONS

This study highlights the importance of a judicious use of p16 for diagnosis. When there is no need for p16 by the Lower Anogenital Squamous Terminology guidelines, interobserver agreement was substantial to almost perfect with a 2-tiered diagnosis. However, when its use is indicated but it is not performed or reviewed, the agreement is much lower even with a 2-tiered diagnosis. Rational use of p16 will ensure diagnostic accuracy and the best possible patient care.

Three-Tiered versus Two-Tiered Classification of Squamous Dysplasia in Cervical Cytology: Results of a Follow-Up Study

OBJECTIVE

Regarding cytological findings of squamous dysplasia, a comparison was made between a three-tiered classification - low-grade squamous intraepithelial lesion (LSIL), high-grade SIL/cervical intraepithelial neoplasia 2 (HSIL/CIN2), and HSIL/CIN3 - and a two-tiered classification - LSIL and HSIL. The respective risk for CIN2+ and CIN3+ was calculated to make decisions regarding management.

METHODS

A total of 2,949 women with first-time cytologic findings of squamous dysplasia (LSIL, HSIL/CIN2, or HSIL/CIN3) between January 2013 and June 2016 were enrolled. Subsequent cytological findings and histological diagnoses were evaluated until August 2018. For each category of findings, the risk for CIN2+ and CIN3+ was determined by Kaplan-Meier estimates. The differences in risk between the cytological categories were checked for significance using the log-rank test.

RESULTS

For the categories LSIL, HSIL/CIN2, and HSIL/CIN3, the risk for CIN2+ after 12, 24, and 60 months was 3.4, 9.4, and 23.3%; 35.2, 44.8, and 59.8%; and 95.5, 97.8, and 98.9%, respectively. For CIN3+ the risk was 2.0, 5.5, and 13.5%; 28.6, 35.6, and 48.3%; 91.3, 95.6, and 97.9%, respectively. The differences in risk between the categories are highly significant, respectively (p < 0.001).

CONCLUSION

A three-tiered classification of squamous dysplasia such as the Munich Nomenclature III for cytology is suitable for risk-adapted clinical management, especially to avoid overdiagnosis and overtreatment.

Cervical cytological screening: Assessment of the Fournier ® self-sampling device in a cervical pathology outpatient clinic

BACKGROUND

The objective of this study was to investigate the performance of the Fournier(®) self-sampled device in the cytological diagnosis of cervical precursor or neoplastic lesions. The colposcopy and cervical biopsy were used as the gold standard evaluation.

METHOD

This was a case-control study performed at a cervical pathology outpatient clinic from January 2008 to October 2009. Samples were obtained through physician-collected mode before a colposcopic evaluation. Liquid-based cytology slides obtained with the device in question were stained using the Papanicolaou method and anti-p16 immunocytochemistry and were analyzed by two pathologists blind to the histological and colposcopic diagnoses.

RESULTS

Diagnostic performance for Fournier device using Papanicolaou technique was sensitivity 41.1% (Pathologist 1-P1) and 52.9% (Pathologist 2-P2) for diagnosing low-grade intraepithelial lesions; for high-grade lesions and cervical cancer, sensitivity was 68.7% (P1) and 75.0% (P2) and specificity was 81.8% (P1) and 73.8% (P2). When using the anti-p16 immunocytochemistry, the sensitivity for diagnosing low-grade intraepithelial lesions was 57.1% (P1) and 62.9% (P2), and the sensitivity was 87.5% (P1) and 93.8% (P2) for high-grade lesions and cancer. The specificity was 75.0% (P1) and 54.4% (P2).

CONCLUSIONS

These results show that when used with "blind" physician-collected cytology in an outpatient setting, the Fournier(®) device achieved a sensitivity and specificity comparable to those obtained by the Pap test traditionally collected during a speculum examination.

How our practice of histopathology, especially tumour pathology has changed in the last two decades: reflections from a major referral center in Pakistan

Continued advances in the field of histo-pathology (and cyto-pathology) over the past two decades have resulted in dramatic changes in the manner in which these disciplines are now practiced. This is especially true in the setting of a large university hospital where the role of pathologists as clinicians (diagnosticians), undergraduate and postgraduate educators, and researchers has evolved considerably. The world around us has changed significantly during this period bringing about a considerable change in our lifestyles and the way we live. This is the world of the internet and the world-wide web, the world of Google and Wikipedia, of Youtube and Facebook where anyone can obtain any information one desires at the push of a button. The practice of histo (and cyto) pathology has also evolved in line with these changes. For those practicing this discipline in a poor, developing country these changes have been breathtaking. This is an attempt to document these changes as experienced by histo (and cyto) pathologists practicing in the biggest center for Histopathology in Pakistan, a developing country in South Asia with a large (180 million) and ever growing population. The Section of Histopathology, Department of Pathology and Microbiology at the Aga Khan University Hospital (AKUH) in Karachi, Pakistan's largest city has since its inception in the mid-1980s transformed the way histopathology is practiced in Pakistan by incorporating modern methods and rescuing histopathology in Pakistan from the primitive and outdated groove in which it was stuck for decades. It set histopathology in Pakistan firmly on the path of modernity and change which are essential for better patient management and care through accurate and complete diagnosis and more recently prognostic and predictive information as well.

The Lower Anogenital Squamous Terminology Standardization project for HPV-associated lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology

The terminology for human papillomavirus (HPV)-associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) project was co-sponsored by the College of American Pathologists (CAP) and the American Society for Colposcopy and Cervical Pathology (ASCCP) and included 5 working groups; three work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted upon at the consensus meeting. The final approved recommendations standardize biologically-relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology

The terminology for human papillomavirus(HPV)–associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) Project was co-sponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology and included 5 working groups; 3 work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors, and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted on at the consensus meeting. The final, approved recommendations standardize biologically relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail the appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology

The terminology for human papillomavirus (HPV)-associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) Project was cosponsored by the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology and included 5 working groups; 3 work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors, and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted on at the consensus meeting. The final, approved recommendations standardize biologically relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail the appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

The reporting of anal cytology and histology samples: establishing terminology and criteria

Our understanding of the human papillomavirus (HPV) related cytomorphology and histopathology of the anal canal is underpinned by our knowledge of HPV infection in the cervix. In this review, we utilise cervical reporting of cytological and histological specimens as a foundation for the development of standardised and evidence-based terminology and criteria for reporting of anal specimens. We advocate use of the Australian Modified Bethesda System 2004 for reporting anal cytology. We propose the use of a two-tiered histological reporting system for noninvasive disease – low-grade and high-grade anal intraepithelial neoplasia. These classification systems reflect current understanding of the biology of HPV and enhance diagnostic reproducibility. Biomarkers such as p16INK4A may prove useful in further improving diagnostic accuracy. Standardisation is important because it will increase the value of the data collected as Australian centres develop programs for screening for anal neoplasia.

A weakly positive human papillomavirus Hybrid Capture II result correlates with a significantly lower risk of cervical intraepithelial neoplasia 2,3 after atypical squamous cells of undetermined significance cytology

OBJECTIVE

The Hybrid Capture II assay (hc2; QIAGEN, Inc) for high-risk human papillomavirus (hrHPV) is an in vitro nucleic acid hybridization assay using chemiluminescence for the qualitative detection of hrHPV DNA in cervical samples. Results are reported as a ratio of relative light units (RLUs) to a cutoff value based on a positive control. Specimens with RLU ratios of 1.0 or higher are scored positive for hrHPV. We tested the hypothesis that hrHPV positives with low-positive RLU ratios (1-10) had a lower prevalence of cervical intraepithelial neoplasia 2,3 (CIN 2,3) on histologic follow-up.

MATERIALS AND METHODS

Relative light unit ratios for 388 consecutive hrHPV-positive cervical cytologic specimens interpreted as atypical squamous cells of undetermined significance (ASCUS) were reviewed. Individual RLU ratios were compared with outcome histologic diagnosis in cases with colposcopic follow-up and tissue sampling (biopsy and/or endocervical curettage; n = 236).

RESULTS

Of 236 cases with histologic follow-up, 63 had RLU ratios in the range of 1 to 10; of these, 53 (84.1%) were negative for CIN, 7 (11.1%) had CIN 1, 1 (1.6%) had CIN of uncertain grade, and 2 (3.2%) had CIN 2,3. The difference in CIN 2,3 outcome between RLU ratios of 1 to 10 (3.2%) versus over 10 (17.3%) was significant (p =.0047). The difference in prevalence of CIN 1 was not significant (p =.67).

CONCLUSIONS

An RLU ratio of 10 or less was associated with a significantly lower prevalence of CIN 2,3 on biopsy outcome after a Pap test result of ASCUS. The much lower prevalence of underlying CIN 2,3 in patients who are weakly HPV-positive may justify modification of the management algorithm for this subset of women with ASCUS.

My approach to reporting a gastric biopsy

The protracted inflammation of the gastric mucosa induces profound changes in the microenvironment of the gastric cells. These changes modify the molecular signals that orchestrate morphogenesis and cell differentiation in the stem cells of the crypts. The expression of this adjustment to the new microenvironment is evidenced by the appearance of differentiated metaplastic cells (intestinal, bronchial-ciliated, pancreatic or (pseudo) pyloric, all deriving from the same embryological origin). The inability of stem cells to readapt to the new microenvironment may lead to genomic aberrations such as the retention of cellular products (glassy cells) or to neoplastic transformation. In this report, parameters such as gastric mucosal inflammation, Helicobacter pylori, atrophy, intestinal metaplasia and/or pseudopyloric metaplasia found in gastric biopsy specimens were individually classified according to their extension in sections as grade 1 (focal distribution in sections from individual biopsy specimens) and grade 2 (present in the entire width-distance across-in sections from individual biopsy specimen). The rationale is that a biopsy grade 2 was harvested from a larger mucosal area having that particular change. Each individual parameter gives a score, and the sum of all individual scores gives the total score. The proposed system might allow monitoring the results of treatment in follow-up biopsies. Divergent clinical results in the frequency/incidence of gastritis (including body-autoimmune gastritis), of H pylori strains, of various metaplasias and neoplasias, in disparate geographical regions substantiate the conviction that these parameters are much influenced by the environment. This knowledge is crucial, considering that environmental diseases are theoretically preventable.

Pathologic audit of 164 consecutive cases of vulvar intraepithelial neoplasia

There are 2 types of vulvar intraepithelial neoplasia (VIN): warty-basaloid and differentiated. Differentiated VIN is uncommon and seldom diagnosed prior to carcinoma and, traditionally, is not graded. There are currently 3 grading systems for warty-basaloid VIN: the World Health Organization (WHO) 3 grade system of VIN 1-3, a 2 grade system of low and high grade vulvar intraepithelial lesions, and the revised International Society for the Study of Vulvovaginal Disease (ISSVD) classification which has no grading of VIN. According to the ISSVD, VIN 1 should be abolished and VIN 2 and 3 combined into a single category, simply termed warty-basaloid VIN. To determine the best system for grading warty-basaloid VIN and learn more about differentiated VIN, we reviewed the pathology of 164 consecutive women with VIN. Of these, 134 (82.3%) had warty-basaloid VIN, 29 (18.2%) had differentiated VIN, and 1 had both. Of warty-basaloid VIN cases, 4 had VIN 1, 13 VIN 2, and 118 VIN 3 when graded according to the WHO. All VIN 1 occurred in condylomata acuminata. VIN 2 and 3 were distinguished only by degree of abnormality. Differentiated VIN was diagnosed before SCC in only 7 cases (26.7%). Because the only VIN 1 cases seen were in condylomata acuminata and because VIN 2 and 3 were difficult to distinguish and there appears little clinical reason to do so, our study supports the ISSVD proposal that VIN 1 be abolished and VIN 2 and 3 be combined. There needs to be more clinical awareness of vulvar conditions, so that differentiated VIN is biopsied before cancer has supervened.

Biology and evolution of cervical squamous intraepithelial lesions: a hypothesis with diagnostic prognostic implications

Recent advances in the understanding of HPV-associated cervical squamous intraepithelial lesions, specifically with respect to HPV DNA integration into basal cervical epithelial cells, need to be incorporated into strategies for diagnosing and classifying these lesions. The biology and evolution of HPV-associated cervical squamous intraepithelial lesions is reviewed, along with recent developments using tyramide-based in situ hybridization and MIB-1 immunoreactivity. It is proposed that HPV DNA integration into the basal cells of cervical squamous epithelium precedes the transformation of low-into high-grade lesions. The HPV DNA tyramide-based in situ hybridization system may prove to be a powerful diagnostic/prognostic tool in this regard. It is also proposed that the presence of mitoses (especially atypical forms) in the upper layers may be a discriminatory hallmark in the morphologic distinction between low- and high-grade lesions. Further, since the biologic changes manifest between these two lesions are reflected in their respective phenotype, it appears plausible to adopt the Bethesda System two-tiered/binary classification of LGSIL and HGSIL for histopathologic diagnoses.