Cytology as a screening tool for anal squamous intraepithelial lesion for HIV positive men: 10-year experience in an inner city hospital

A comprehensive review of anal cancer-with a special focus on anal cytology

The diagnosis of anal cancer is relatively uncommon, but its incidence has been steadily increasing in high-risk populations. In the 2001 Bethesda System for Reporting Cervical Cytology, anal cytology was introduced as a component. Since then, it has been recognized as a potential tool for screening anal cancer, often in conjunction with high-resolution anoscopy. There are notable similarities between anal cancer and cervical cancer, including the causative role of human papillomavirus. However, there are also significant differences, particularly in terms of disease prevalence. Anal cytology may be used as a primary screening test, and in the event of abnormalities, patients are subsequently directed for high-resolution anoscopy. However, the best approach for anal cancer screening is yet to be determined and uniformly implemented. This comprehensive review article provides an in-depth analysis of the epidemiology and incidence of anal precursor and malignant lesions. It explores the various methods of sample procurement, preparation, interpretation (including sensitivity and specificity), and reporting terminology in anal cytology. The article also addresses the significance of concurrent high-risk human papillomavirus screening in anal cytology and its role in screening programs. Furthermore, it discusses the follow-up, prevention, and subsequent management strategies for anal cancers. By synthesizing current knowledge in these areas, this review aims to provide a comprehensive understanding of anal cytology and its implications in the early detection, prevention, and management of anal neoplasia and cancer.

Anal dysplasia in adolescent and young adult men who have sex with men: a single-center retrospective and descriptive study (2010-2020)

Objective

There are limited studies evaluating anal cytology results or the prevalence of anal human papiloma virus in adolescent and young adult (AYA) men who have sex with men (MSM). The purpose of this study was to review anal cytology screening results and determine whether abnormal findings resulted in completion of anoscopy in AYA MSM (13-26 years old).

Patients and Methods

This was a retrospective study evaluating 84 anal Papanicolaou screening results among 36 AYA MSM patients aged 13-26 years who had an anal Papanicolaou test completed at an outpatient Adolescent/Young Adult Medicine Practice at Boston Children's Hospital, an urban, nonprofit, academic, free-standing children's hospital, from January 1, 2010, to December 31, 2020.

Results

The findings of anal Papanicolaou screening included atypical squamous cells of undetermined significance (ASCUS) (37%), negative for squamous intraepithelial lesion (31%), inability to read (21.3%), and low-grade squamous intraepithelial lesion (10.8%). Most patients who had ASCUS results were referred for anoscopy (n = 28, 90.3%), and of those referred only 6.5% (n = 2) completed an anoscopy. Of those with low-grade squamous cell intraepithelial lesion results, 88.9% (n = 8) were referred for anoscopy, and among those who were referred, only 3.3% (n = 3) had completed an anoscopy.

Conclusion

This study showed that there were abnormalities in cytology when anal Papanicolaou test screening was performed in this population, and the completion rates for anoscopy were low.

Programmed Death Ligand-1 Expression Is Associated With Poorer Survival in Anal Squamous Cell Carcinoma

Context.—

Upregulation of programmed death ligand-1 (PD-L1), an immunoregulatory protein, is associated with an adverse outcome in several malignancies. Very few studies have evaluated PD-L1 expression in invasive anal squamous cell carcinoma (ASCC).

Objective.—

To assess PD-L1 expression in patients with ASCC and correlate it with clinicopathologic factors and clinical outcomes.

Design.—

Fifty-one cases of ASCC were immunostained for PD-L1. PD-L1 expression by combined positive score and tumor proportion score was correlated with age, gender, HIV status, HIV viral load, CD4 count, stage, and outcomes. Kaplan-Meier curves for overall survival were plotted and compared using the log-rank test. Cox regression analysis was performed to identify significant prognostic factors (2-tailed P < .05 was considered statistically significant).

Results.—

PD-L1 was positive in 24 of 51 cases (47%) by combined positive score and in 18 of 51 (35%) by tumor proportion score. The median cancer-specific survival and 5-year overall survival were significantly lower in PD-L1+ patients. Age, gender, HIV status, HIV viral load, stage, and cancer progression were not significantly different between the two groups. CD4 count of more than 200/μL was significantly higher in PD-L1+ patients. PD-L1+ status remained statistically significant for worse overall survival on multivariate analysis.

Conclusions.—

PD-L1+ status is an independent adverse prognostic factor for overall survival in ASCC. This study highlights the potential of PD-L1 targeted therapy in better management of ASCC.

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.