Screening for precancerous anal lesions with P16/Ki67 immunostaining in HIV-infected MSM

DNA high-risk HPV, mRNA HPV and P16 tests for diagnosis of anal cancer and precursor lesions: a systematic review and meta-analysis

Background

Anal cancer prevention has two critical points: the incidence rate is several fold higher for some groups, such as people living with human immunodeficiency virus (HIV) and men who have sex with men (MSM), and there is not a well-defined guideline for its screening. This systematic review evaluates the accuracy of DNA HRHPV (high-risk human papillomavirus), mRNA HPV, DNA HPV16 isolated and p16 staining biomarkers in anal canal smears for identifying anal intraepithelial neoplasia (AIN) 2 or 3, summarised as anal high-grade squamous intraepithelial lesions (aHSIL), and cancer.

Methods

We searched the MEDLINE, Cochrane Library and Embase electronic databases as well as Grey literature to identify eligible papers published up to 31st July 2022. This systematic review and meta-analysis included observational studies comparing biomarker tests to histopathology after HRA (High-resolution Anoscopy) as a reference standard. We (ACM, TF) analysed studies in which patients of both sexes were screened for anal cancer using DNA HRHPV, mRNA HPV, DNA HPV16 and/or p16 biomarkers. The analysis was performed in pairs, for instance AIN2 or worse (AIN2+) vs. AIN1, HPV infection and normal (AIN1-). PROSPERO CRD42015024201.

Findings

We included 21 studies with 7445 patients. DNA HR HPV showed a higher sensitivity 92.4% (95% CI 84.2-96.5), specificity 41.7% (95% CI 33.9-44.9) and AUC 0.67, followed by the mRNA HPV test, with a sensitivity 77.3% (95% CI 73.2%-80.9%), specificity 61.9% (95% CI 56.6-66.9) and AUC 0.78. DNA HPV16 showed higher specificity 71.7% (95% CI 55.3-83.8), followed by p16 test, 64.1% (95% CI 51.0-75.4); Sensitivity of DNA HPV16 was 53.3% (95% CI 35.4-70.3) and AUC 0.69, while p16 had a sensitivity of 68.8% (95% CI 47.9-84.1) and AUC 0.74. Subgroup analysis of MSM with HIV, with 13 studies and 5123 patients, showed similar accuracy, with a bit higher sensitivities and lower specificities. Considering the measure of the total between-study variability, mRNA HPV tests showed the smallest area of the 95% prediction ellipse, 6.0%, influenced by the low logit sensitivity, 0.011. All other groups of tests exceed 50% prediction ellipse area, which represent a high heterogeneity.

Interpretation

Our findings suggested that DNA HR HPV can be a useful tool for screening for aHSIL and anal cancer if followed by biomarker with a higher specificity. As an isolated test, mRNA HPV had better performance.

Funding

There was no funding source for this study.

Microbiome-derived cobalamin and succinyl-CoA as biomarkers for improved screening of anal cancer

Human papillomavirus can cause preinvasive, high-grade squamous intraepithelial lesions (HSILs) as precursors to cancer in the anogenital area, and the microbiome is suggested to be a contributing factor. Men who have sex with men (MSM) living with human immunodeficiency virus (HIV) have a high risk of anal cancer, but current screening strategies for HSIL detection lack specificity. Here, we investigated the anal microbiome to improve HSIL screening. We enrolled participants living with HIV, divided into a discovery (n = 167) and validation cohort (n = 46), and who were predominantly (93.9%) cisgender MSM undergoing HSIL screening with high-resolution anoscopy and anal biopsies. We identified no microbiome composition signatures associated with HSILs, but elevated levels of microbiome-encoded proteins producing succinyl coenzyme A and cobalamin were significantly associated with HSILs in both cohorts. Measurement of these candidate biomarkers alone in anal cytobrushes outperformed anal cytology as a diagnostic indicator for HSILs, increasing the sensitivity from 91.2% to 96.6%, the specificity from 34.1% to 81.8%, and reclassifying 82% of false-positive results as true negatives. We propose that these two microbiome-derived biomarkers may improve the current strategy of anal cancer screening.

Anal intraepithelial neoplasia: a review of terminology, differential diagnoses, and patient management

Despite the knowledge of etiological association with high-risk human papilloma viruses and high-risk patient cohorts, the incidence of anal squamous cell carcinoma has continued to rise. The known precursor lesion (in particular, high-grade squamous intraepithelial lesion) makes it amenable to screening and surveillance strategies. However, the diagnosis of anal intraepithelial neoplasia suffers from interpretation challenges leading to high interobserver variability, along with numerous differential diagnoses and lingering terminology issues. Proper treatment of anal lesions requires accurate diagnosis, and while a variety of modalities are available for treatment, the rate of recurrence remains high and each modality has its own set of side effects and complications. The aim of this review article is to outline the diagnostic considerations and provide practical tips for diagnosing anal squamous intraepithelial lesions.

A systematic review and meta-analysis of cytology and HPV-related biomarkers for anal cancer screening among different risk groups

To inform optimal approaches for detecting anal precancers, we performed a systematic review and meta-analysis of the diagnostic accuracy of anal cancer screening tests in different populations with elevated risk for anal cancer. We conducted a literature search of studies evaluating tests for anal precancer and cancer (anal intraepithelial neoplasia grade 2 or worse, AIN2+) published between January 1, 1997 to September 30, 2021 in PubMed and Embase. Titles and abstracts were screened for inclusion and included articles underwent full-text review, data abstraction and quality assessment. We estimated the prevalence of AIN2+ and calculated summary estimates and 95% confidence intervals (CI) of test positivity, sensitivity and specificity and predictive values of various testing strategies, overall and among population subgroups. A total of 39 articles were included. The prevalence of AIN2+ was 20% (95% CI, 17-29%), and ranged from 22% in men who have sex with men (MSM) living with HIV to 13% in women and 12% in MSM without HIV. The sensitivity and specificity of cytology and HPV testing were 81% and 62% and 92% and 42%, respectively, and 93% and 33%, respectively for cytology and HPV co-testing. AIN2+ risks were similar among those testing positive for cytology, HPV, or co-testing. Limited data on other biomarkers (HPV E6/E7 mRNA and p16/Ki-67 dual stain), suggested higher specificity, but lower sensitivity compared with anal cytology and HPV. Our findings provide important evidence for the development of clinical guidelines using anal cytology and HPV testing for anal cancer screening.

Automated evaluation of p16/Ki-67 dual stain cytology as a biomarker for detection of anal precancer in MSM living with HIV

BACKGROUND

Human papillomavirus (HPV)-related biomarkers such as p16/Ki-67 "dual stain" (DS) cytology have shown promising clinical performance for anal cancer screening. Here, we assessed the performance of automated evaluation of DS cytology to detect anal precancer in men who have sex with men (MSM) living with human immunodeficiency virus (HIV).

METHODS

We conducted a cross-sectional analysis of 320 MSM with HIV undergoing anal cancer screening and high-resolution anoscopy (HRA) between 2009-2010. We evaluated the performance of automated DS based on a deep-learning classifier compared to manual DS evaluation to detect anal intraepithelial neoplasia (AIN) grades 2 and 3 (AIN2+) and AIN3. We evaluated different DS-positive cell thresholds quantified by the automated approach and modeled its performance compared to other screening strategies in a hypothetical population of MSM with HIV.

RESULTS

Automated DS had significantly higher specificity (50.9% vs. 42.2%, p=0.0004) and similar sensitivity (93.2% vs. 92.1%) for detection of AIN2+ compared to manual DS cytology. HPV testing with automated DS triage was significantly more specific (56.5% vs. 50.9%, p=0.0003) with the same sensitivity (93.2%) compared to automated DS alone. In a modeled analysis assuming a 20% AIN2+ prevalence, automated DS detected the most precancers compared to manual DS and anal cytology (186,184, and 162, respectively) and had the lowest HRA referral per AIN2+ detected (3.1,3.5, and 3.3, respectively).

CONCLUSIONS

Compared to manual evaluation, automated DS cytology detects the same number of precancers with lower HRA referral.

Evaluation of HPV-Related Biomarkers in Anal Cytological Samples from HIV-Uninfected and HIV-Infected MSM

Men who have sex with men (MSM) harbor the highest risk for anal carcinoma, mainly caused by Human Papillomavirus (HPV). The use of HPV-related biomarkers in the screening for this neoplasia is still debated. We assessed the association between high-risk (hr)HPV DNA, HPV16/18 DNA, hrHPV E6/E7 mRNA, and p16/Ki-67 with cytological abnormalities (any grade) and high-grade intraepithelial lesions (HSIL) in HIV-uninfected and HIV-infected MSM. Overall, 150 cytological samples in PreservCyt (Hologic), with a negative to HSIL report, were analyzed for hrHPV DNA, hrHPV E6/E7 mRNA, and p16/Ki-67 using the Linear Array (Roche), Aptima (Hologic), and CINtec^® PLUS (Roche) assays. In HIV-infected MSM, positivity for all the biomarkers significantly increased with the cytological grade. In both populations, the association of hrHPV E6/E7 mRNA and p16/Ki-67 positivity with HPV16 did not differ significantly compared to hrHPVs other than HPV16. In HIV-uninfected MSM, the odds of having an HSIL increased approximately six times for the p16/Ki-67 positive cases. In HIV-infected individuals, all the biomarkers showed a significant association with HSIL, except for hrHPV DNA, with the strongest association observed for p16/Ki-67. The odds of HSIL increased almost 21 times in those positive for this biomarker. Our results encourage further investigation on the use of p16/Ki-67 dual staining in anal cancer screening for HIV-uninfected and HIV-infected MSM.

Comparison of two sample collection devices for anal cytology in HIV-positive men who have sex with men: Cytology brush and Dacron swab

OBJECTIVE

HIV-positive men who have sex with men (MSM) are a vulnerable group for anal cancer (AC), a cancer with a well-described precursor lesion, which can be detected early in screening programs using anal liquid-based cytology (aLBC). We aim to compare two aLBC sample collection devices: cytology brush (CB) and Dacron swab (DS).

METHODS

Retrospective analysis of two consecutive study periods, the first using CB and the second DS. Participants underwent an aLBC, a human papillomavirus (HPV) DNA test and a high-resolution anoscopy (HRA), and a biopsy was performed for suspicious lesions. The sensitivity and specificity of aLBC, area under the receiver operating characteristic (ROC) curve (AUC), and concordance between cytology and HRA were assessed using Cohen's kappa coefficient.

RESULTS

A total of 239 participants were enrolled (CB group, 120; DS group, 119). aLBC was benign in 46% of samples, and high-grade squamous intraepithelial lesion (HSIL) was detected in 11.7%. Prevalence of biopsy-proven HSIL was 15.3%. No differences in cytological and histological results were observed between the groups. aLBC-HRA concordance was weak for benign results (CB group, k = 0.309; DS group, k = 0.350) as well as for HSIL (k = 0.321 and 0.387, respectively). Sensitivity and specificity were 100% and 51.4%, respectively, in the CB group and 88% and 54.3% in the DS group (AUC = 0.711 and 0.759, respectively, P-value = .514). Representation of the transformation zone (TZ) was adequate in 83.3% of samples in the CB group and 50.4% in the DS group (P-value <.001).

CONCLUSION

Our data suggest that both devices had similar accuracy to detect anal HSIL, although samples collected with CB are more likely to have an adequate TZ representation, the presence of which could be an indicator of sample quality.

Exploiting the Microbiota for the Diagnosis of Anal Precancerous Lesions in Men Who Have Sex With Men

BACKGROUND

While the microbiota has been associated with HPV malignant transformation, it is unclear whether anal bacteria could improve the low specificity of anal cytology for the screening of high grade intraepithelial squamous neoplasia (HSIL).

METHODOLOGY

We recruited MSM undergoing anal cytology and high-resolution anoscopy. We assessed the microbiota composition from fecal samples and cytobrush anal samples using 16SrDNA sequencing in subjects with and without biopsy-proven HSIL (bHSIL). We selected bacterial biomarkers based on their linear discriminant analysis (LDA). We assessed their predictive performance using logistic regression and bootstrap resampling.

RESULTS

We included 128 individuals, 47 (36.7%) with bHSIL and 99 (77.3%) with HIV. We detected 40 potential predictors of bHSIL. Ruminococcaceae NK4A214 group, Alloprevotella genus, Prevotella melanonigenica and Ruminococcaceae UCG-014 were the most predictive of bHSIL. From 35 false-positive cytologic results, the combination of these four biomarkers with the anal cytology reclassified to true negative 33 (94%) individuals and showed good diagnostic performance (AUC 0.805, 95%CI 0.728 - 0.882).

CONCLUSIONS

We found anal-associated bacteria indicative of a higher risk of precancerous anal lesions, which combination was highly specific. The microbiota could be developed as a complementary diagnostic tool to overcome the limitations of the current screening strategy for anal cancer.

The Diagnostic Value of p16/Ki67 Dual Immunostaining for Anal Intraepithelial Neoplasia: A Meta-Analysis

The p16/Ki67 dual immunostaining was performed on anal cytology specimens; this is an anal cancer screening method. A literature search was performed in the BioMed Central, Cochrane Library, Embase, Google Scholar, and PubMed electronic databases for relevant articles. We included studies that discussed the efficacy of p16/Ki67 dual immunostaining for detecting anal intraepithelial neoplasia (AIN). Studies that calculated the diagnostic efficacy on a per-patient basis were included. We excluded review articles, case series, and studies that did not provide sufficient information. We extracted data on true positive, true negative, false positive, and false negative from the included studies to generate pooled sensitivity, specificity, and diagnostic odds ratio (DOR). All analyses were performed with a random-effects model using MetaDiSc 1.4 and MetaDTA. The meta-analysis produced a pooled sensitivity of 0.63 (95% CI: 0.34, 0.86) and specificity of 0.65 (95% CI: 0.46, 0.81) for p16/Ki67 dual immunostaining in detecting AIN. The pooled DOR was 3.26 (95% CI: −0.29, 6.82). A subgroup analysis of HIV-infected men who have sex with men (MSM) demonstrated a pooled sensitivity of 0.75 (95% CI: 0.28, 0.96). p16/Ki67 dual immunostaining might have a higher sensitivity for detecting AIN in HIV-infected MSM. p16/Ki67 dual immunostaining might be more sensitive in HIV-infected MSM and has higher specificity compared to human papillomavirus testing among this high-risk group. p16/Ki67 dual immunostaining might be an adjuvant and potential triage test for anal cytology in anal cancer screening.

Effects of first-line antiretroviral therapy on the CD4/CD8 ratio and CD8 cell counts in CoRIS: a prospective multicentre cohort study

BACKGROUND

A low CD4/CD8 ratio during antiretroviral therapy (ART) identifies people with heightened immunosenescence and increased risk of mortality. We aimed to assess the effects of integrase strand transfer inhibitor (INSTI)-based, protease inhibitor-based, or non-nucleoside reverse transcriptase inhibitor (NNRTI)-based first-line ART on long-term CD4/CD8 ratio recovery.

METHODS

This prospective cohort study included 13 026 individuals with HIV registered in the Spanish HIV Research Network (CoRIS) cohort recruited from 45 Spanish hospitals. We included HIV-positive people who started triple ART (two nucleoside reverse transcriptase inhibitors [NRTI] with a NNRTI, protease inhibitor, or INSTI) and had HIV RNA suppression within 48 weeks. We used piecewise linear mixed models adjusted for potential confounders to compare longitudinal changes in the CD4/CD8 ratio between people receiving three different types of ART. We used Cox proportional-hazard models to compare the times to CD4/CD8 normalisation between the treatment groups, using cutoff ratios of 0·4, 1·0, and 1·5.

FINDINGS

6804 individuals contributing 37 149 persons-years and 37 680 observations were analysed; median follow-up was 49 months (IQR 22-89). INSTI-based ART was associated with greater CD4/CD8 gain (change per year compared with INSTI was coefficient -0·07 [95% CI -0·08 to -0·06] for NNRTI and was -0·08 [-0·09 to -0·08] for protease inhibitors). Differences were observed from the first year of therapy and were driven by changes in both CD4 and CD8 cell counts. Subanalyses at different time periods suggested that these differences were driven by changes during the first year of ART without significant differences in the adjusted CD4/CD8 ratio trajectories after the second year of ART (change per year compared with INSTI was coefficient -0·03 [95% CI -0·05 to -0·13] for NNRTI and was -0·06 [95% CI -0·08 to -0·04] for protease inhibitors). Although no differences in the time until CD4/CD8 normalisation at a cutoff ratio of no less than 0·4 were reported between any of the groups, compared with the INSTI group, both the NNRTI and protease inhibitor groups showed lower rates of normalisation at cutoff ratios of 1·0 or more (adjusted hazard ratio 0·80 [95% CI 0·72-0·89] for the NNRTI group and 0·79 [0·69-0·89] for the protease inhibitor group), and 1·5 or more (0·79 [0·65-0·95] for the NNRTI group and 0·78 [0·64-0·97] for the protease inhibitor group). No differences were found between the different integrases in the time until CD4/CD8 normalisation. Subanalyses adjusted for the backbone NRTIs and allowing observations after virological failure yielded similar results.

INTERPRETATION

This study provides new evidence that reinforces the positioning of INSTI-based therapies as a first choice and underlines the importance of analysing the effects of therapeutic interventions on biomarkers linked with morbidity and mortality beyond the plasma HIV RNA and the CD4 cell counts.

FUNDING

Spanish AIDS Research Network (Instituto de Salud Carlos III), European Development Regional Fund "A way to achieve Europe".

The Accuracy of Anal Swab-Based Tests to Detect High-Grade Anal Intraepithelial Neoplasia in HIV-Infected Patients: A Systematic Review and Meta-analysis

Background

The incidence of high-risk human papillomavirus (HR-HPV)–induced anal cancer is increasingly problematic among HIV-positive patients. Anal cancer is preceded by precursor lesions, anal intraepithelial neoplasia (AIN). AIN detection requires high-resolution anoscopy, a cumbersome and time-consuming procedure. We aggregated evidence on anal swab–based tests to detect AIN in HIV-positive patients.

Methods

We searched MEDLINE and EMBASE for cross-sectional studies on AIN detection with anal cytology, HR-HPV DNA detection, HPV E6/E7 mRNA analysis, and P16INK4a and Ki-67 immunostaining. Summary estimates of sensitivity and specificity were calculated using bivariate logistic regression. Cytology was reported using the terms squamous intra-epithelial lesion (SIL) for AIN and high-grade SIL (HSIL) for high-grade AIN (HGAIN).

Results

We included 22 studies. Using cytology with a cutoff of any SIL to detect HGAIN, we detected a sensitivity of 82% (95% CI, 74%–87%) and specificity of 45% (95% CI, 44%–66%); with the cutoff of HSIL, the sensitivity was 44% (95% CI, 45%–67%) and the specificity was 79% (95% CI, 69%-87%). The sensitivity of HPV DNA to detect HGAIN was 91% (95% CI, 82%–95%) and the specificity was 27% (95% CI, 21%–33%). For MSM, the positive predictive value (PPV) of cytology with a cutoff of any SIL was 36% (95% CI, 23%–50%) and the negative predictive value (NPV) was 87% (95% CI, 78%–93%), whereas cytology with a cutoff of HSIL had a PPV of 62% (95% CI, 50%–73%) and an NPV of 78% (95% CI, 65%–87%). The PPV of HR-HPV DNA detection was 37% (95% CI, 20%–57%) and the NPV was 87% (95% CI, 79%–93%).

Conclusions

Given its sensitivity, cytology with a cutoff of any SIL could be considered as a triaging method, whereas cytology with a cutoff of HSIL had better specificity and could be used for quality assurance. HR-HPV DNA detection had poor specificity and PPV, making it unsuitable for triage.

Determinants of high-grade anal intraepithelial lesions in HIV-positive MSM

OBJECTIVE

To assess determinants for histologically proven high-grade anal intraepithelial lesions (hHSIL) in HIV-positive men who have sex with men (MSM), a population at high-risk of HPV-related anal cancer.

DESIGN

APACHES is a prospective study of anal HPV and related-lesions in 513 HIV-positive MSM aged at least 35 years in six centres across France.

METHODS

At baseline, participants underwent high-resolution anoscopy (HRA) with biopsy of suspicious lesions, preceded by anal swabs for liquid-based cytology, p16/Ki67 immunostaining, and HPV DNA. hHSIL diagnosis was established by histopathological review panel consensus, and determinants assessed by logistic regression.

RESULTS

Baseline hHSIL prevalence was 10.4% and did not differ significantly by age, sexual behaviour or HIV/immunodeficiency markers. hHSIL prevalence was significantly elevated in participants who smoked (ORadj = 2.6, 95% CI 1.3-5.5) or who, in concurrent anal swabs, had ASCUS/LSIL (3.6, 95% CI 1.4-9.3) or ASC-H/HSIL (22.2, 95% CI 6.8-72.6) cytologic abnormalities, p16/Ki67 dual positivity (3.4, 95% CI 1.5-7.5), or non-HPV16 HR (13.0, 95% CI 1.7-102), but most notably, HPV16 (46.3, 95% CI 6.1-355) infection. Previous diagnosis of low-grade (2.3, 95% CI 1.0-5.4) or high-grade (3.8, 95% CI 1.5-9.9) anal lesion also conveyed higher hHSIL risk. After controlling for patient-specific determinants, there remained significant centre-specific effects, most clearly in higher risk groups (HPV16-positive participants: 31.3% hHSIL in centres A-D versus 5.1% in centres E and F, P < 0.01).

CONCLUSION

Anal cytology and HPV16 infection are potentially useful determinants of hHSIL risk in HIV-positive MSM, but HIV/immunodeficiency-related variables appear not to be. Controlling for patient-specific hHSIL determinants highlights variability in HRA practice across diverse clinical settings and the need for better standardization of this difficult procedure.

Strategies for screening and early detection of anal cancers: A narrative and systematic review and meta-analysis of cytology, HPV testing, and other biomarkers

Anal cancer incidence and mortality have been increasing over the past decade. Although the incidence in the general population remains low, it is much higher in certain subgroups, including those living with human immunodeficiency virus and men who have sex with men. Approximately 90% of anal squamous cell cancers are caused by infection with carcinogenic human papillomavirus (HPV). Given the common etiology between anal and cervical carcinogenesis, screening for anal cancer has been proposed in certain high-risk populations using strategies adapted from cervical cancer prevention. In this review, the authors discuss important differences in anal and cervical cancer regarding the populations at risk, disease natural history, and clinical procedures and outcomes that need to be considered when evaluating strategies for anal cancer screening. They also performed a systematic review and meta-analysis of the performance of anal cytology, anal HPV testing, and various biomarkers for the detection of anal precancers and cancers. The implications of these performance estimates are summarized in the context of risk-based screening and management of anal precancers, and important research gaps are highlighted that need to be addressed to fully understand the benefits and harms of anal cancer screening. Cancer Cytopathol 2018. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.