Anal-rectal cytology: A review

Screening of Anal HPV Precancerous Lesions: A Review after Last Recommendations

Over the last decades, the incidence of anal cancer has increased worldwide. The discovery of the HPV virus as its primary cause and the natural progression of the disease, involving precancerous lesions, have resulted in significant interest in screening for anal cancer. The use of cytology testing, high-risk HPV DNA research, high-resolution anoscopy, and their combination has been adopted with variable success in detecting anal HPV precancerous lesions. Various studies have been carried out to evaluate the sensitivity and specificity of these techniques in different populations. High-risk populations for developing anal cancer have been identified through study of incidence and prevalence. Therefore, different scientific societies and experts worldwide have provided different recommendations for screening, but a universal approach has not yet been established. The inhomogeneity of different risk groups, the variable accessibility to specifical techniques, and the lack of data regarding the cost-benefit ratio of screening are the main problems to address in order to define a consensus guideline acceptable worldwide. The purpose of this paper is to provide a comprehensive review of the literature on HPV precancerous lesions and its screening, particularly after the release of recent recommendations.

Scattering-Based Light-Sheet Microscopy Imaging of Human Papillomavirus-Associated Squamous Lesions of the Anal Canal: A Proof-of-Principle Study

Demand for anal cancer screening is expected to rise following the recent publication of the Anal Cancer-HSIL Outcomes Research trial, which showed that treatment of high-grade squamous intraepithelial lesions significantly reduces the rate of progression to anal cancer. While screening for human papillomavirus-associated squamous lesions in the cervix is well established and effective, this is less true for other sites in the lower anogenital tract. Current anal cancer screening and prevention rely on high-resolution anoscopy with biopsies. This procedure has a steep learning curve for providers and may cause patient discomfort. Scattering-based light-sheet microscopy (sLSM) is a novel imaging modality with the potential to mitigate these challenges through real-time, microscopic visualization of disease-susceptible tissue. Here, we report a proof-of-principle study that establishes feasibility of dysplasia detection using an sLSM device. We imaged 110 anal biopsy specimens collected prospectively at our institution's dysplasia clinic (including 30 nondysplastic, 40 low-grade squamous intraepithelial lesion, and 40 high-grade squamous intraepithelial lesion specimens) and found that these optical images are highly interpretable and accurately recapitulate histopathologic features traditionally used for the diagnosis of human papillomavirus-associated squamous dysplasia. A reader study to assess diagnostic accuracy suggests that sLSM images are noninferior to hematoxylin and eosin images for the detection of anal dysplasia (sLSM accuracy = 0.87; hematoxylin and eosin accuracy = 0.80; P = .066). Given these results, we believe that sLSM technology holds great potential to enhance the efficacy of anal cancer screening by allowing accurate sampling of diagnostic tissue at the time of anoscopy. While the current imaging study was performed on ex vivo biopsy specimens, we are currently developing a handheld device for in vivo imaging that will provide immediate microscopic guidance to high-resolution anoscopy providers.

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.

Screening for precancerous anal lesions linked to human papillomaviruses: French recommendations for clinical practice

In France, about 2000 new cases of anal cancer are diagnosed annually. Squamous cell carcinoma is the most common histological type, mostly occurring secondary to persistent HPV16 infection. Invasive cancer is preceded by precancerous lesions. In addition to patients with a personal history of precancerous lesions and anal cancer, three groups are at very high risk of anal cancer: (i) men who have sex with men and are living with HIV, (ii) women with a history of high-grade squamous intraepithelial lesions (HSILs) or vulvar HPV cancer, and (iii) women who received a solid organ transplant more than 10 years ago. The purpose of screening is to detect HSILs so that they can be treated, thereby reducing the risk of progression to cancer. All patients with symptoms should undergo a proctological examination including standard anoscopy. For asymptomatic patients at risk, an initial HPV16 test makes it possible to target patients at risk of HSILs likely to progress to cancer. Anal cytology is a sensitive test for HSIL detection. Its sensitivity is greater than 80% and exceeds that of proctological examination with standard anoscopy. It is indicated in the event of a positive HPV16 test. In the presence of cytological abnormalities and/or lesions and a suspicion of dysplasia on clinical examination, high-resolution anoscopy is indicated. Performance is superior to that of proctological examination with standard anoscopy. However, this technique is not widely available, which limits its use. If high-resolution anoscopy is not possible, screening by a standard proctological examination is an alternative. There is a need to develop high-resolution anoscopy and triage tests and to evaluate screening strategies.

Conventional cytologic diagnosis of human papillomavirus-induced anal intraepithelial neoplasia: The experience of a referral center in Rio de Janeiro, Brazil

BACKGROUND

Screening of anal cancer is rarely available or performed in Brazil. This study analyzes the diagnostic performance of conventional cytology (CC) in the prevention of anal cancer in a coloproctology and gynecology outpatient clinics in a public hospital in Rio de Janeiro, Brazil.

METHODS

From 2005 to 2017, 1066 conventional cytological samples were collected. We analyze the causes of unsatisfactory samples (11.3%) and compare the cytological diagnoses of 83 samples from persons living with HIV and persons not living with HIV and in specific situations, using as the gold standard high-resolution anoscopy or histopathology in cases biopsied within 6 months after cytology.

RESULTS

The sensitivity of cytology with diagnosis of ASC-US for detection of anal intraepithelial neoplasia of any grade was 85%, specificity was 41%, positive and negative predictive values were 64% and 75%, respectively, and positive and negative likelihood ratios were 1.46 and 0.35, respectively.

CONCLUSION

Conventional cytology available in resource-limited settings is a simple, noninvasive, low-cost method that proved feasible for outpatient screening of precursor lesions of the anal canal.

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.

HPV 16 and 18 contribute to development of anal dysplasia in HIV infection irrespective of gender and sexual orientation

OBJECTIVES

The aim of the present study was too investigate prevalence and persistence of human papilloma virus (HPV) and cytological abnormalities (CAs) in the anal swabs of people living with HIV (PLWH): men who have sex with men (MSM), men who have sex with women (MSW) and women (W).

METHODS

Between March 2010 and January 2019, an anal swab for cytological and HPV genotyping tests was offered to all PLWH attending our clinic. Logistic regression analysis was conducted to identify predictors of infection.

RESULTS

In all, 354 PLWH were screened: 174 MSM, 90 MSW and 61 W. Prevalence of at least one high-risk (HR) HPV was higher in MSM (91%) and W (85%) than in MSW (77%) (P < 0.05). Cytological abnormalities were found in 21.1% of the entire population. At multivariable regression analysis a lower risk for HPV infection was found for W than for MSM [odds ratio = 0.24 (95% confidence interval: 0.115-0.513)] and for MSW than for MSM [0.37 (0.180-0.773)] and there was a significantly higher risk of CAs in PLWH with HPV 16 and 18 [3.3 (1.04-10.49)]. A total of 175 PLWH (103 MSM, 33 MSW and 26 W) had at least one follow-up visit (T1) after a median (interquartile range) follow-up of 3.6 (2.1-5.7) years. The acquisition rate of HR-HPV was high, with 66.7% of PLWH negative for HR-HPV at T0 who became positive at T1 (P < 0.001). The prevalence of CAs was stable (20.6%). A significant association between CAs at T1 and persistence of HPV-16 and/or 18 was found (P < 0.05).

CONCLUSIONS

HPV 16 and 18 are associated with the presence and development of CAs irrespective of sexual orientation.

Anal cancer screening and prevention: a review for dermatologists

The incidence of and mortality from anal cancer, predominantly squamous cell carcinoma (SCC), have been increasing since the 1980s, during an era when many common malignancies have seen decreases in mortality. Dermatologists may be more likely to see patients at an increased risk for anal SCC, such as those living with HIV, MSM and those presenting for management of anogenital warts, yet there is little guidance in the field on how to manage these patients. We underwent a project to review the evidence surrounding screening and prevention of anal SCC. HPV vaccination, the main preventative measure for anal SCC, is often underutilized and may not be effective for those most at risk. Screening methods currently include high-risk HPV and anal cytology testing, with high-resolution anoscopy (HRA) reserved for biopsy and confirmatory testing. High-risk HPV testing has been associated with high sensitivity for intraepithelial neoplasia, but low specificity in high-risk groups. Recent meta-analyses examining AIN detection using anal cytology estimate a similarly high sensitivity of 74-87%, with a relatively higher specificity (44-66%) for identifying high-grade AIN. HRA is the gold standard for diagnosis, but its accessibility and cost are deterrents from its use as a screening tool. Cervical cancer screening, initially adopted without significant evidence of its impact, has significantly decreased cervical cancer rates. The argument can be made that rates of anal SCC may also benefit from appropriate screening methods, particularly anal cytology. It is prudent for dermatologists to be aware of the methods available to them in the management of at-risk patients, the data supporting them, and the potential benefits of screening in order to counsel patients appropriately and address the increasing burden of disease.

Screening Women for Anal Cancers: Guidance for Health Care Professionals

Anal cancer is rare in the general population but is steadily increasing in incidence over the past decade especially in women. Identification and screening of women with high risk facilitates detection of anal precancer and early-stage cancer, improves survival, and potentially uses less invasive therapies compared with the conventional chemoradiation treatments used for advanced cancers. No recently published guidelines currently describe details about screening women for anal squamous cell cancer (ASCC). The available evidence supports the existence of groups of women with higher prevalence of ASCC (e.g., women with human immunodeficiency virus, immune suppression, or previous lower-genital high-grade lesion or cancer) who would likely benefit from screening with some combination of anal cytology and human papillomavirus testing. Additional research is needed to establish the cost-effectiveness and the influence of screening on ASCC mortality rates.

The interpretation of high-grade squamous intraepithelial lesion on anal cytology: a comparative analysis with the cervical Papanicolaou test

INTRODUCTION

Prior studies have shown that high-grade squamous intraepithelial lesion (HSIL) tends to be underdiagnosed on anal cytology. Our study aims to decipher the interpretative challenges of HSIL that are more specific to anal cytology specimens by comparing them to cervical Papanicolaou tests.

MATERIALS AND METHODS

One hundred cases each of anal and cervical cytology specimens with HSIL interpretation and concordant histologic follow-up were retrieved and diagnostically confirmed. Patient demographic data were obtained from the electronic medical record. The cytologic specimens were reviewed and statistically compared in terms of proportion of HSIL cells, HSIL patterns and types, and cytoplasmic area of HSIL cells (with digital image analysis). A P value of <0.05 was considered statistically significant.

RESULTS

Of the patients with anal HSIL, 97% were human immunodeficiency virus-positive and 60% were men who have sex with men. The anal cytology specimens significantly differed from the cervical ones in several respects: proportion of HSIL cells, cytoplasmic area of HSIL cells, cases with HSIL cells in syncytial groups (10 versus 57) and cases with keratinizing HSIL (45 versus 10). The P value was <0.0001 for all comparisons except for the proportion of HSIL cells (P = 0.001).

CONCLUSIONS

Anal cytologic HSIL, in contrast to its cervical counterpart, exhibits fewer abnormal cells and smaller size of the diagnostic cells with a higher percentage of keratinizing lesions. A careful scrutiny of the sample with an enhanced understanding of the morphology and better sampling may help improve the detection of anal HSIL on cytology.

Negative Predictive Value of Human Papillomavirus Testing: Implications for Anal Cancer Screening in People Living with HIV/AIDS

OBJECTIVES

People living with HIV/AIDS (PLWHA) have an increased incidence of anal squamous cell carcinoma. Since high-risk human papillomavirus (hrHPV) is the primary cause, hrHPV DNA testing may play an important role in anal cancer screening. This study aims to determine the negative predictive value (NPV) of hrHPV testing in PLWHA as well as factors that may lead to false-negative results.

METHODS

Anal swabs were collected for cytology and Cobas® 4800 HPV test for 14 hrHPV types. Patients underwent concomitant high-resolution anoscopy (HRA) examination and biopsy. High-grade squamous intraepithelial lesions (HSIL, synonymous with anal intraepithelial neoplasia AIN2 and 3) detected in Cobas-negative patients were genotyped for 22 HPV types using BioPerfectus Multiplex Real-time PCR.

RESULTS

156 PLWHA tested negative for hrHPV on anal swab samples (i.e., Cobas-negative). HRA-guided biopsy detected HSIL/AIN3 in 13 patients (8%, NPV 92%), HSIL/AIN2 in 5 patients (3%), low-grade squamous intraepithelial lesions in 82 (LSIL, 53%), or benign findings in 56 (36%). No cancer was found. The HSIL group was similar to the LSIL/benign group regarding age, gender, race/ethnicity, clinical HIV parameters, cytological diagnoses, history of receptive anal sex, and smoking (p ≥ 0.02). Genotyping HSIL tissue derived from Cobas-negative patients revealed hrHPV (n=7), possibly carcinogenic HPV53, 67, 73, 82 (n=12), or absence of hrHPV (n=4).

CONCLUSIONS

In this series, anal hrHPV DNA testing offered 92% NPV for PLWHA; in other words, a 8% risk of occult precancer remains for those who test hrHPV negative on anal swab samples.

Epidermal growth factor attenuates lingual papillae lesions in a rat model of sialoadenectomy

Salivary epidermal growth factor (EGF) plays an important role in the maintenance of the oral and gastro-esophageal mucosa. Sialoadenectomy delays healing of oral wounds and affects lingual papillae. In this work, we aimed to determine the effect of EGF deficiency induced by sialoadenectomy and evaluate the effect of exogenous EGF administration on the lingual papillae and taste buds in rats. Thirty male adult Wistar albino rats were equally divided into 3 groups; sham-operated control group, sialoadenectomy group and group of sialoadenectomy + EGF. EGF was given 8 weeks after sialoadenectomy in a dose of 1 μg /ml/day in drinking water for 2 weeks. The anterior two-thirds of the tongue was dissected and cut longitudinally into two halves; one half for light microscope and the other for electron microscope examinations. Saliva and blood were collected to determine salivary and plasma EGF. Our results revealed that sialoadenectomy significantly reduced plasma and saliva levels of EGF which resulted in severe disruption of the architecture of lingual papillae. These changes were effectively improved by the exogenous EGF administration. In conclusion, EGF supplementation reversed the effects of sialoadenectomy and restored almost normal architecture of lingual papillae and taste buds.

Anal cytology in women: Experience from a single tertiary center

INTRODUCTION

Anal cytology (AC) can be used as a screening tool for detection of anal HPV associated lesions, mainly in men who have sex with men and in immunosuppressed patients. Our aim is to review our experience with AC in women.

MATERIAL & METHODS

We have retrospectively reviewed all AC diagnosed between 2010-2017 in a single tertiary hospital (n = 644) and selected those performed in women (n = 158).

RESULTS

24.53% of AC were performed in women. 14.7% of all women were HIV positive and 56.7% referred anal intercourse. Squamous lesions were found in 27.2% of women, most of them ASCUS and LSIL (14% and 11.5%). HPV DNA was detected in 38.6% of patients, and 63.9% of them showed positivity for multiple high-risk types. Anal biopsy showed high grade lesions in 20% of biopsied patients. We observed a significant relationship between HPV status and receptive anal sex, and the association between HPV status and anal histological diagnosis tended to significance. Sensitivity, specificity, negative predictive value and positive predictive value for anal cytology were 57%; 83%; 28% and 94%, respectively. 70.9% of women had synchronous cervical cytology, and squamous cervical lesions were detected in 46.4% of the cases, most of them LSIL or ASCUS (21.4% and 15.2%). We did not confirm a significant association between cytological diagnosis of cervical and anal samples.

CONCLUSIONS

AC is less widely used in women than in homosexual men. However, women show important rates of anal lesions, regardless of their HIV status. More studies should be performed to assess the potential impact of screening protocols in this population.

Evaluation of p16/Ki-67 Dual Staining Compared with HPV Genotyping in Anal Cytology with Diagnosis of ASC-US for Detection of High-Grade Anal Intraepithelial Lesions

Introduction

Human Papillomavirus (HPV) infection is the main risk factor for anogenital cancer. The objective of this study was to compare p16/Ki-67 dual staining to HPV genotyping in anal cytology samples with an atypical squamous cell of undetermined significance (ASC-US) for the identification of high-grade squamous intraepithelial lesion (HSIL).

Methods

Anal cytology samples with an ASC-US result (n = 111) were collected from patients of a university hospital (Lyon, France) from 2014 to 2015. Cases with remaining squamous cells (n = 82) were stained using p16/Ki-67 dual staining (CINtec-Plus kit) and analyzed for HPV screening (CLART2-PCR kit) using a composite endpoint of biopsy and cytology results on follow-up specimens.

Results

Detection of HSIL on follow-up specimens (5/22 biopsies; 1/29 cytology samples) was obtained in two out of six cases with p16/Ki-17 versus. five out of six with HPV genotyping alone. Sensitivity and specificity to detect HSIL for p16/Ki-67 was 33% (95% confidence interval [CI] [4; 77]) and 49% (95%CI [34; 64]) versus. 83% (95%CI [36; 99.6]) and 13% (95%CI [5; 27]) for HPV genotyping.

Conclusion

Herein, HPV genotyping was more sensitive but less specific than p16/Ki-67 staining for the detection of subsequent HSIL in ASC-US anal cytology. A larger study is required to evaluate the combination of these biomarkers for triage.

Anal Intraepithelial Neoplasia from a Pathologists Point of View

Anal squamous cell carcinoma is a relatively rare diagnosis, but its incidence has continued to rise. Anal squamous cell carcinoma and its precursor lesion, anal intraepithelial neoplasia (AIN), are human papillomavirus (HPV)-associated squamous neoplasias. High-risk HPV subtypes cause cellular proliferation in the anal transformation zone mucosa leading to similar dysplastic changes as seen in the cervix. Unified cytologic and histologic classification systems have emerged for all HPV-associated squamous lesions of the lower anogenital tract due to recent advancements in the understanding of these lesions. P16 immunohistochemical stain, a biomarker for HPV, is recommended in the diagnosis of HPV-associated lesions. The unity of terminology will aid in communication between pathologists and clinicians, ultimately leading to improved patient care.

High Prevalence of Anal Canal High-Risk Human Papillomavirus Infection in Patients With Crohn's Disease

BACKGROUND & AIMS

The increasing incidence of anal canal carcinomas requires better knowledge on anal human papillomavirus (HPV) infection. We aimed to assess anal canal HPV infection prevalence and risk factors among patients seen at a gastroenterology department in France.

METHODS

We analyzed anal tissue samples collected from 469 consecutive patients (median age 54 years, 52% women), including 112 who received immunosuppressant therapies and 101 with inflammatory bowel disease (70 with Crohn's disease), who underwent colonoscopy examinations from April 1, 2012 to April 30, 2015. HPV was detected and genotyped using the INNO-LiPA assay, and we collected medical and demographic data from all subjects. Risk factors for any HPV, high-risk HPV (HR-HPV) and HPV16 infection were assessed by bivariate and multivariate analysis. The primary outcomes association of HR-HPV or HPV16 with medical and demographic features.

RESULTS

We detected HPV DNA in anal tissues from 34% of the subjects and HR-HPV in 18%. HPV16 was the most prevalent genotype (detected in 7%), followed by HPV51, HPV52, and HPV39. HR-HPV was detected in a significantly higher proportion of samples from women (23.1%) than men (12.8%) (P = .0035); HR-HPV and HPV16 were detected in a significantly higher proportion of patients with Crohn's disease (30.0%) than without (18.1%) (P = .005). Female sex, history of sexually transmitted disease, lifetime and past year-number of sexual partners, active smoking, and immunosuppressive therapies were independent risk factors for anal HR-HPV infection in multivariate analysis.

CONCLUSION

One third of patients who underwent colonoscopy at a gastroenterology department were found to have anal canal HPV infection. We detected HR-HPV infection in almost 20% of patients and in a significantly higher proportion of patients with Crohn's disease than without. Increasing our knowledge of HPV infection of anal tissues could help physicians identify populations at risk and promote prophylaxis with vaccination and adequate screening.

Unsatisfactory exfoliative anal cytology samples, 15-year experience with histologic, cytologic, and molecular follow-up

BACKGROUND

The incidence of anal carcinoma has risen in recent decades. Exfoliative cytology screening of selected high risk patients is performed in many centers. Unsatisfactory cytology results are frustrating to patients, clinicians, and laboratorians. The aim of this study is to ascertain outcomes of patients with non-diagnostic anal cytology.

METHODS

A retrospective review of anal cytology testing performed at the Cleveland Clinic between 01/01/2001 and 12/31/2015 was performed. All cases were received as liquid-based samples and processed as ThinPreps (Hologic, Marlborough, MA). Co-testing for HR-HPV DNA was performed using Hybrid Capture 2® (Qiagen, Germantown, MD) in the majority of patients.

RESULTS

Of 1,276 ThinPrep anal cytology samples, 130 (10%) were deemed unsatisfactory. 77% of patients were HIV positive. 85% were males. Of the unsatisfactory cases, 116 (89%) were co-tested for HR-HPV DNA. Of those, 40 patients (34%) had a simultaneous positive HR-HPV DNA. Adequate follow up cytology within a one year and a two year period revealed that 18/130 (14%) and 26/130 (20%) of patients had ASC or SIL respectively. Histologic follow-up within one and two years showed 3 patients (2%) and 8 patients (6%) with HSIL or worse.

CONCLUSIONS

High risk patients with unsatisfactory anal cytology are not "negative". At least one-third proved to be concomitantly HR-HPV DNA positive with one-fifth showing subsequent cytologic squamous abnormalities and with more than 5% being diagnosed with a high grade intraepithelial lesion within two years. Prompt repeat cytology and/or HR-HPV DNA is recommended for high risk patients with non-diagnostic cytology.

Vulvar and Anal Intraepithelial Neoplasia: Terminology, Diagnosis, and Ancillary Studies

Currently, it is recognized that there is an HPV-related and an HPV-independent pathway to developing squamous cell carcinomas (SCC) in the anus and vulva. The majority of precursor lesions and SCC in the anus and vulva are high-risk HPV-associated, with HPV16 the most common type. Given the morphologic overlap and biological equivalence of HPV-related preinvasive squamous lesions of the lower anogenital tract, a unified, 2-tiered histopathologic nomenclature is now recommended. In contrast, mutations in the TP53 gene have been associated with HPV-independent vulvar and anal SCC. A precursor lesion-differentiated or simplex vulvar intraepithelial neoplasia (dVIN)-has been identified for HPV-independent vulvar SCC but a similar lesion in the anus has not been described. Extramammary Paget disease is a nonsquamous intraepithelial lesion of the vulva and anus that may be a primary epidermotropic apocrine neoplasm or may represent secondary involvement by a synchronous/metachronous adenocarcinoma. This entity may be mimicked by squamous lesions and melanocytic lesions. Herein, we discuss the morphologic and immunohistochemical features of anal and vulvar intraepithelial neoplasia in the context of updated terminology and current understanding of disease biology.

Anal High-Grade Squamous Intraepithelial Lesions in Human Immunodeficiency Virus-Infected Men: A Study of 100 Cases With Emphasis on Cytohistologic Correlation

OBJECTIVES

Anorectal cytology (ARC) is a widely used screening tool for anal cancer in human immunodeficiency virus (HIV)-infected men who have sex with men (MSM). Its diagnostic accuracy needs to be improved, especially for high-grade squamous intraepithelial lesions (HSILs).

METHODS

Using 100 HIV+ MSM with biopsy-proven anal HSILs, we correlated histologic/cytologic findings.

RESULTS

Upon review, HSIL cells were present in 58 cytology samples and absent in 42. Positive samples were higher in cellularity and contained transformation zones ( P  < .05). Cytology was able to predict HSILs in 36%, 48%, 68%, and 78% of patients with one, two, three, and four or more high-grade lesions. HSIL cells were identified in all cytology samples initially reported as HSILs or atypical squamous cells, cannot exclude HSIL and in 34 samples reported as low-grade squamous intraepithelial lesions or less. Notably, among this last category, 15 (44%) were keratinized-type HSILs.

CONCLUSIONS

Our findings should improve the ARC detection rate for anal HSILs, helping to implement ARC as the primary screening tool for anal cancer.

Anal human papillomavirus infection: prevalence, diagnosis and treatment of related lesions

Human papillomavirus (HPV) infection is mostly asymptomatic, but may also have many diverse clinical signs encompassing benign ano-genital lesions, and carcinomas. Recently, interest has also particularly focused on anal cancer since, over the last decades, its incidence has been greatly increasing in developed countries, both in women and men and is drastically higher in specific risk groups, such as men who have sex with men (MSM) and HIV-1 infected individuals. Approximately 88% of anal cancer cases worldwide are associated with HPV infection. This review summarizes our current understanding of anal HPV infection, discussing its epidemiology and risk factors in various populations, and the state of the art in the detection of anal HPV infection and its related lesions through both cytology and histology. Finally, we discuss the clinical management and therapy for these lesions.

[Effectiveness of human papillomavirus genotyping for detection of high-grade anal intraepithelial neoplasia compared to anal cytology]

INTRODUCTION

The incidence of high-grade anal intraepithelial neoplasia (HGAIN) -with an aetiological based on high-risk types of human papillomavirus- is increasing in some high-risk groups. Screening for HGAIN includes routine anal cytology and, more recently, HPV genotyping. The main objective of this study was to determine the sensitivity and specificity of anal cytology and HPV genotyping for the detection of HGAIN.

MATERIALS AND METHODS

This is a study to determine the correlation of cytological and microbiological findings with anal biopsy findings in a cohort of patients at high risk of developing AIN referred to the department of sexually transmitted infections of the Hospital Costa del Sol, Spain, between January 2008 and December 2014.

RESULTS

Of the 151 patients subjected to screening, a total of 92 patients, all of them with the result of three screening test (anal cytology, genotyping and biopsy) were included in the study. Just under two-thirds (62%) of them were HIV-positive. The sensitivity and specificity of anal cytology to detect HGAIN were 52.8 and 85.7%, respectively (k: 0.328), and 78 and 62.8% to detect two or more HPV oncogenic genotypes (k: 0.417). The detection of oncogenic HPV genotypes allowed the identification of 23 new cases of HGAIN that had been underdiagnosed with anal cytology, with 14 cases containing at least three high-risk genotypes.

CONCLUSION

Anal cytology did not show enough sensitivity in HGAIN screening. HPV genotyping has shown to be a useful tool to detect HGAIN cases, although it could lead to an over-diagnosis as a solitary screening procedure.

The performance of anal cytology as a screening test for anal HSILs in homosexual men

BACKGROUND

Studies regarding the performance of anal cytology in which both the screening test (cytology) and the diagnostic test (high-resolution anoscopy [HRA]) are performed in all members of a screening population are rare. The authors evaluated the performance of liquid-based anal cytology in a cohort of homosexual men in Sydney, New South Wales, Australia.

METHODS

The Study of the Prevention of Anal Cancer (SPANC) is a 3-year prospective study of the natural history of anal human papillomavirus infection in homosexual men aged ≥35 years. At baseline, all participants underwent a liquid-based anal cytology test and HRA at the same clinical visit. Biopsies were obtained for histological assessment if lesions suspicious for human papillomavirus infection were visible during HRA. Using any cytological abnormality as the threshold, the sensitivity, specificity, and positive and negative predictive values were calculated against histologically diagnosed high-grade squamous intraepithelial lesions (HSILs).

RESULTS

Among 617 men recruited, the median age was 49 years (range, 35-79 years) and 35.7% were positive for the human immunodeficiency virus. Overall, the sensitivity of cytology was 83.2%, the specificity was 52.6%, the positive predictive value was 45.8%, and the negative predictive value was 86.7%. Specificity improved with increasing age (P for trend =.041). Sensitivity was significantly higher in men with >1 anal octant of biopsy-confirmed HSIL (92.9% vs 77.7%; P = .010), and in those who had ≥10 metaplastic cells present on their cytology slides (87.5% vs 70.2%; P = .007).

CONCLUSIONS

Anal cytology was found to have a higher specificity in older men while maintaining sensitivity. Sensitivity was higher among those with more extensive HSILs and men with metaplastic cells present on cytology. Cancer Cytopathol 2016;124:415-24. © 2016 American Cancer Society.

An anal cancer screening program for MSM in Italy: Prevalence of multiple HPV types and vaccine-targeted infections

BACKGROUND

Elevated HPV infection rates have been described in HIV-positive males, placing these subjects at high risk of anal neoplasia. Bivalent, quadrivalent, and nonavalent vaccines to prevent HPV infection have been developed, and recently proposed for gender-neutral immunization programs.

OBJECTIVES

In order to estimate the benefit that could be obtained by vaccination of HIV-positive men who have sex with men (MSM), we aimed at describing the frequency of multiple and vaccine-targeted HPV infections in MSM enrolled in an anal cancer screening program.

STUDY DESIGN

The anal cancer screening program was conducted between July 2009 and October 2012. Mucosal anal samples were tested for HPV DNA using MY09/MY11 PCR primers and, if positive, genotyped using the CLART2HPV Clinical Array (35HPV types).

RESULTS

A total of 220 MSM were screened and 88.6% were positive for HPV DNA: in 86.5% at least one high-risk (HR) type was found and in 13% only low-risk (LR) HPV were found. Multiple infections accounted for 84.5% of HPV DNA-positive cases and overall 160 different HPV genotype combinations were recognized (only three combinations were detected in more than one patient each). Based on strain coverage, at least one vaccine-targeted HPV type was found in 38.9%, 64%, and 78.4% of cases when considering bivalent, quadrivalent and nonavalent vaccines, respectively. At least one HR vaccine-targeted strain was found in 39% of MSM for bivalent and quadrivalent vaccines, and in 64% of cases for nonavalent prevention.

CONCLUSIONS

Anal HPV infections in unvaccinated mostly HIV-infected MSM are highly prevalent. The majority of this population has multiple infections with an extremely heterogeneous number of genotype combinations. The nonavalent vaccine could theoretically have prevented a minimum of one HR HPV type in two thirds of subjects.

HPV load and anal cytological abnormalities

OBJECTIVES

The objective of this study was to evaluate the association between estimated human papillomavirus (HPV) viral load and abnormal cytology on anal samples.

METHODS

Anal cytological samples of 42 HIV-positive patients were analysed by conventional cytology and Hybrid Capture II.

RESULTS

On cytology, 30.95% (13 of 42) anal samples were positive for cytological abnormalities, 47.61% (20 of 42) were negative and 21.42% (nine of 42) were unsatisfactory. High-risk HPV infection was more frequent in anal samples with cytological abnormalities than in negative samples (P = 0.0002, Fisher's exact test), it was detected in all samples with cytological abnormalities and in 35% (seven of 20) of the negative samples. On samples with cytological abnormalities, the median of the relative light unit/cutoff (RLU/CO) value (viral load estimate) was 10.39 (1.02-572.6) and in negative samples it was 0.51 (0.26-51.70). The median of the RLU/CO value was higher in samples with cytological abnormalities when compared with the median in negative samples (P = 0.0001, Mann-Whitney U-test) and only samples with cytological abnormalities showed RLU/CO values > 100.

CONCLUSIONS

The estimated high-risk HPV viral load is significantly higher in samples with cytological abnormalities than in negative anal samples and may be useful as an adjunct to anal cytology for triage of patients to high-resolution anoscopy and biopsy.

Screening for Anal Cancer in Women

OBJECTIVE

The incidence of anal cancer is higher in women than men in the general population and has been increasing for several decades. Similar to cervical cancer, most anal cancers are associated with human papillomavirus (HPV), and it is believed that anal cancers are preceded by anal high-grade squamous intraepithelial lesions (HSIL). Our goals were to summarize the literature on anal cancer, HSIL, and HPV infection in women and to provide screening recommendations in women.

METHODS

A group of experts convened by the American Society for Colposcopy and Cervical Pathology and the International Anal Neoplasia Society reviewed the literature on anal HPV infection, anal SIL, and anal cancer in women.

RESULTS

Anal HPV infection is common in women but is relatively transient in most. The risk of anal HSIL and cancer varies considerably by risk group, with human immunodeficiency virus-infected women and those with a history of lower genital tract neoplasia at highest risk compared with the general population.

CONCLUSIONS

While there are no data yet to demonstrate that identification and treatment of anal HSIL leads to reduced risk of anal cancer, women in groups at the highest risk should be queried for anal cancer symptoms and required to have digital anorectal examinations to detect anal cancers. Human immunodeficiency virus-infected women and women with lower genital tract neoplasia may be considered for screening with anal cytology with triage to treatment if HSIL is diagnosed. Healthy women with no known risk factors or anal cancer symptoms do not need to be routinely screened for anal cancer or anal HSIL.

Anal Pap smears and anal cancer: what dermatologists should know

Squamous epithelial cells are susceptible to infection by the human papillomavirus. Infection of squamous epithelium with oncogenic human papillomavirus types is associated with development of dysplasia and potential malignant transformation. Historically, cervical cancer has been the most prevalent human papillomavirus-induced squamous neoplasia. However, because of widespread screening via Pap smear testing, rates of cervical cancer in the United States have decreased dramatically during the past 50 years. Rates of anal cancer, in contrast, have doubled during the past 30 years. The groups at highest risk for development of anal cancer are men who have sex with men, HIV-positive patients, and patients immunosuppressed as a result of solid-organ transplantation. By detecting dysplasia before it develops into invasive cancer, anal Pap smears may be a potentially useful screening tool for anal cancer, particularly in individuals known to be at increased risk. However, at this time, sufficient data supporting the benefit of anal Pap smear screening are lacking. With insufficient evidence, no national health care organizations currently recommend the use of anal Pap smears as a routine screening test, even among high-risk groups.

Prevalence of abnormal anal cytology and high-grade squamous intraepithelial lesions among a cohort of HIV-infected men who have sex with men

BACKGROUND

The incidence of anal cancer among HIV-infected patients is higher than that in other populations. Anal high-grade squamous intraepithelial lesions are considered precursors to invasive squamous-cell carcinomas and are strongly associated to high-risk human papillomavirus infection.

OBJECTIVE

The aim of this study is to determine the prevalence of anal high-grade squamous intraepithelial lesions through screening based on cytology and high-resolution anoscopy with biopsy in a cohort of HIV-infected men who have sex with men.

DESIGN

This investigation is an observational cross-sectional cohort study.

SETTING

The study was conducted in the HIV unit of a tertiary hospital in Spain.

PATIENTS

Three hundred HIV-infected men who have sex with men participated. Physical examination led to a diagnosis of perianal squamous-cell carcinoma and high-grade squamous intraepithelial lesions in 2 patients who were then excluded.

INTERVENTIONS

Anal liquid cytology was performed. Patients with cytological abnormalities underwent high-resolution anoscopy and biopsy.

MAIN OUTCOME MEASURE

The primary outcome measured was biopsy-proven high-grade squamous intraepithelial lesions.

RESULTS

The median age was 41 ± 10.5 years. The mean and nadir CD4 cell counts were 651 ± 205 cells/mm(3) (interquartile range, 438-800) and 273 ± 205 cells/mm(3) (interquartile range, 131-362). High-risk human papillomavirus was detected in 80.9% of patients, and human papillomavirus 16 was detected in 35.9% of patients. The mean number of human papillomavirus genotypes was 4.6 ± 2.9 (CI, 2-6). Anal cytology was abnormal in 40.9% of patients (n = 122/298; interquartile range, 35.4%-46.6%). High-resolution anoscopy and biopsies were performed in 119 patients. The results of histological analyses were as follows: normal, 7.7% (n = 23); condyloma, 4.3% (n = 13); anal intraepithelial neoplasia 1, 5.7% (n = 17); anal intraepithelial neoplasia 2, 14% (n = 42); and anal intraepithelial neoplasia 3, 8% (n = 24). The overall prevalence of high-grade squamous intraepithelial lesions among patients with abnormal cytology was 54% (95% CI, 45.1%-62.8%). A diagnosis of high-grade squamous intraepithelial lesions was associated with human papillomavirus 16 and human papillomavirus 51 infection, and with detection of a higher number of human papillomavirus genotypes.

LIMITATIONS

High-resolution anoscopy was only performed in patients with abnormal cytology.

CONCLUSIONS

The prevalence of high-risk human papillomavirus infection and high-grade squamous intraepithelial lesions is high in our cohort. Physical examination enabled straightforward diagnosis of perianal high-grade squamous intraepithelial lesions and squamous-cell carcinoma in 2 patients.

Comparable performance of conventional and liquid-based cytology in diagnosing anal intraepithelial neoplasia in HIV-infected and -uninfected Thai men who have sex with men

BACKGROUND

Anal cytology has increasingly been used to screen for anal intraepithelial neoplasia (AIN) among men who have sex with men (MSM) at increased risk for anal cancer. Use of liquid-based cytology has been reported to reduce fecal and bacterial contamination and air-drying artifact compared with conventional cytology. Costs associated with liquid-based cytology, however, may limit its use in resource-limited settings.

METHODS

Anal swab samples were collected from MSM participants and used to prepare conventional and liquid-based cytology slides. Abnormal conventional cytology results triggered referral for high-resolution anoscopy and biopsy. Agreement between the 2 cytology techniques and the positive predictive value ratios of histology confirmed AIN were calculated.

RESULTS

Among 173 MSM, abnormal anal cytology was identified in 46.2% of conventional and 32.4% of liquid-based slides. The results agreed in 62.4% of cases with a κ value of 0.49 (P < 0.001). HIV-infected MSM had a 3.6-fold increased odds of having discordant anal cytology results (95% confidence interval: 1.6 to 7.8; P = 0.001) compared with HIV-uninfected MSM. Histological AIN 2 and 3 were identified in 20 MSM. The positive predictive value ratios and 95% confidence interval indicated no difference between the 2 techniques.

CONCLUSIONS

Conventional anal cytology may be a preferred option for resource-limited settings given comparable performances to liquid-based cytology for the detection of AIN, although the agreement between the 2 techniques was lower among HIV-infected MSM. Due to high prevalence of abnormal anal cytology and AIN, health systems should prepare adequate infrastructure for high-resolution anoscopy services and AIN treatment.

Screening for anal neoplasia: anal cytology - sampling, processing and reporting

Anorectal cytology (ARC) is increasingly accepted as a valid screening tool for the diagnosis of squamous intraepithelial lesions in populations at increased risk for anal cancer. As with cervical cancer screening protocols, proper patient preparation, specimen collection and specimen processing are essential for obtaining an optimal cytological sample. With attention and experience, the clinician can collect the best possible ARC specimen for laboratory evaluation. The incorporation of repeated interval anal cytology into standard surveillance practices for high-risk individuals is a valuable tool for the early detection of human papillomavirus-related anal squamous epithelial lesions and the prevention of anal squamous cell carcinomas.

Practising high-resolution anoscopy

The incidence of anal cancer is increasing in the general population among both men and women. The incidence is particularly high among men who have sex with men and HIV-infected men and women. Anal cancer is similar to cervical cancer and is associated with human papillomavirus (HPV). Anal cancer is potentially preventable through primary prevention with HPV vaccination or secondary prevention. Secondary prevention is modelled after cervical cancer, where cytology is used as a screening tool to identify women who need colposcopy. Colposcopy includes magnification of the cervix, which, along with acetic acid and Lugol's solution, is used to visualise and biopsy potentially precancerous lesions, enabling treatment before progression to cervical cancer. Anal cancer is likely preceded by high-grade anal intraepithelial neoplasia (HGAIN), and a colposcope with acetic acid and Lugol's solution may similarly be used to visualise HGAIN to permit biopsy and treatment in an effort to prevent anal cancer. To distinguish it from cervical colposcopy, this technique is called high-resolution anoscopy (HRA). Many of the features that distinguish low-grade AIN from HGAIN are similar to those of the cervix, but HRA poses several additional challenges compared with cervical colposcopy. These include uneven topography; obscuring of lesions due to haemorrhoids, folds, stool or mucus; or lesions being located at the base of folds and anal glands. Consequently, a long learning curve is typically required before becoming fully competent in this technique. The technique of HRA, its uses and challenges in prevention of anal cancer are described in this article.

HPV infection and intraepithelial lesions from the anal region: how to diagnose?

In the last years, the prevalence of HPV infection in the anal region has increased, especially in some groups like homosexual and HIV-positive people. Since this infection can be associated with the development of squamous anal cancer due to its progression from HPV infection to anal intraepithelial neoplasia (AIN) and finally to cancer, the screening and evaluation of these conditions are important. Anal cytology and high resolution anoscopy are good methods that are available and can be used. Although useful, these methods should be performed correctly and not indiscriminately in all patients. Patients for whom anal cytology screening is recommended are: HIV-infected patients, homosexuals, women who present with high-grade vulvar squamous intraepithelial neoplasia, vulvar cancer or cervical cancer. An abnormal anal cytology should be further evaluated with high resolution anoscopy.

Value of cytologic Papanicolaou smears and polymerase chain reaction screening for human papillomavirus DNA in detecting anal intraepithelial neoplasia: comparison with histology of a surgical sample

BACKGROUND

The performance of cytologic screening and its correlation with histology and polymerase chain reaction (PCR) detection of human papillomavirus (HPV) DNA have not been evaluated in populations with a low prevalence of anal intraepithelial neoplasia (AIN). The objective of the current study was to analyze the significance of abnormal smears relative to the histology and PCR detection of HPV DNA.

METHODS

A cytologic smear and a viral sample were taken in 300 consecutive patients undergoing surgery (Milligan-Morgan hemorrhoidectomy and/or fissurectomy) who gave their informed consent.

RESULTS

The cytologic smear was normal in 216 of 290 patients (74.5%). Four high-grade and 19 low-grade intraepithelial neoplastic lesions were identified. In 5 patients, high-grade lesions could not be excluded, 30 lesions were of undetermined significance, and there were 16 cellular modifications with a non-neoplastic appearance. The PCR test for HPV was positive in 18.7% of patients, and a high-risk genotype was identified in 63.6% of positive samples. Histologic examination of the surgical samples was normal in 92.3% of patients. The 23 AIN samples were distributed as follows: 13 grade 1 AIN (AIN1), 6 AIN2, and 4 AIN3. The sensitivity of cytologic smears and PCR for detecting AIN was 56% and 60.8%, respectively, and specificity was 77% and 84.5%, respectively. Combining the 2 tests increased sensitivity to 78% but decreased specificity to 68%.

CONCLUSIONS

Compared with a large surgical sample, anal cytologic Papanicolaou smears and HPV PCR exhibited sensitivity and specificity that varied, depending on the risk of HPV infection and AIN. Positive HPV DNA screening increased with AIN grade, and high-risk HPV testing was particularly helpful.

High detection rate of human papillomavirus in anal brushings from women attending a proctology clinic

OBJECTIVES

To study human papillomavirus (HPV) anal infection in anal brushings from women attending a proctology clinic, and compare results with those obtained from paired cervical brushings.

METHODS

Women attending a university hospital proctology clinic for anal conditions or as part of a screening campaign, were enrolled consecutively, excluding those reporting previous HPV-related pathologies. HPV genotypes in anal and cervical brushings were determined by sequencing and, in most cases, type-specific viral loads were measured.

RESULTS

HPV DNA was detected in 28.3% of anal brushings, with 47.4% of HPV genotypes being high risk. Cervical HPV detection was at almost the same rate but HPV status was discordant in about half those women with at least one positive specimen. Abnormal cytological findings were more common in anal than in cervical samples, in particular in the proctology outpatients. Viral load measurements excluded the existence of a multiple infection with genotypes detected in discordant anal- and cervical-paired samples and showed a significant correlation between anal and cervical paired concordant samples.

CONCLUSIONS

The high rate of HPV detection in anal brushings that is not usually related to HPV positivity in cervical brushings could provide support for offering HPV DNA tests to women attending proctology clinics.

[Japanese HIV-infected men who have sex with men screened for anal intraepithelial neoplasia]

The prevalence of and the risk factors for abnormal anal cytology among Japanese men who have sex with men (MSM) who have human immunodeficiency virus (HIV) infection have not been fully investigated up to now. We conducted a nested case-control study of 81 HIV-infected Japanese MSM treated with antiretroviral therapy at a sexuality minority affirmative clinic between April 2010 and March 2011. Results showed that 41 (50.6%) of the 81 had normal anal cytology, 13 (16.0%) atypical squamous cells, 24 (29.6%) low-grade squamous intraepithelial lesions, and 3 (3.7%) high-grade squamous intraepithelial lesions. No carcinoma cases were seen. Multivariate analysis showed abnormal anal cytology to be associated with a history of genital condyloma (OR 4.19, p = .021). We concluded that abnormal anal cytology was common among HIV-infected Japanese MSM. Effective screening and management should be planned for precancerous anal lesions.

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.

Comparative accuracy of anal and cervical cytology in screening for moderate to severe dysplasia by magnification guided punch biopsy: a meta-analysis

Background

The accuracy of screening for anal cancer precursors relative to screening for cervical cancer precursors has not been systematically examined. The aim of the current meta-analysis was to compare the relative accuracy of anal cytology to cervical cytology in discriminating between histopathologic high grade and lesser grades of dysplasia when the reference standard biopsy is obtained using colposcope magnification.

Methods and Findings

The outcome metric of discrimination was the receiver operating characteristic (ROC) curve area. Random effects meta-analysis of eligible studies was performed with examination of sources of heterogeneity that included QUADAS criteria and selected covariates, in meta-regression models. Thirty three cervical and eleven anal screening studies were found to be eligible. The primary meta-analytic comparison suggested that anal cytologic screening is somewhat less discriminating than cervical cytologic screening (ROC area [95% confidence interval (C.I.)]: 0.834 [0.809–0.859] vs. 0.700 [0.664–0.735] for cervical and anal screening, respectively). This finding was robust when examined in meta-regression models of covariates differentially distributed by screening setting (anal, cervical).

Conclusions

Anal cytologic screening is somewhat less discriminating than cervical cytologic screening. Heterogeneity of estimates within each screening setting suggests that other factors influence estimates of screening accuracy. Among these are sampling and interpretation errors involving both cytology and biopsy as well as operator skill and experience.

[AIDS Study Group/Spanish AIDS Consensus Plan Document on sexually transmitted infections in HIV-infected patients]

Sexually transmitted infections (STI) are a major public health problem. Considering their high morbidity and potential short and long term after effects, physicians must have enough knowledge on the management of these infections for a correct prevention, diagnosis and treatment. HIV infection is associated with STI, not only because they share route of transmission, but also because they lead to an increased risk of HIV transmission. In this article, we summarise the updated clinical practice guidelines, for the evaluation, management and prevention of STI in HIV-infected patients, from a panel of experts in HIV, dermatologists, proctologic surgeons, and microbiologists on behalf of the Spanish AIDS Study Group (GESIDA) and the National AIDS Plan (PNS).

Anal cancer and cervical cancer screening: key differences

Cervical cancer and anal cancer share many similarities including causation by oncogenic human papillomaviruses; however, significant differences exist in their epidemiology, risk factors, biologic behavior, management, and treatment. Although rare, the incidence of anal cancer is alarmingly high and continues to increase in high-risk populations, particularly men who have sex with men regardless of their human immunodeficiency virus (HIV) status. There are no national screening guidelines for anal cancer. Using the success of cervical cancer screening as a model, anal cancer screening approaches apply anal cytology, high-resolution anoscopy, and directed biopsy to guide treatment and management strategies. Although much has been learned about the natural history and epidemiology of anal intraepithelial neoplasia (AIN), the rate of progression of high-grade anal intraepithelial neoplasia (HGAIN) to invasive squamous cell carcinomas is not known. The impact of screening and treatment of HGAIN on morbidity and mortality from anal cancer are also unknown. Because the incidence of HGAIN and anal squamous cell carcinoma continue to increase, it is imperative to find pathways for effective screening, early detection, and therapeutic intervention. This article provides an overview of anal cancer screening while highlighting its differences from cervical cancer screening and the remaining obstacles and controversies to implementation of a successful anal cancer screening program.

Utilidade da citologia anal no rastreamento dos homens heterossexuais portadores do HPV genital

Os papilomavírus humanos (HPV) de alto risco estão fortemente relacionados à etiologia do carcinoma espinocelular (CEC) anogenital e suas lesões precursoras. O HPV-16 é o tipo mais freqüente, estando presente em até 87% dos CEC do canal anal HPV-positivo. Apesar de ser relativamente raro, vem sendo cada vez mais diagnosticado, nas últimas décadas, sobretudo em indivíduos do sexo masculino. A incidência é ainda mais elevada nos grupos considerados de risco, particularmente, os homens e as mulheres HIV-positivo e os homens que fazem sexo com homens (HSH). Grande parte das pesquisas direcionadas à infecção anal pelo HPV e sua relação com neoplasia intraepitelial-anal (NIA) e com o carcinoma esteve focada nos grupos de risco. Pouco interesse vem sendo destinado à investigação dos homens heterossexuais. Estudos epidemiológicos da prevalência da infecção pelo HPV em homens, mostraram que os heterossexuais masculinos apresentavam infecção anal pelo HPV em até 12%. As Sociedades médicas e os especialistas recomendam o rastreamento dos portadores de imunodepressão e dos HSH com citologia do raspado do canal anal. Entretanto, até o momento, não há recomendação de rastreamento para homens que fazem sexo com mulheres.

HIV- positive anal cancer: an update for the clinician

Anal cancer used to be a rare cancer traditionally associated with elderly women. There are approximately 5260 cases per year in the U.S. (1). The onslaught of the Human Immunodeficiency Virus (HIV) virus has led to a change in anal cancer demographics. Anal cancer is on the rise in the U.S and the number of anal cases documented has quadrupled in the past 20 yrs correlating with the rise of the HIV epidemic. The incidence of anal cancer is 40 to 80 fold higher in the HIV positive (HIV+) population when compared to the general population (2). With the advent of highly active antiretroviral therapy (HAART), HIV+ patients are living longer as less are progressing to AIDS. As a consequence non AIDS defining cancers such as anal cancer are on the rise. Factors implicated in the etiology of anal cancer in HIV+ patients include (Human papillomavirus) HPV virus status, sexual habits, and a history of smoking. HPV 16 and receptive anal intercourse (RAI) increase the risk of anal cancer by 33% over the general population. In the general population, the rate of anal cancer is approximately 0.9 cases per 100,000. In patients with a history of RAI, the rate approaches 35 cases per 100,000 which is equivalent to the prevalence of cervical cancer (3). Smokers are eight times more likely to develop anal cancer. There has been much discussion about tailoring treatment decisions in HIV+ patients with anal cancer. This review focuses on squamous cell carcinomas of the anal canal which comprise 80 to 90% of all anal cancers diagnosed and highlight key issues in the management of HIV+ anal cancer patients including recent clinical trials.