Comparison of 2 anal cytology protocols to predict high-grade anal intraepithelial neoplasia

Self-collected versus clinician-collected anal swabs for anal cancer screening: A systematic review and meta-analysis

Anal squamous cell carcinoma (ASCC) incidence is increasing globally. International consensus guidelines published in 2024 include HPV and/or cytology testing of anal swabs in those at greatest risk of ASCC. Self-collected anal swabs may be important for increasing screening uptake, but evidence is needed as to their equivalence to clinician-collected swabs. We searched Medline, Embase, Cochrane Library, and CINAHL databases for publications to 13 June 2023. Studies were included if reporting data on HPV testing, cytology testing, or acceptability, for both self- and clinician-collected anal swabs. Risk of bias was assessed using the QUADAS-2 assessment tool. The primary outcome was HPV and cytology sampling adequacy. Secondary outcomes were HPV and cytology results, and acceptability of collection methods. Thirteen papers describing 10 studies were eligible. Sample adequacy was comparable between self- and clinician-collected swabs for HPV testing (meta-adequacy ratio: 1.01 [95% CI 0.97-1.05]) but slightly lower for cytology by self-collection (meta-adequacy ratio: 0.91 [95% CI 0.88-0.95]). There was no significant difference in prevalence (meta-prevalence ratio: 0.83 (95% CI 0.65-1.07) for any HR-HPV, 0.98 (95% CI 0.84-1.14) for any HPV, and 0.68 (95% CI 0.33-1.37) for HPV16), or any cytological abnormality (meta-prevalence ratio 1.01 [95% CI 0.86-1.18]). Only three papers reported acceptability results. Findings indicate self-collection gives equivalent sample adequacy for HPV testing and ~ 10% inferior adequacy for cytological testing. Meta-prevalence was similar for HPV and cytology, but confidence intervals were wide. Larger studies are required to definitively assess use of self-collected swabs in anal cancer screening programs, including acceptability.

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.

Establishing the accuracy of a new and cheaper sample collection tool: Oral cytology versus oral histopathology

Objective:

High cost of tools used for the collection of oral cytology sample; deters their use as mass screening tool in the developing countries. Hence, this study aims to assess the diagnostic accuracy of a new, cheaper sample collection tool in the field of oral exfoliative cytology through comparison with histopathology.

Materials and Methods:

Fifty-seven patients out of 394 cases were selected for the study in whom the cytological examination was performed using the wooden end of a sterile cotton swab followed by biopsy. The cytological smear classified in accordance with the Pap classification was compared with the histopathological diagnosis.

Results:

The study recruited 11 cases of oral potentially malignant disorders, 33 cases of oral carcinomas, and 13 cases of other lesions. The sensitivity and specificity of the cytology test using the wooden end of a sterile cotton swab was 75.0% and 61.5%, respectively. The Spearman's correlation coefficient was 0.618, with the P < 0.01.

Conclusion:

Our study proves that the use of wooden end of a sterile cotton swab stick offers a low cost and fairly effective solution which is not only easily available but can be potentially applied as a mass screening tool at primary health-care centers.

Cytology in Anal Cancer Screening: Practical Review for Clinicians

The incidence and mortality of anal squamous cell carcinoma (SCC) are expected to continue to increase in the next 20 years. High-risk groups for anal SCC, i.e., human immunodeficiency virus (HIV)-positive patients, men who have sex with men (MSM), women with previous genital neoplasia, and solid-organ transplant recipients, have been identified. HIV-positive MSM have the highest risk, and some societies have advocated for anal cancer screening to be done in this population. Screening for anal SCC follows the same principles as that for cervical cancer since there are similarities between the two types of cancers. Anal cytology has been recommended as an initial screening method for high-risk groups, e.g., HIV-positive MSM. Normally, the cytology is liquid based and collected blindly by a clinician using a Dacron swab and it is especially used for internal lesions detection. The sensitivity to predict anal high-grade squamous intraepithelial lesions is higher in immunosuppressed patients with a high burden of the disease. The report should include the classification, normally according to the Bethesda terminology and the sample adequacy, in a manner similar to that for cervical cytology. In cases involving unsatisfactory samples, it is important to repeat the procedure given the prevalence of anal squamous cytological abnormalities in follow-up cytology procedures. The absence of transformation zone cells in anal cytology seems to increase the risk of false-negative results.

Practice parameters for the diagnosis and treatment of anal intraepithelial neoplasia (AIN) on behalf of the Italian Society of Colorectal Surgery (SICCR)

Squamous cell carcinoma (SCC) of the anus is a human papilloma virus (HPV) related malignancy that is preceded by anal intraepithelial neoplasia (AIN) making this cancer, at least theoretically, a preventable disease. In the past 10 years the diagnosis, management and nomenclature of AIN has dramatically changed. Increased life expectancy in human immunodeficiency virus (HIV) positive patients due to highly active antiretroviral therapy (HAART) has caused an increase in the incidence of SCC of the anus. While many experts recommend screening and treatment of anal high-grade squamous intraepithelial lesion (HSIL), there is no consensus on the optimal management these lesions. Therefore, there is a need to review the current evidence on diagnosis and treatment of AIN and formulate recommendations to guide management. Surgeons who are members of the Italian Society of Colorectal Surgery (SICCR) with a recognized interest in AIN were invited to contribute on various topics after a comprehensive literature search. Levels of evidence were classified using the Oxford Centre for Evidence-based Medicine of 2009 and the strength of recommendation was graded according to the United States (US) preventive services task force. These recommendations are among the few entirely dedicated only to the precursors of SCC of the anus and provide an evidence-based summary of the current knowledge about the management of AIN that will serve as a reference for clinicians involved in the treatment of patients at risk for anal cancer.

Comparison of nylon-flocked swab and Dacron swab cytology for anal HSIL detection in transgender women and gay, bisexual, and other men who have sex with men

BACKGROUND

An anal histological high-grade squamous intraepithelial lesion (hHSIL) is an anal cancer precursor. Experts recommend Dacron swab anal cytology as a primary screen for anal hHSILs, especially among human immunodeficiency virus-infected and -uninfected men who have sex with men (MSM). Studies have shown that Dacron cytology inaccurately predicts anal hHSILs and results in unnecessary diagnostic procedures. Nylon-flocked (NF) swabs have been shown to trap pathogens and cells well. Thus, this study compared test characteristics of anal cytology using NF and Dacron swab collection protocols to predict anal hHSILs.

METHODS

A single-visit, randomized clinical trial compared NF and Dacron swab anal cytology specimens to predict high-resolution anoscopy and biopsy-diagnosed anal hHSILs. Data for 326 gay men, bisexual men, other MSM, and male-to-female transgender women contributed descriptive and tabular statistics with which unadjusted and fully adjusted logistic regression models were constructed. The models estimated the odds of hHSILs, test accuracy (area under the curve [AUC]) and sensitivity, and specificity as well as the positive and negative predictive values of abnormal NF and Dacron cytology for predicting hHSILs.

RESULTS

In the fully adjusted model, the sensitivities for NF and Dacron cytology were nearly equal (48% vs 47%), but the specificity was higher with NF cytology (76% vs 69%). Comparisons of the areas under receiver operating characteristic curves showed that NF cytology alone predicted hHSILs better than the covariate model (AUC, 0.69 vs 0.63; P = .02), but NF and Dacron cytology comparisons showed no statistically significant differences (AUC, 0.69 vs 0.67; P = .3).

CONCLUSIONS

NF cytology and Dacron cytology provide modest sensitivity, but NF cytology has higher specificity and accuracy, and this is important for lowering the costs of population-based screening.

An overview of anal intraepithelial neoplasia

Anal intraepithelial neoplasia (AIN) and anal squamous cell carcinoma (ASCC) are on the rise in the United States, especially among men who have sex with men, HIV-positive or other immunocompromised patients, and women with a history of cervical, vaginal, or vulvar cancer. Strong evidence supports the human papillomavirus as the causative factor in anal dysplasia; reducing the risk of HPV infection can reduce rates of ASCC. High-risk patients should be screened for AIN, but no universal screening guidelines exist, and more studies are needed to develop a national protocol for screening and management of patients with AIN.

Pathobiology of human papillomaviruses in human immunodeficiency virus - Infected persons

There is a complex interrelationship between human papillomaviruses (HPV) and human immunodeficiency viruses (HIV) that has been recognized from the start of the HIV epidemic. Cervical cancer was used as a surveillance indicator for acquired immunodeficiency syndrome (AIDS) before definitive identification of the viral etiology of either condition were known. Careful epidemiologic studies combined with clinical and laboratory measures of HPV, HPV-associated disease, and HIV have helped us understand many aspects of the relationship between these two virus groups; however, questions remain. The histopathology associated with HPV is identical in HIV-positive and negative patients though the lesions are more frequent, with higher frequency of multiple HPV types, and persistent in HIV infected individuals. In this review we will briefly explain the pathobiology of HPV in HIV-infected persons and the potential impact of secondary (screening) and primary (vaccination) prevention to reduce HPV-associated disease in those infected with HIV.

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

INTRODUCTION

Human papillomavirus (HPV) and anal carcinoma are prevalent in high-risk patients including human immunodeficiency virus (HIV)-positive patients. There are currently no clear guidelines for screening, however. We assessed anal cytology specimens and HPV testing at an inner-city hospital by correlating anal cytology with anal biopsy (bx), and evaluated if results differed with traditional proctoscopy (TP) or high-resolution anoscopy (HRA).

MATERIALS AND METHODS

209 anal cytology and subsequent biopsies taken during the period 2003-2014 from 152 male patients were reviewed. Demographic data for age, sex, HIV, HPV, cytology, histology, and the method of biopsy were analyzed.

RESULTS

All specimens were followed by a biopsy within a period of 6 months. Ninety-seven percent of patients were HIV-positive and 43% had AIDS. Lesions most diagnosed on cytology were low-grade squamous intraepithelial lesion (LSIL) (52%) and atypical squamous cells of undetermined significance (ASC-US) (21.5%). Lesions most diagnosed on bx were anal intraepithelial neoplasia (AIN) grade 2-3 (52%) and AIN grade 1 (37%). Almost all ASC-US cases tested for HPV were positive (97%). There was cytology histology correlation in 48% of LSIL and 83% of high-grade squamous intraepithelial lesions. Anal cytology had 97% sensitivity in detecting AIN and carcinoma and a positive predictive value of 96%. There was no difference in rate of detection of AIN 1and AIN 2-3 on bx using TP versus HRA.

CONCLUSION

Screening in high-risk patients detected almost all high- and low-grade squamous intraepithelial lesions, however, anal cytology alone could not predict the degree of dysplasia. It may be prudent to perform anal bx in all atypical anal cytology. Clear guidelines are needed for screening of a high risk population.

Self-collection tools for routine cervical cancer screening: a review

Sub-optimal participation is a major problem with cervical cancer screening in developing countries which have no organized national screening program. There are various notable factors such as 'embarrassment', 'discomfort' and 'no time' cited by women as they are often also the bread winners for the family. Implementation of self-sampling methods may increase their participation. The aim of this article was to provide a survey of various types of self-sampling tools which are commonly used in collection of cervical cells. We reviewed currently available self-sampling devices and collated the advantages and disadvantages of each in terms of its acceptance and its accuracy in giving desired results. In general, regardless of which device is used, self-sampling for cervical scrapings is highly acceptable to women in most of the studies cited.

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.

Some are more equal--a comparative study on swab uptake and release of bacterial suspensions

Objectives

Swabs are widely used to collect samples for microbiological analyses from various clinical settings. They vary by material, size, and structure of the tip. This study investigates the uptake and release capacities for liquid and bacteria.

Methods

Five swabs were analyzed for their uptake and release capacities of Staphylococcus aureus and Staphylococcus epidermidis suspensions. Two approaches were investigated providing volume-restricted and unrestricted amounts of bacterial suspensions to mimic various clinical situations. Volume and bacterial uptake and release were measured in milligrams and by counting colony forming units (CFU), respectively.

Results

Volume uptake and release in the unrestricted setting varied highly significant between 239.6 mg and 88.7 mg (p<0.001) and between 65.2 mg and 2.2 mg (p<0.001), respectively. In the volume-restricted setting the complete volume was absorbed by all swabs, volume release could only be detected for flocked swabs (2.7 mg; p<0.001). Highest amount of CFU release was detected for the MWE Dryswab in the unrestricted setting for both S. aureus and S. epidermidis with 1544 CFU and 553 CFU, respectively, lowest release for the Sarstedt neutral swab with 32 CFU and 17 CFU, respectively (p<0.001). In the volume-restricted setting MWE Σ-Swab released the highest bacterial amount with 135 CFU S. aureus and 55 CFU S. epidermidis, respectively, the lowest amount was released by Mast Mastaswab with 2 CFU S. aureus and 1 CFU S. epidermidis, respectively (p<0.001). Within the range of the utilized bacterial concentrations, uptake/release ratios were identical for the particular swab types and independent of the bacterial species.

Conclusions

The influence of the swab type on subsequent diagnostic results is often underestimated. Uptake and release of the investigated bacteria vary significantly between different swab types and sampling conditions. For best diagnostic outcome swabs should be chosen according to the examined situation and the swab performance profile.