Systematic review of guidelines for the assessment and management of high-grade anal intraepithelial neoplasia (AIN II/III)

Comparing and contrasting clinical consensus and guidelines for anal intraepithelial neoplasia in different geographical regions

Anal Squamous Cell Carcinoma (ASCC) is an uncommon cancer with a recognised precursor Anal Intraepithelial Neoplasia (AIN). Although there are consistent evidence-based guidelines for the management of ASCC, historically this has not been the case for AIN and as a result there have been geographical variations in the recommendations for the treatment of AIN. More recently there have been updates in the literature to the recommendations for the management of AIN. To assess whether we are now closer to achieving an international consensus, we have completed a systematic scoping review of available guidelines for the screening, treatment and follow-up of AIN as a precursor to ASCC. MEDLINE and EMBASE were systematically searched for available clinical guidelines endorsed by a recognised clinical society that included recommendations on either the screening, treatment or follow-up of AIN. Nine clinical guidelines from three geographical areas were included. The most recent guidelines agreed that screening for AIN in high-risk patients and follow-up after treatment was necessary but there was less consensus on the modality of screening. Six Guidelines recommended the treatment of high-grade AIN and four guidelines describe a follow-up protocol of patients diagnosed with AIN. There appears to be increasing consensus on the treatment and follow-up of patients despite a poor evidence base. There is still significant discrepancy in guidance on the method to identify patients at risk of ASCC and AIN despite consensus between geographical regions on which patient subgroups are at the highest risk.

The importance of anal cancer screening and high-resolution anoscopy to gastroenterology practice

PURPOSE OF REVIEW

Although human papillomavirus (HPV)-related anal squamous cell cancer (ASCC) is rare, its incidence has been rising and in high-risk populations exceeds the incidence of cancers for which screening programs are implemented. Therefore, targeted screening techniques are being evaluated with high-resolution anoscopy (HRA) as the current gold standard because of its ability to detect anal intraepithelial dysplasia (AIN) and premalignant high-grade squamous intraepithelial lesions (HSILs). However, a scarcity of trained providers presents a barrier to screening.

RECENT FINDINGS

ASCC incidence is rising especially in elderly women and young black men. Premalignant HSIL may not only progress to ASCC but also regress. Biomarkers such as HPV type, p16 immunostaining and DNA methylation markers may emerge as predictors of disease progression.HRA with acetic acid and Lugol's iodine staining can be used to detect HSIL and ASCC. Recent studies suggest that anal cancer screening may have an impact on the stage of ASCC at diagnosis and the incidence of anal cancer.The Anal Cancer HSIL Outcomes Research (ANCHOR) study is underway to determine whether treating HSIL effects ASCC incidence.

SUMMARY

Although there are no consensus screening guidelines for anal cancer, it is reasonable to screen high-risk populations with physical examination, anal cytology and HRA. Gastroenterologists can support anal cancer screening programmes through identifying patients at risk, performing noninvasive screening and considering to incorporate endoscopic techniques to examine the anal canal. VIDEO ABSTRACT: http://links.lww.com/COG/A32.

Comparison between anal cytology, high-resolution anoscopy and HPV DNA genotyping by polymerase chain reaction in the post-treatment follow-up of condylomata acuminata

AIM

to evaluate the presence of subclinical HPV-induced anal lesions with anal cytology, High-Resolution Anoscopy (HRA) and HPV genotyping by polymerase chain reaction (PCR) in the follow-up of treated condylomata acuminata (CA).

METHODS

seventy-nine male patients were included. One month after anal CA eradication, the patients underwent brush samples collection for anal cytology and PCR, and HRA with biopsy of acetowhite lesions. These methods were compared within all patients and between groups, according to Human Immunodeficiency Virus (HIV) infection status: HIV-negative; HIV-positive with TCD4 count above and below 350 cells/mm3.

RESULTS

the most frequent HPV types were 6 and 16. HPV DNA was isolated in 92%. HIV infection was associated with a higher number of oncogenic HPV types (p=0.038). All patients with negative PCR had negative HRA and cytology. There were no differences in cytological, HRA or histopathological findings between groups.

CONCLUSION

the association of the findings of cytopathology, HRA and genotyping of HPV refined the diagnosis of HPV-induced lesions. The degree of immunodeficiency was not associated with increase in remnant HPV-induced anal lesions.

Acceptability of anal cancer screening tests for women living with HIV in the EVVA study

Background

Anal cancer is potentially preventable through screening. For screening to be implemented, the screening procedures must be acceptable to the affected population. The objective of the present study was to measure the acceptability of currently available anal cancer screening tests in a population of women living with hiv who had experienced the tests.

Methods

The evva study ("Evaluation of Human Immunodeficiency Virus, Human Papillomavirus, and Anal Intraepithelial Neoplasia in Women") is a prospective cohort study of adult women living with hiv in Montreal, Quebec. Participants were screened with cervical or anal hpv testing and cervical or anal cytology every 6 months for 2 years. High-resolution anoscopy (hra) and digital anal rectal examination (dare) were also performed systematically, with biopsies, at baseline and at 2 years. An acceptability questionnaire was administered at the final visit or at study withdrawal.

Results

Of 124 women who completed the acceptability questionnaire, most considered screening "an absolute necessity" in routine care for all women living with hiv [77%; 95% confidence interval (ci): 69% to 84%]. Yearly anal cytology or anal hpv testing was considered very acceptable by 81% (95% ci: 73% to 88%); hra every 2 years was considered very acceptable by 84% (95% ci: 77% to 90%); and yearly dare was considered very acceptable by 87% (95% ci: 79% to 92%). Acceptability increased to more than 95% with a longer proposed time interval. Pain was the main reason for lower acceptability.

Conclusions

Most participating women considered anal cancer screening necessary and very acceptable. Longer screening intervals and adequate pain management could further increase the acceptability of repeated screening.

Differences in the Immune Microenvironment of Anal Cancer Precursors by HIV Status and Association With Ablation Outcomes

Background

Anal high-grade squamous intraepithelial lesions (HSILs) are the precursors to anal cancer and frequently persist or recur following electrocautery ablation (EA). Impaired mucosal immunity may facilitate anal carcinogenesis. We characterized the immune microenvironment of anal HSILs in correlation with human immunodeficiency virus (HIV) serostatus and ablation outcomes.

Methods

Using immunohistochemistry, mucosa-infiltrating CD4+ and CD8+ lymphocytes were quantified in HSILs and benign mucosa from 70 HIV+ and 45 HIV- patients. Clinicopathological parameters were compared.

Results

Anal HSILs harbored more T lymphocytes than benign mucosa regardless of HIV status (P ≤ .03). Total T lymphocyte count and CD8+ subset were significantly higher in HIV+ HSILs versus HIV- HSILs (median cell count, 71 vs 47; 47 vs 22/high power field [HPF]; P < .001), whereas the CD4+ subset was comparable between groups (median, 24 vs. 25; P = .40). Post EA, HSILs persisted in 41% of HIV+ and 19% of HIV- patients (P = .04). Unadjusted analysis showed trends toward EA failures associated with HIV seropositivity (incidence rate ratio [IRR], 2.0; 95% CI, .8-4.9) and increased CD8+ cells (IRR, 2.3; 95% CI, .9-5.3).

Conclusions

Human immunodeficiency virus is associated with alterations of the immune microenvironment of anal HSILs manifested by increased local lymphocytic infiltrates, predominately CD8+. Human immunodeficiency virus seropositivity and excess mucosa-infiltrating CD8+ cells may be associated with ablation resistance.

Expectant management surveillance for patients at risk for invasive squamous cell carcinoma of the anus: a large US healthcare system experience

PURPOSE

To determine the impact of expectant management surveillance for patients at risk for squamous cell carcinoma of the anus (SCCA).

METHODS

Adult patients at risk for anal cancer, specifically those with human immunodeficiency virus (HIV) or known human papilloma virus (HPV) infections (anal dysplasia, anogenital warts, cervical dysplasia, or cervical cancer), underwent expectant management surveillance with targeted therapy of only grossly abnormal or symptomatic anoderm lesions. A retrospective analysis investigated the SCCA incidence in these surveilled populations and in the general population patients without known HIV or HPV infection.

RESULTS

There were 452 incident SCCA in a population of 5,978,510 patients (mean follow-up per patient of 5.4 years). Four hundred ten cancers (90.7%) developed in 5,750,501 HIV-negative patients without documented history of HPV infection (cumulative incidence 0.007%). In at-risk patient populations, the cumulative incidence was 0.69% in patients with anal dysplasia (6 out of 872 patients), 0.14% in HIV+ patients (8 out of 5626 patients), and less than 0.1% in the remaining at-risk groups: cervical cancer (1 out of 1168 patients), cervical dysplasia (14 out of 125,604 patients), and genital warts (14 out of 94,739 patients).

CONCLUSIONS

Expectant management surveillance, with targeted treatment for symptomatic or abnormal lesions, is an effective strategy for the diagnosis of anal cancer in at-risk patient populations. In this study, most patients who developed anal cancer had no known risk factors. A screening strategy for the general population needs to be further delineated.

Biomarker P16 predicts progression risk of anal low-grade squamous intraepithelial lesions

OBJECTIVES

The aim of this study was to determine whether biomarker P16 predicts progression risk for anal low-grade squamous intraepithelial lesions (LSILs).

DESIGN

A retrospective study.

METHODS

One hundred and nine HIV-infected and 18 HIV-uninfected patients with biopsy-proven anal LSIL at initial screening underwent surveillance high-resolution anoscopy and biopsy within 2 years of diagnosis. P16 immunohistochemistry was performed on index lesions and evaluated using a semi-quantitative scoring system. The association of predictors and lesional outcomes (progression, persistence or regression) was analysed using ordinal logistic regression models. A subset of p16-positive LSILs was tested for high-risk human papillomavirus (HR-HPV) DNA using real-time PCR.

RESULTS

Upon follow-up, 46 (36%) LSILs progressed to high-grade squamous intraepithelial lesion (HSIL), 50 (40%) persisted as LSIL and 31 (24%) regressed to benign mucosa (median 16 months, range 5-24 months). Age, sex, race, history of condylomata, CD4 T-cell count and HIV plasma viral load were similar regardless of clinical outcome. P16 immunoreactivity of index lesion was classified as block-positive (n = 36), focal-positive (n = 49) or negative (n = 42). Sixty-four percent of block-positive lesions progressed, as opposed to 35% of focal-positive and 14% of negative lesions (P < 0.001). HR-HPV DNA was detected in 90% of p16 block-positive lesions vs. 55% of focal-positive lesions. In unadjusted analyses, positive p16, HIV and former smoker status were significantly associated with lesional persistence and progression. P16 remained the only significant predictor in an adjusted model.

CONCLUSION

Biomarker p16 is the strongest predictor for anal LSIL-to-HSIL progression, outperforming other risk factors. To enhance the overall effectiveness of surveillance, we propose using p16 immunohistochemistry to help stratify patients at high vs. low risk of progression.

Clinical evaluation of anal intraepithelial neoplasia: are we missing the boat?

BACKGROUND

Anal intraepithelial neoplasia (AIN) is dysplasia in the epithelium of the anus and is a pre-malignant condition associated with a low rate of progression to invasive squamous cell carcinoma (SCC). The natural history of progression for AIN to anal SCC is poorly defined. This study aims to review our experience with AIN and investigate the natural history of progression.

METHODS

Data on all patients with AIN from January 2005 to December 2015 were retrospectively reviewed. Three separate databases were searched - Colorectal, Radiation Oncology and Infectious Diseases. All databases were cross-referred to obtain a complete but non-duplicated data set. Electronic charts were reviewed to obtain clinical information.

RESULTS

Twenty-eight patients were identified with AIN of various grades. There were 25 males, three females. Twenty of the male patients were human immunodeficiency virus (HIV) positive. Mean length of follow up was 56 months. Complete regression of AIN to normal was noted in 13 patients (46%). Four patients had persisting AIN III with no evidence of regression or malignant transformation. Nine patients with pre-existing AIN developed SCC (32%). Seven were positive for HIV infection (all males). Median time to progression was 36 months. None of the patients demonstrated clear linear pattern of progression of AIN to SCC.

CONCLUSION

High grade AIN may progress to anal SCC and surveillance is indicated. The exact natural history of progression for AIN is difficult to predict. There is no linear progression over time evident. HIV patients with AIN are at higher risk of developing SCC.

Factors associated with anal cancer screening follow-up by high-resolution anoscopy

OBJECTIVES

High-resolution anoscopy (HRA) is a potential screening method for detection of anal cancer precursors. We evaluated factors associated with adherence to recommended HRA follow-up time intervals among men who have sex with men (MSM).

METHODS

We employed a retrospective, observational cohort study with 155 MSM screened by HRA between 1 April 2011 and 31 March 2016 at a Federally Qualified Health Centre in Boston, Massachusetts.

RESULTS

The sample was 80% white, with a median age of 48 (non-normal distribution, IQR 15). All patients were assigned male sex at birth and none identified as transgender. Fifty patients (32%) followed up with a HRA appointment within 6 months of previous HRA detection of anal high-grade squamous intraepithelial lesion (HSIL). Among patients, 112 (72%) were HIV infected, 56 (36%) had a syphilis diagnosis during the study period, 89 (57.4%) had initiated Hepatitis A or B vaccination series, 70 (45.2%) accessed case management services and 19 (12.3%) utilised pre-exposure prophylaxis (PrEP). In bivariate analysis, patients who underwent recommended follow-up HRA within 6 months of HSIL diagnosis were less likely to report: case management utilisation (p=0.023), initiation of Hepatitis A or B vaccination (p=0.047), HIV diagnosis (p<0.001) and syphilis diagnosis (p=0.001), but were more likely to use HIV PrEP (p<0.001). In binomial logistic regression modelling after adjusting for age and race/ethnicity, patients who had follow-up with HRA within a recommended period of 6 months after HSIL diagnosis were less likely to have initiated Hepatitis A or B vaccination (adjusted OR 0.43, 95% CI 0.20 to 0.94), more likely to use PrEP (adjusted OR 4.47, 95% CI 1.30 to 15.49) and less likely to have a syphilis diagnosis (adjusted OR 0.34, 95% CI 0.14 to 0.86).

CONCLUSIONS

Three-quarters of patients with HSIL did not have follow-up HRA within the clinic's recommended follow-up period of 6 months following HSIL diagnosis by HRA. Future studies ought to explore whether addressing anal health during other STI-related care helps improve adherence to recommended time intervals for follow-up HRA. Given the high prevalence of STI and PrEP use, studies might also evaluate whether integrating HRA follow-up with other sexual health screenings helps improve adherence to recommended HRA follow-up.

Endoscopic submucosal dissection (ESD) for anal high-grade intraepithelial neoplasia: a case report

Anal intraepithelial neoplasia (AIN) is a precursor of anal carcinoma. Conventional therapy is based on topical and local ablative approaches. However, the recurrence rates are very high, leading to repetitive treatment sessions and need for long-term surveillance. Endoscopic submucosal dissection (ESD) is an established treatment for malignant early neoplasias of the gastrointestinal tract, especially in the esophagus, stomach, and colorectum. Japanese centers have reported few cases of ESD for early anal carcinoma. We report a case of high-grade AIN diagnosed with magnifying narrow-band imaging and chromoendoscopy that was resected R0 with ESD en bloc.

Cryotherapy for Intra- and Perianal High-Grade Squamous Intraepithelial Lesions in HIV-Positive Men who have Sex with Men

BACKGROUND

Available treatment options for anal high-grade squamous intraepithelial lesions (HSIL) in HIV-positive men who have sex with men (MSM) are limited by low response rates and frequent recurrences. Cryotherapy is an established therapeutic option for several pre-malignant skin disorders.

METHODS

This retrospective, non-randomized study included HIV-positive MSM who received intra- and/or perianal HSIL cryotherapy treatment between 30 December 2008 and 23 April 2015. Cryotherapy was applied in sessions 4-6 weeks apart for a maximum of five sessions. Patients received a follow-up high-resolution anoscopy (HRA) to assess treatment response. Complete and partial treatment responders were followed-up after 6 months and then every 6-12 months to investigate recurrent HSILs.

RESULTS

Of 64 patients [median age 48 years; interquartile range (IQR) 42-56] included in the study, six were lost to follow-up. In total, 35 (60%) of 58 patients responded to treatment. Of 64 patients, 31 (48%) reported one or more side effects, of which anal pain or tenderness and mild blood loss were reported most frequently. A total of 19 patients who responded to cryotherapy were adequately followed-up for over 18 months, of whom 13 (68%) had recurrent HSILs.

CONCLUSION

Cryotherapy is capable of clearing HSIL in HIV-positive MSM, and treatment success rates are comparable with those reported for current treatment modalities. The treatment is well tolerated, and side effects are relatively mild. Future studies should therefore compare the efficacy and tolerability of cryotherapy with those of current treatment modalities in randomized controlled trials.

Management of early anal cancer: need for guidelines and standardisation

PURPOSE

The optimal management of early squamous cell carcinoma of the anal canal (AC) is yet to be determined. This study investigated current practice in the management of early AC.

METHODS

A patterns of care survey was completed by Australian surgeons and radiation oncologists. Specific topics addressed were as follows: geographical location of practice, staging of disease, treatment approaches to T1N0 tumours and grade 3 anal intra-epithelial neoplasia (AIN3) lesions, radiotherapy planning, toxicities, follow-up and clinical trial involvement.

RESULTS

Sixty-four responses were obtained. For the management of T1N0 disease, half the respondents recommended standard dose chemo-radiotherapy (CRT) and one third recommended wide local excision (WLE). For the management of AIN3, half recommended WLE while a quarter advocated observation.

CONCLUSIONS

This study reveals a significant variation in the management of early AC. The development of guidelines specific to the treatment of early AC could standardise treatment while further research is required to define the optimal management of T1N0 AC and AIN.

Liver transplant recipients have a higher prevalence of anal squamous intraepithelial lesions

Background:

Anal squamous intraepithelial lesions (ASIL) are precancerous lesions of anal squamous cell carcinoma, with a higher prevalence in immunosuppressed patients. There are some studies in kidney transplant recipients, but there is no information regarding prevalence in liver transplantation. Our aim was to evaluate the prevalence of ASIL in this setting.

Methods:

Prospective case–control study involving liver transplant recipients without any other known risk factor for ASIL (n=59), which were compared with a healthy control group (n=57). All were submitted to anal cytology and high-resolution anoscopy was performed in those with abnormal results.

Results:

Ten (17%) of liver transplant recipients had abnormal cytological results, seven patients had atypical squamous cells of undetermined significance (ASC-US), one patient had atypical squamous cells that cannot exclude high-grade (ASC-H) and two patients had high-grade squamous intraepithelial lesions (HSIL). In the control group, one patient (2%) had an ASC-US result (P=0.005). Anal squamous intraepithelial lesions were confirmed in 7 out of 10 of liver transplant patients and 0 out of 1 in the controls (P=0.013) by high-resolution anoscopy with biopsies. Current smoking was the only risk factor for abnormal cytology (odds ratio=5.87, 95% confidence intervals=1.22–28.12, P=0.027).

Conclusions:

Liver transplant patients have a higher risk of ASIL. Screening should be considered, especially in smokers.

Condyloma Acuminatum, Anal Intraepithelial Neoplasia, and Anal Cancer in the Setting of HIV: Do We Really Understand the Risk?

BACKGROUND

The gold standard for surveillance of patients with anal lesions is unclear.

OBJECTIVE

The aim of this study was to stratify patients for risk of progression of disease and to determine appropriate intervals for surveillance of patients with anal disease.

DESIGN

This was a retrospective chart review for patients treated for anal lesions between 2007 and 2014. Only patients with ≥1 year of follow-up from index evaluation, pathology, documented physical examination, and anoscopy findings were included for analysis.

SETTINGS

The study was conducted at an urban university hospital.

PATIENTS

HIV-positive patients with anal lesions treated with excision and fulguration were included.

MAIN OUTCOME MEASURES

Recurrence of anal lesions, progression of disease, and progression to cancer were measured.

RESULTS

Ninety-one patients met inclusion criteria. The mean age was 41.6 years, and mean follow-up was 38.6 months (range, 11.0-106.0 mo). On initial pathology, 8 patients (8.8%) had a diagnosis of condyloma acuminatum without dysplasia, 20 patients (22%) had anal intraepithelial neoplasia I, 32 (35.2%) had anal intraepithelial neoplasia II, and 31 (34.1%) had anal intraepithelial neoplasia III. Sixty-nine patients (75.8%) had repeat procedures. Seven (87.5%) of 8 patients with condyloma and 6 (30%) of 20 patients with anal intraepithelial neoplasia I progressed to high-grade lesions. Five (15.6%) of 32 patients progressed from anal intraepithelial neoplasia II to III, and 2 patients with anal intraepithelial neoplasia III (6.5%) developed squamous cell carcinoma (2.3% for the entire cohort).

LIMITATIONS

This was a single institution study. High-resolution anoscopy was not used.

CONCLUSIONS

All of the HIV-positive patients with condyloma or anal intraepithelial neoplasia, regardless of the presence of dysplasia, should be surveyed at equivalent 3-month time intervals, because their risk of progression of disease is high. Video Abstract at http://links.lww.com/DCR/A389.

Argon plasma coagulation treatment of anal high-grade squamous intraepithelial lesions in men who have sex with men living with HIV: results of a 2-year prospective pilot study

OBJECTIVES

Men who have sex with men (MSM) living with HIV are at high risk for anal high-grade squamous intraepithelial lesions (HSILs) and cancer. The best management of anal HSIL remains unclear. Our objective was to assess whether argon plasma coagulation (APC) could be safe, well tolerated and efficient to treat anal HSILs in MSM living with HIV.

METHODS

A prospective phase II, open-label, pilot study was conducted to evaluate APC to treat anal HSILs in 20 HIV-positive MSM. Participants were followed for 2 years after their first treatment.

RESULTS

Twenty men with persistent HSILs completed the 2-year study. Their baseline median CD4 count was 490 cells/μL and 85% had undetectable HIV viral loads. Overall, 65% (13/20) of participants were clear of HSILs at their 24-month visit. The initial response rates after the first, second and third APC treatments were 45%, 44% and 67%, respectively, but recurrences were common. The main side effect was pain during and within 1 week after the treatments. There were no long-term side effects, nor serious adverse events related to the procedure. Cost is a drawback.

CONCLUSIONS

APC can be used to treat anal HSILs in HIV-seropositive MSM, and requires repeated treatment because of a high recurrence rate. As successful treatment of human papillomavirus (HPV) infection or eradication of the anal transitional zone remains impossible, HSIL treatment is challenging and requires long-term follow-up.

Anal Neoplasia in Inflammatory Bowel Disease: Classification Proposal, Epidemiology, Carcinogenesis, and Risk Management Perspectives

Patients with inflammatory bowel disease [IBD] may develop, similarly to individuals from general population, rare cases of human papilloma virus [HPV]-related anal canal squamous cell carcinoma [SCC] and intra-epithelial precursor lesions, as well as very rare cases of anal canal adenocarcinoma. Patients with chronic perianal Crohn's disease [CD] are at substantial risk of developing SCC or adenocarcinoma from the fistula-lining epithelium, as well as SCC or adenocarcinoma arising from chronic anorectal ulcerations or strictures. Based on this lesion stratification, we provide in this review tailored incidence estimates and we propose an IBD-specific classification of all types of anal neoplasia that may occur in patients with IBD. After reviewing putative carcinogenesis of all types of neoplasia, we conclude that HPV vaccination could reduce the incidence of HPV-related lesions, although an anal screening programme related to these lesions is not mandatory on the sole basis of IBD. By contrast, we point out that all patients with chronic perianal CD should be explored in depth, including biopsies under anaesthesia and fistula curettage when necessary, in case of any change in anal symptoms ─in particular new, increasing, unexplained pain. Finally, we conclude that there is an urgent need for elaborating and evaluating surveillance algorithms in patients with chronic perianal CD, in order to avoid cancers with late diagnosis and poor prognosis.

Screening for Squamous Cell Anal Cancer in HIV Positive Patients: A Five-Year Experience

AIM

Potential screening modalities for early diagnosis of squamous cell anal cancer (SCC) in HIV patients include digital anorectal examination (DARE), anal Papanicolaou testing (Pap test), human papilloma virus (HPV) co-testing, and high-resolution anoscopy. The aim of this study was to demonstrate the results of a five-year screening program for SCC in HIV patients.

MATERIALS AND METHODS

We conducted a retrospective study on 204 HIV patients who underwent a screening program for SCC from October 2010 to January 2015. All patients were screened by DARE, anal Pap test, including HPV test and cytology, and high-resolution video-proctoscopy (HR-VPS) with and without acetic acid 3%. Depending on macroscopic appearance and biopsies, patients underwent observation or treatment. Median follow-up was 36 months.

RESULTS

Cytologic abnormalities (Cyt+) for high-risk HPV genotypes were recorded in 34% of patients. HR-VPS was positive in 59 patients (29%), of whom 13 patients (22%) were positive for warts; the rest have typical features of anal intraepithelial neoplasia (AIN). Sixteen (8%) patients had AIN (AIN I-III) and underwent wide local excision, ablation, or imiquimod. Absence of progression was recorded. Fourteen patients (7%) had SCC: eight (57%) with no evidence of recurrence, two (14%) had recurrence, and four (29%) died from metastatic disease.

CONCLUSIONS

Our data demonstrated a successful screening program in preventing SCC in HIV patients. We demonstrate the advantages of progression towards SCC. Moreover, we used a new screening tool, the HR-VPS, a low-cost and manageable instrument to collect patients' long-term data.

Human papillomavirus and gastrointestinal cancer: A review

Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. Exposure to HPV is very common, and an estimated 65%-100% of sexually active adults are exposed to HPV in their lifetime. The majority of HPV infections are asymptomatic, but there is a 10% chance that individuals will develop a persistent infection and have an increased risk of developing a carcinoma. The International Agency for Research on Cancer has found that the following cancer sites have a strong causal relationship with HPV: cervix uteri, penis, vulva, vagina, anus and oropharynx, including the base of the tongue and the tonsils. However, studies of the aetiological role of HPV in colorectal and esophageal malignancies have conflicting results. The aim of this review was to organize recent evidence and issues about the association between HPV infection and gastrointestinal tumours with a focus on esophageal, colorectal and anal cancers. The ultimate goal was to highlight possible implications for prognosis and prevention.