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

Anal dysplasia and anal cancer screening practices among liver transplant centers in the United States: Results of an online survey

BACKGROUND

Solid organ transplant recipients are at an increased risk for anogenital Human Papillomavirus (HPV)-related disease, including anal high-grade squamous intraepithelial lesions (HSIL) and anal squamous cell cancer (ASCC). Guidelines for ASCC screening in transplant recipients are limited. Our aim was to understand current practice of ASCC screening in adult liver transplant (LT) candidates and recipients at transplant centers across the United States.

METHODS

We surveyed medical directors of 113 LT centers across the United States which had publicly available contact information. The survey evaluated center perceptions on cancer and HPV disease risk in transplant populations, ASCC screening, barriers and facilitators for ASCC screening and HPV vaccination practices.

RESULTS

We received 26/113 (23%) responses, of which 24 were complete and included in the analysis. Eleven of 24 (46%) centers reported screening for ASCC and 3/24 (12.5%) centers reported having formal guidelines. Centers who perform ASCC screening were more likely to perform transplants in people living with HIV and were more aware of the burden of HPV disease in transplant populations. All respondents believed that additional data on the impact of screening on ASCC incidence would support screening decisions. Increased access to specialists for screening/high-resolution anoscopy was also perceived as a facilitator. Only 7/24 (29%) centers regularly evaluated HPV vaccination status of their patients.

CONCLUSION

This national survey of LT centers reveals non-standardized ASCC screening practices, and identified data, educational and resource needs to improve prevention of ASCC in this population.

Anal Cancer: Emerging Standards in a Rare Rare Disease

The social stigma surrounding an anal cancer diagnosis has traditionally prevented open discussions about this disease. However, as recent treatment options and an increasing rate of diagnoses are made worldwide, awareness is growing. In the United States alone, 9,090 individuals were expected to be diagnosed with anal cancer in 2021. The US annual incidence of squamous cell carcinoma of the anus continues to increase by 2.7% yearly, whereas the mortality rate increases by 3.1%. The main risk factor for anal cancer is a human papillomavirus infection; those with chronic immunosuppression are also at risk. Patients with HIV are 19 times more likely to develop anal cancer compared with the general population. In this review, we have provided an overview of the carcinoma of the anal canal, the role of screening, advancements in radiation therapy, and current trials investigating acute and chronic treatment-related toxicities. This article is a comprehensive approach to presenting the existing data in an effort to encourage continuous international interest in anal cancer.

Carcinogenesis and Cancer Progression in De Novo Anal Squamous Cell Carcinoma After Organ Transplantation: A Systematic Review

Our aim was to perform a comprehensive literature review on the pathogenesis of squamous anal cancerin patients after solid-organ transplant. Medical databases were consulted until June 1, 2020, for potentially relevant publications.All studies on pathogenesis of de novo anal squamous cell carcinoma in solid-organ transplant recipients were included. Two researchers independently performed study selection, quality assessment, and data extraction and analysis. Twenty-one studies were included.None ofthe selected papers had been solely focused on carcinogenesis. Most ofthe studies identified human papillomavirus infection and immunosuppression to be significantly correlated with the development of de novo anal cancer in adult solid organ transplant recipients. CD4+ T-cell depletion and inactivation oftumor suppressor pathways were mainly implicated. All solid-organ transplant recipients, especially those who were human papillomavirus positive, were shown to be at increased risk for the development of posttransplant anal cancer. Further studies are needed to determine the specific mechanisms of pathogenesis according to different solid-organ transplant populations.

Multizonal anogenital neoplasia in women: a cohort analysis

BACKGROUND

There is currently a lack of information on full anogenital evaluation of women with a previous history of anogenital neoplasia.

METHODS

Retrospective analysis of the Homerton Anogenital Neoplasia Service records from January 2012 to March 2017, to identify all new referrals of women with previous anogenital neoplasia, who had had at least one complete examination of all anogenital sites. Multizonal anogenital disease (MZD) was defined as the presence of high-grade squamous intraepithelial lesions (HSIL)/carcinoma concurrently at two or more of the following sites/zones: perianus, anal canal, vulva, vagina or cervix.

RESULTS

253 women were included, mean age was 47 (SD=15) years and median duration of follow-up was 12 (IQR=21) months. Fifty-six women (22%) were diagnosed with MZD at first assessment and/or during follow-up. Current smokers (RR=1.84, 95% CI 1.21-2.79, p=0.004) and women on immunodulators/immunosuppressive drugs (RR=2.57, 95% CI 1.72-3.86, p<0.001) had an increased risk for MZD. The risk was lower for women without a previous history of anogenital high-grade lesions/cancer compared to those with this history (RR=0.06, 95% CI 0.01-0.45, p=0.006).

CONCLUSIONS

Multizonal assessment was important to diagnose occult areas of disease and should be especially considered in current smokers, pharmacologically immunocompromised and those with a previous history of anogenital HSIL/cancer.

Burden of anal squamous cell carcinoma, squamous intraepithelial lesions and HPV16 infection in solid organ transplant recipients: A systematic review and meta-analysis

The number of solid organ transplant recipients (SOTR), and their life expectancy, is increasing, with higher risk for long-term complications from immunosuppression. We carried out a systematic review describing the burden of anal squamous cell carcinoma (SCC), and its surrogates, in SOTR. We conducted mixed effect model-based meta-analyses evaluating incidence of anal SCC (standardized incidence ratio [SIR] vs general population, and absolute incidence rate [IR]), prevalence of anal squamous abnormalities, and human papillomavirus (HPV) 16. Generalized I2 statistics were calculated, quantifying heterogeneity. Anal SCC incidence in SOTR was elevated vs the general population (pooled SIR = 6.8, 95% confidence interval [CI], 4.3-10.9; 6 studies including 241 106 SOTR; I2  = 82.3%), with an absolute IR of 12.3 (95% CI, 10.4-14.7) per 100 000 person-years (5 studies including 1 079 489 person-years; I2  = 0%). Prevalence of abnormal anal cytology was 12.9% (95% CI, 9.2%-17.7%; 6 studies including 328 SOTR; I2  = 17.4%). For histology, the pooled prevalence estimate of anal squamous intraepithelial lesions was 22.4% (95% CI, 17.3%-28.5%; 3 studies including 214 SOTR; I2  = 0%), with 4.7% (95% CI, 2.5%-8.5%; I2  = 0%) high-grade squamous intraepithelial lesions. Pooled anal HPV16 prevalence was 3.6% (95% CI, 1.6%-7.8%; 4 studies including 254 SOTR; I2  = 17.6%). There was substantial and consistent evidence of elevated anal SCC incidence in SOTR.

New Insights into the Role of Human Papillomavirus in Anal Cancer and Anal Wart Development

Human papillomavirus is associated with several anogenital and oropharyngeal lesions, including warts, premalignant lesions, and cancer. There are specific groups that were identified as high-risk groups for anal squamous cell carcinoma and anal human papillomavirus infection, namely HIV-positive patients, men who have sex with men, women with genital tract neoplasia, and solid organ transplant recipients. Condylomas have classically been considered to be a benign lesion, with an exception made for the Buschke-Loewenstein tumor, but several publications have shown that a high percentage of condylomas harbor high-grade lesions. Due to the similarities between anal and cervical carcinogenesis, anal cancer screening based on anal cytology and referral to high-resolution anoscopy, in case of abnormalities, have been advocated. Testing for anal human papillomavirus is not routinely done in anal cancer screening, because of the very high prevalence in high-risk populations. The large majority of anal cancers are squamous cell carcinomas (SCC), and around 90% are attributed to human papillomavirus. Human papillomavirus positivity in anal SCC seems to have a prognostic value, with better survival in those patients with positive tumors. Prophylactic vaccination has been shown to be important for prevention of anal human papillomavirus-related lesions.

Expression of microRNAs 16, 20a, 150 and 155 in anal squamous intraepithelial lesions from high-risk groups

Anal squamous intraepithelial lesions (ASIL) or anal intraepithelial neoplasia (AIN) are precancerous lesions. microRNAs (miRNAs) have been implicated in cervical carcinogenesis, but have never been assessed in anal precancerous lesions. Our aim was to evaluate the expression of miR-16, miR-20a, miR-150 and miR-155 in several grades of ASIL obtained from high-risk patients, submitted to anal cancer screening from July 2016 to January 2017. Lesions were classified according to the Lower Anogenital Squamous Terminology (LAST) in low-grade (LSIL) and high-grade squamous intraepithelial lesions (HSIL), and the AIN classification in AIN1, AIN2 and AIN3. A hundred and five biopsies were obtained from 60 patients. Ten samples were negative (9.5%), 63 were LSIL (60%) and 32 were HSIL (30.5%) according to the LAST. Twenty seven (26%) were negative for dysplasia, 46 were classified as AIN1 (44%), 14 as AIN2 (13%) and 18 as AIN3 (17%) according to the AIN classification. There was no statistically significant difference in the fold expression of miR-16, miR-20a, miR-150 and miR-155, according to either classification. Although non- significant, there was an increasing trend in the miR-155 fold expression from negative samples to HSIL, with the highest fold expression increase in both LSIL and HSIL compared to the other miRNAs.

Anal High-Grade Squamous Intraepithelial Lesions in Pharmacologically Immunocompromised Patients Followed in a Referral Center

BACKGROUND

Information is lacking regarding anal/perianal precancerous lesions in referral cohorts of pharmacologically immunocompromised patients.

OBJECTIVE

The aim of this study is to evaluate the prevalence of anal/perianal high-grade squamous intraepithelial lesions in a referral cohort of patients on immunomodulator/immunosuppressive medications, who were assessed and followed with high-resolution anoscopy.

DESIGN

This is a retrospective study.

SETTING

This study was conducted in a single anal neoplasia service from January 2012 to June 2017.

PATIENTS

Patients on chronic immunomodulator/immunosuppressive medications were included. Cases of concomitant immunosuppression due to HIV infection were excluded, and immunosuppression due to chemotherapy was not considered for this analysis.

INTERVENTION

High-resolution anoscopy was performed.

MAIN OUTCOME

The primary outcome measured was the prevalence of anal/perianal high-grade squamous intraepithelial lesions in a referral cohort of pharmacologically immunocompromised patients.

RESULTS

Fifty-four patients were included, of whom 40 were women (74%), with a mean age of 48 ± 17 years. A total of 232 high-resolution anoscopy examinations were performed in this cohort. At the first evaluation, 28 patients (52%) were diagnosed with anal and/or perianal high-grade squamous intraepithelial lesions (including 2 cases of perianal squamous cell carcinoma); 11 cases (20%) were new diagnoses. Ten of 46 patients (22%) with follow-up developed a new lesion (high-grade/cancer) during a median follow-up period of 17 (interquartile range, 6-28) months. Overall, 37 patients (69%) in our cohort had anal/perianal high-grade squamous intraepithelial lesions ever diagnosed (including previous history, first visit, and follow-up); 5 patients had perianal squamous cell carcinoma. At our center, 6% of the new referrals were known to be pharmacologically immunocompromised patients.

LIMITATIONS

The retrospective nature of this study, the heterogeneity of the cohort, and the absence of human papillomavirus testing were limitations of this study.

CONCLUSIONS

The presence of anal and/or perianal high-grade squamous intraepithelial lesions or cancer detected by high-resolution anoscopy in this referral population was high, and the detection of new lesions suggests that long-term follow-up is needed. Patients on immunomodulator/immunosuppressive drugs represented only a small percentage of the new referrals to our center. See Video Abstract at http://links.lww.com/DCR/A748.