Treatment of Anal High-Grade Squamous Intraepithelial Lesions to Prevent Anal Cancer

The invasive potential of cervical intraepithelial neoplasia 3 (CIN3; also termed stage 0 carcinoma) has been poorly defined. At the National Women's Hospital, Auckland, New Zealand, treatment of CIN3 was withheld from a substantial number of women between 1965 and 1974 as part of an unethical clinical study. The resulting variation in management allows comparison of the long-term risk of invasive cancer of the cervix in women whose lesion was minimally disturbed with those who had adequate initial treatment followed by conventional management. We aimed to estimate the long-term risk of invasive cancer in these two groups of women. A judicial inquiry referred for independent clinical review in 1988 all women for whom there remained doubt about the adequacy of their management. Between February, 2001, and December, 2004, medical records, cytology, and histopathology were reviewed for all women with CIN3 diagnosed between 1955 and 1976, whose treatment was reviewed by judicial inquiry and whose medical records could be located, and linkages were done with cancer and death registers and electoral rolls. To take into account the probability that the CIN3 lesion had been completely removed, we classified adequacy of treatment by type of procedure, presence of CIN3 at the excision margin, and subsequent cytology. The primary outcome was cumulative incidence of invasive cancer of the cervix or vaginal vault. Follow-up continued until death or Dec 31, 2000, whichever came first. Analyses accounted for procedures during follow-up. 1229 women whose treatment was reviewed by the judicial inquiry in 1987-88 were included. Of these, 48 records (4%) could not be located and 47 women (4%) did not meet the inclusion criteria. At histopathological review, a further 71 (6% of 1134) women were excluded because the review diagnosis was not CIN3. We identified outcomes in the remaining 1063 (86% of 1229) women diagnosed with CIN3 at the hospital in 1955-76. In 143 women managed only by punch or wedge biopsy, cumulative incidence of invasive cancer of the cervix or vaginal vault was 31.3% (95% CI 22.7-42.3) at 30 years, and 50.3% (37.3-64.9) in the subset of 92 such women who had persistent disease within 24 months. However, cancer risk at 30 years was only 0.7% (0.3-1.9) in 593 women whose initial treatment was deemed adequate or probably adequate, and whose treatment for recurrent disease was conventional. This study provides the most valid direct estimates yet available of the rate of progression from CIN3 to invasive cancer. Women with untreated CIN3 are at high risk of cervical cancer, whereas the risk is very low in women treated conventionally throughout.

The terminology for human papillomavirus (HPV)-associated squamous lesions of the lower anogenital tract has a long history marked by disparate diagnostic terms derived from multiple specialties. It often does not reflect current knowledge of HPV biology and pathogenesis. A consensus process was convened to recommend terminology unified across lower anogenital sites. The goal was to create a histopathologic nomenclature system that reflects current knowledge of HPV biology, optimally uses available biomarkers, and facilitates clear communication across different medical specialties. The Lower Anogenital Squamous Terminology (LAST) project was co-sponsored by the College of American Pathologists (CAP) and the American Society for Colposcopy and Cervical Pathology (ASCCP) and included 5 working groups; three work groups performed comprehensive literature reviews and developed draft recommendations. Another work group provided the historical background and the fifth will continue to foster implementation of the LAST recommendations. After an open comment period, the draft recommendations were presented at a consensus conference attended by LAST work group members, advisors and representatives from 35 stakeholder organizations including professional societies and government agencies. Recommendations were finalized and voted upon at the consensus meeting. The final approved recommendations standardize biologically-relevant histopathologic terminology for HPV-associated squamous intraepithelial lesions and superficially invasive squamous carcinomas across all lower anogenital tract sites and detail appropriate use of specific biomarkers to clarify histologic interpretations and enhance diagnostic accuracy. A plan for disseminating and monitoring recommendation implementation in the practicing community was also developed. The implemented recommendations will facilitate communication between pathologists and their clinical colleagues and improve accuracy of histologic diagnosis with the ultimate goal of providing optimal patient care.

Men who have sex with men (MSM) are at greatly increased risk of human papillomavirus (HPV)-associated anal cancer. Screening for the presumed cancer precursor, high-grade anal intraepithelial neoplasia (AIN), followed by treatment in a manner analogous to cervical screening, has been proposed. We aimed to assess available data for anal HPV disease that can inform pre-cancer screening programmes. We searched PubMed, OVID Medline, and Embase for all studies published before Nov 1, 2011, that reported prevalence and incidence of anal HPV detection, AIN, and anal cancer in MSM. We calculated summary estimates using random-effects meta-analysis. 53 studies met the inclusion criteria, including 31 estimates of HPV prevalence, 19 estimates of cytological abnormalities, eight estimates of histological abnormalities, and nine estimates of anal cancer incidence. Data for incident HPV and high-grade AIN were scarce. In HIV-positive men, the pooled prevalence of anal HPV-16 was 35·4% (95% CI 32·9-37·9). In the only published estimate, incidence of anal HPV-16 was 13·0% (9·6-17·6), and clearance occurred in 14·6% (10·2-21·2) of men per year. The pooled prevalence of histological high-grade AIN was 29·1% (22·8-35·4) with incidences of 8·5% (6·9-10·4) and 15·4% (11·8-19·8) per year in two estimates. The pooled anal cancer incidence was 45·9 per 100,000 men (31·2-60·3). In HIV-negative men, the pooled prevalence of anal HPV-16 was 12·5% (9·8-15·4). Incidence of HPV-16 was 11·8% (9·2-14·9) and 5·8% (1·9-13·5) of men per year in two estimates. The pooled prevalence of histological high-grade AIN was 21·5% (13·7-29·3), with incidence of 3·3% (2·2-4·7) and 6·0% (4·2-8·1) per year in two estimates. Anal cancer incidence was 5·1 per 100,000 men (0-11·5; based on two estimates). There were no published estimates of high-grade AIN regression. Anal HPV and anal cancer precursors were very common in MSM. However, on the basis of restricted data, rates of progression to cancer seem to be substantially lower than they are for cervical pre-cancerous lesions. Large, good-quality prospective studies are needed to inform the development of anal cancer screening guidelines for MSM. Australian Government Department of Health and Ageing. Copyright © 2012 Elsevier Ltd. All rights reserved.