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Review
. 2016 Mar;29(1):57-64.
doi: 10.1055/s-0035-1570394.

Screening, Surveillance, and Treatment of Anal Intraepithelial Neoplasia

Affiliations
Review

Screening, Surveillance, and Treatment of Anal Intraepithelial Neoplasia

Kevin C Long et al. Clin Colon Rectal Surg. 2016 Mar.

Abstract

The prevalence of anal intraepithelial neoplasia has been increasing, especially in high-risk patients, including men who have sex with men, human immunodeficiency virus positive patients, and those who are immunosuppressed. Several studies with long-term follow-up have suggested that rate of progression from high-grade squamous intraepithelial lesions to invasive anal cancer is ∼ 5%. This number is considerably higher for those at high risk. Anal cytology has been used to attempt to screen high-risk patients for disease; however, it has been shown to have very little correlation to actual histology. Patients with lesions should undergo history and physical exam including digital rectal exam and standard anoscopy. High-resolution anoscopy can be considered as well, although it is of questionable time and cost-effectiveness. Nonoperative treatments include expectant surveillance and topical imiquimod or 5-fluorouracil. Operative therapies include wide local excision and targeted ablation with electrocautery, infrared coagulation, or cryotherapy. Recurrence rates remain high regardless of treatment delivered and surveillance is paramount, although optimal surveillance regimens have yet to be established.

Keywords: anal intraepithelial neoplasia; carcinoma; human papillomavirus.

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Figures

Fig. 1
Fig. 1
Proposed algorithm for surveillance of AIN.

References

    1. Siegel R, Naishadham D, Jemal A. Cancer statistics, 2012. CA Cancer J Clin. 2012;62(1):10–29. - PubMed
    1. Fenger C, Nielsen V T. Intraepithelial neoplasia in the anal canal. The appearance and relation to genital neoplasia. Acta Pathol Microbiol Immunol Scand [A] 1986;94(5):343–349. - PubMed
    1. National Cancer Institute, DCCPS, Surveillance Research Program SSB Surveillance, Epidemiology, and End Results (SEER) Program Available at: www.seer.cancer.gov. Research Data (1973–2012).
    1. Palefsky J M. Human papillomavirus infection and anogenital neoplasia in human immunodeficiency virus-positive men and women. J Natl Cancer Inst Monogr. 1998;23:15–20. - PubMed
    1. Machalek D A, Poynten M, Jin F. et al.Anal human papillomavirus infection and associated neoplastic lesions in men who have sex with men: a systematic review and meta-analysis. Lancet Oncol. 2012;13(5):487–500. - PubMed