Anal intraepithelial neoplasia: a review of terminology, differential diagnoses, and patient management

Hum Pathol. 2023 Feb:132:56-64. doi: 10.1016/j.humpath.2022.07.005. Epub 2022 Jul 16.

Abstract

Despite the knowledge of etiological association with high-risk human papilloma viruses and high-risk patient cohorts, the incidence of anal squamous cell carcinoma has continued to rise. The known precursor lesion (in particular, high-grade squamous intraepithelial lesion) makes it amenable to screening and surveillance strategies. However, the diagnosis of anal intraepithelial neoplasia suffers from interpretation challenges leading to high interobserver variability, along with numerous differential diagnoses and lingering terminology issues. Proper treatment of anal lesions requires accurate diagnosis, and while a variety of modalities are available for treatment, the rate of recurrence remains high and each modality has its own set of side effects and complications. The aim of this review article is to outline the diagnostic considerations and provide practical tips for diagnosing anal squamous intraepithelial lesions.

Keywords: Anal intraepithelial neoplasia; Anus; HPV; Histology; Squamous intraepithelial lesion.

Publication types

  • Review

MeSH terms

  • Anal Canal / pathology
  • Anus Neoplasms* / diagnosis
  • Anus Neoplasms* / pathology
  • Anus Neoplasms* / therapy
  • Carcinoma in Situ* / diagnosis
  • Carcinoma in Situ* / pathology
  • Carcinoma in Situ* / therapy
  • Carcinoma, Squamous Cell* / diagnosis
  • Carcinoma, Squamous Cell* / etiology
  • Carcinoma, Squamous Cell* / therapy
  • Diagnosis, Differential
  • Humans
  • Papillomavirus Infections* / complications
  • Papillomavirus Infections* / diagnosis