P104 - Anal Intraepithelial Neoplasia detection on Routine Colonoscopy: Review of 3550 patients

Abstract Podium Presenter(s)

• 

  Saleh Busbait

  Colorectal Surgery Fellow
  Henry Ford Providence Hospital
  Southfield, MI, United States

  All disclosed relationships have been reviewed and managed prior to the start of this activity. Any relevant relationships will be listed below. This individual has no financial relationships to disclose

Author(s)

• MA

  Maryam Aleissa, MBBS (she/her/hers)

  colorectal surgery fellow
  Henry Ford providence hospital
  Michigan State University College of Human Medicine
  southfild, MI, United States

  All disclosed relationships have been reviewed and managed prior to the start of this activity. Any relevant relationships will be listed below. This individual has no financial relationships to disclose
• 

  Koby Herman, MD

  Fellow
  Henry Ford Providence Hospital
  Henry Ford Providence Hospital
  Ferndale, MI, United States

  Disclosure information not submitted.
• 

  Jai Singh, MD

  Colorectal Surgery Fellow
  Henry Ford Providence Hospital
  Rochester Hills, MI, United States

  Disclosure information not submitted.
• 

  Guriqbal Bhullar, DO MHA

  General Surgery Resident
  Franciscan Health
  Franciscan Health
  Westland, MI, United States

  Disclosure information not submitted.
• ED

  Ernesto R. Drelichman, MD

  President Elect Medical Staff
  Henry Ford Health
  rochester hills, Michigan, United States

  Disclosure information not submitted.
• VM

  Vijay k. Mittal, MD

  Hepatobiliary surgeon
  Henry Ford Providence Hospital
  southfild, Michigan, United States

  Disclosure information not submitted.
• MF

  Molly Flanagan Synowicz, MD

  General Surgery Resident
  Henry Ford Providence Hospital
  southfild, Michigan, United States

  Disclosure information not submitted.

Senior Author(s)

• 

  Jasneet S. Bhullar, MD, MS, FACS, FASCRS.

  Clinical Associate Professor of Surgery MSU/CHM, Program Director Colorectal Surgery Fellowship MSU
  Henry Ford Health
  Henry Ford- MSU Colorectal Surgery Fellowship, MI
  Rochester Hills, Michigan, United States

  All disclosed relationships have been reviewed and managed prior to the start of this activity. Any relevant relationships will be listed below. This individual has no relevant financial relationships.

Purpose/Background: Human papillomavirus (HPV) infection is prevalent, with a lifetime likelihood of infection exceeding 80% among sexually active individuals who have not received the HPV vaccine. Published data have focused on recognized populations that are at a high risk of developing AIN. AIN is typically asymptomatic and can only be diagnosed through specific examination. Since 60-70% of anal squamous cell carcinomas (ASCC) present at an advanced stage and progression from AIN III occurs over a median of approximately 5 years, early detection is critical.

Methods/Interventions: This is a retrospective study performed at a single institution in Michigan, USA. A consecutive series of 3550 colonoscopies carried out between January 2021 and July 2025 were retrospectively reviewed. All patients underwent screening colonoscopies wherein the anorectum and transition zones were inspected for AIN lesions with a narrow band imaging, during retroflexion. Biopsies were carried out when suspected abnormalities were found, after which the specimens were studied by gastrointestinal pathologists. All patients with confirmed AIN were referred to high resolution anoscopy HRA with treatment.

Results/Outcomes: The study included 3,550 patients of which 41 patients (1.2%) revealed lesions suspicious for AIN (19 males, 22 females; median age 70 years). The histopathology results showed that 24 patients (58.5%) had low-grade AIN, 16 patients (39.0%) had high-grade AIN and 1 patient (2.4%) had invasive squamous cell carcinoma. Nearly half of patients (48.8%) were HIV-negative, confirming immunocompetent status. No biopsy-related complications were reported.

Conclusion/Discussion: Although infrequent, detection of AIN during routine colonoscopy is feasible and clinically valuable, including in immunocompetent individuals. Routine colonoscopy with retroflexion using a narrow band imaging offers a good opportunity for AIN detection, even in immunocompetent patients. The detection and treatment of AIN may lead to ASSC prevention. It worth incorporating AIN screening during routine colonoscopy into daily practice as well as in teaching fellow and residents to how identifying these lesions.

Colonoscope image showing AIN III.
A, slightly raised areas of thickened distal rectal mucosa. B, irregular blood vessel mosaic appearance of the mucosa during retroflexion using narrow-band imaging, Pathology revealed it as AIN III in immunocompetent patient.