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Published on: July 25, 2017
Increased sensitivity of anal cytology in evaluation of internal compared with external lesions
Fernando U Garcia1, Marian M Haber, Jeffrey Butcher
1Department of Pathology, Graduate Hospital, Drexel University School of Medicine, Philadelphia, Pennsylvania, USA. fg24@drexel.edu
Insights
Thickened keratin layers on external anal lesions can hinder accurate diagnosis using anal brush sampling. This study found hyperkeratosis interferes with adequate sampling and grading of these lesions.
Area of Science:
- Gastroenterology
- Oncology
- Infectious Diseases
Background:
- Anal squamous intraepithelial lesions (ASIL) are a concern in human immunodeficiency virus (HIV)-seropositive individuals.
- Accurate diagnosis of ASIL is crucial for timely intervention and management.
Purpose of the Study:
- To evaluate the effect of keratin on the diagnostic accuracy of internal and external anal brush sampling.
- To determine if keratinization impacts the reliability of brush cytology for ASIL detection.
Main Methods:
- 46 HIV-seropositive patients with known anal lesions underwent both internal and external anal brush sampling prior to biopsy.
- Cytological analysis of brush samples and histological examination of biopsies were performed.
- Sensitivity and specificity of brush sampling for ASIL were calculated for internal and external lesions.
Main Results:
- Internal lesions showed a sensitivity of 91.1% and specificity of 42.8% for ASIL.
- External lesions demonstrated a sensitivity of 79.4% and specificity of 100%.
- Markedly thickened keratin and low cellularity on cytology were significantly more prevalent in external lesions (p < 0.0001).
Conclusions:
- Hyperkeratosis significantly interferes with the adequate sampling and accurate grading of external anal lesions using brush cytology.
- The findings suggest limitations in using anal brush sampling for external lesions, particularly those with significant keratinization.
Objective:
To investigate the impact of keratin on the accuracy of internal and external anal brush sampling of known lesions.
Study Design:
A group of 46 human immunodeficiency virus (HIV)-seropositive patients underwent external and internal anal brush sampling before biopsy of known lesions. RESULTS; A total of 92 ThinPrep (46 external, 46 internal) an 211 biopsies were examined. The sensitivity and specificity for internal lesions positive and negative for anal squa mous intraepithelial lesion (ASIL) was 91.1% and 42.8%, respectively; and for external lesions was 79.4% and 100%, respectively. Low cellularity on cytology and markedly thickened keratin on biopsy were significantly more common in external compared with internal lesions (p < 0.0001).
Conclusion:
We conclude that hyperkeratosis interferes with adequate sampling and accurate grading of external anal lesions by brush sampling.
