Two-tiered system to classify cytology and histology of squamous intraepithelial lesions. Cervical intraepithelial neoplasia (CIN) grade 1, anal intraepithelial neoplasia (AIN) grade 1, and condyloma (genital warts) are termed low-grade squamous intraepithelial lesions (LSIL). CIN/AIN grades 2 and 3 are termed high-grade squamous intraepithelial lesions (HSIL). This classification reflects the distinct biology underlying LSIL and HSIL[1].
Adapted from: Bonnez W. Papilloma virus. In: Clinical Virology, Richman DD, Whitley RJ, Hayden FG (Eds), 3rd Edition, ASM Press, Washington DC 2009, page 623.
Reference:
- Blaustein's Pathology of the Female Genital Tract, 5th ed, R.J. Kurman (Ed), Springer-Verlag 2002.