High Grade Squamous Intraepithelial Neoplasia

**Semantic type:** Neoplastic Process

**Definition:** A precancerous neoplastic process characterized by the presence of moderate or severe dysplastic cytological changes which extend to the upper part of the squamous epithelium. Maturation at the surface of the squamous epithelium may or may not be present. Representative examples include the high grade esophageal squamous intraepithelial neoplasia, high grade cervical squamous intraepithelial neoplasia, high grade vaginal intraepithelial neoplasia, and high grade vulvar intraepithelial neoplasia.

**Synonyms:** - HSIL - HSIL - High-Grade Squamous Intraepithelial Lesion - Squamous intraepithelial neoplasia, high grade - high-grade squamous intraepithelial lesion