File:Histopathology of anal epithelium with normal histology, low-grade<unk> , high-grade<unk>  and squamous cell carcinoma.Histopathology of anal epithelium:A. Normal histology, negative for anal intraepithelial neoplasia lesion (AIN)B. Low-grade<unk> , here called low-grade squamous intraepithelial lesion (LSIL)C. High-grade<unk> , here called high grade squamous intraepithelial lesion (HSIL)D. Squamous cell carcinoma, infiltrating the stroma (middle and left in image), and HSIL (right in image)<unk> , a term becoming increasingly referred to as intraepithelial neoplasia, is the sum of various disturbances of<unk>  proliferation and differentiation as seen microscopically. Individual cellular features of<unk>  are called<unk>  atypia. Examples of<unk>  include cervical intraepithelial neoplasia – a disorder commonly detected by an abnormal pap smear) consisting of an increased population of immature (basal-like) cells which are restricted to the mucosal surface, and have not invaded through the basement membrane to the deeper soft tissues. Analogous conditions include vaginal intraepithelial neoplasia and vulvar intraepithelial neoplasia. Metanephric dysplastic hematoma of the sacral region is a dysplastic overgrowth observed in infants.
Epithelial dysplasia
Mammoplasia
Intraepithelial neoplasia
Atypical hyperplasia
Papilloma
Squamous intraepithelial lesion
Field cancerization
Squamous metaplasia