Fig. 2-25.

Squamous intraepithelial neoplasia. a Low magnification of squamous intraepithelial neoplasia. The lesion is visible as an iodine-unstained area measuring 3 mm in size. Histologically, the lesion is well demarcated. b High magnification. The tumor shows mild nuclear atypia with low cellular density and a regular arrangement of the basal layer. c Histology of biopsy specimen. The lesion is visible as an iodine-stained tan area measuring 5 mm in size. Histopathologically, a mildly thickened epithelium exhibits atypical cell proliferation in the lower two-thirds of the epithelium, but nuclear atypia is mild and the basal layer has a regular arrangement