Type of Preparation: Histology Magnification: High Interpretation: HSIL Cytomorphologic Criteria: Histologic section demonstrating "full thickness" involvement of the epithelium by dysplastic cells without significant maturation. Note mitoses in upper third of the epithelium and apoptotic bodies. Explanatory Notes: Histologic appearance of CIN 3 (severe dysplasia/ carcinoma in situ), apoptosis.