Current concepts of intraepithelial neoplasia in the uterine cervix (CIN).

The unifying concept of precancerous events in the epithelia of the uterine cervix is reviewed in the light of epidemiologic and morphologic observations. The role of human papillomavirus (HPV) infection as a factor in the genesis of precancerous states and carcinoma of the uterine cervix is assessed. Although cytologic, histologic, ultrastructural and molecular biologic data support the concept of HPV as an oncogenic virus, the precise mechanisms linking the infection with cancer are not known at this time. A hypothesis of the presumed sequence of events is presented.