Human papillomavirus infection of the uterine cervix: histological appearances in 28 cases identified by immunohistochemical techniques.

Twenty eight biopsy specimens of the cervix showed positive immunohistochemical staining when treated with an antiserum raised against an internal capsid antigen of human papillomavirus (HPV). Histological examination of adjoining sections from the same blocks showed a much wider range of abnormalities than those already described in association with HPV infection. The picture was usually diagnostic. It rested chiefly on identifying the koilocyte--the cell with the perinuclear halo that carries the viral antigen in its nucleus--but abnormal keratinisation was also a feature. The accompanying epithelial findings ranged from normal to CIN III (cervical intraepithelial neoplasia). The latter was of an unusual but distinct appearance, in which cytoplasmic maturation was preserved to some degree but in which gross nuclear atypia was seen in all layers of the epithelium.