Expression of the proliferating cell nuclear antigen in cervical neoplasia.

The expression of the proliferating cell nuclear antigen (PCNA) was examined to determine the proliferative activity of the cells in nonneoplastic and neoplastic lesions of the uterine ectocervix. Formalin-fixed, paraffin-embedded tissue sections of uterine cervix including normal, metaplasia, condyloma, intraepithelial neoplasia and invasive squamous cell carcinoma were stained immunohistochemically using monoclonal antibody to PCNA. The percentage of PCNA-positive cells was significantly higher in premalignant and malignant lesions of the uterine cervix than in nonneoplastic lesions. Furthermore, the growth fraction of tumor cells as detected by PCNA was increased in accordance with the progression of neoplasia. The results of this study suggest that the cell proliferation index as detected immunohistochemically using PCNA may be a useful adjunct to histological diagnosis of various grades of dysplasia.