p53 immunostaining and HPV DNA detection by PCR in cervical intraepithelial neoplasia: clinical implications of a combinated evaluation.

We analyzed p53 immunoreactivity and clinical outcome in a series of cervical intraepithelial neoplasias (CIN), with respect to HPV DNA positivity. Cervical biopsy samples were obtained from 86 women who attended our Colposcopic Service from January 1993 to June 1994 due to abnormal pap-smear suspicious for CIN and/or human papillomavirus infection. Forty-one women with histologically confirmed CIN were included in the study. p53 positivity was immunohistochemically detected by monoclonal antibody anti-human p53 (pAb D0-7, Dako Denmark; dilution 1:50), and expressed as the percentage of positive cells. p53 positivity was observed in 78% of CIN lesions. In particular, all the HPV DNA-negative dysplasias expressed p53 protein while only 12 out of 21 (57%) HPV DNA-positive were p53 immunoreactive; (P = .003) the p53 immunostaining was also significantly higher in HPV DNA-negative than in positive CIN (P = .049). By analyzing p53 positivity with respect to clinical-pathologic evolution of the disease, among HPV DNA-negative cases, progressive dysplasia had significantly higher values of p53 immunostaining when compared to persistent and/or regressive lesions (P = .002). These findings imply that p53 immunostaining, when analyzed with respect to HPV DNA status, may help to understand the behavior of dysplastic lesions and define their therapeutic approach. Extensive p53 staining in HPV DNA-negative CIN is probably correlated with a high risk of progression.