Immunocytochemistry of p16INK4a and Ki-67 as adjunctive method for routine gynecological cytology of mild and moderate dysplasia

Especially the cytological diagnoses of mild and moderate dysplasia are often followed by unnecessary stigmatization of patients and uncertainty in further clinical follow-up and therapy. Data from 222 patients including additional investigations by high-risk human papillomavirus (HPV) testing and combined immunocytochemistry for p16(INK4a) and Ki-67 were documented, including cytological and histological follow-up. Overall for cytology, high risk HPV testing and dual staining the following characteristics concerning the presence of cervical intraepithelial neoplasia (CIN) 2+ were calculated (in %): sensitivity 100, 95.8 and 92.4, specificity -, 23.3 and 72.8, positive predictive value 53.6, 59.1 and 79.7, negative predictive value -, 82.8 and 89.3, respectively. There was a statistically significant advantage for higher specificity and positive predictive value for dual staining, especially for cytological diagnosis of low grade dysplasia. An objective individual risk stratification of patients with cytology of mild or moderate dysplasia is not available but the uncertainty in the management of these patients will be clearly reduced.