Efficacy of liquid cytology, on the one hand, and those of standard one, appraisal of high risk of cancer by polymerase chain reaction (PCR) of human papillomavirus infection and immunohistochemical assay of p16ink4 high risk in cervical carcinoma diagnosis, on the other, was evaluated PCR of high risk of cancer (dysplasia-free) was detected in 73% (n = 73), CIN I-II--78%, CIN II-III--89%, CIN III and carcinoma--100%. p16ink4 was not detected in dysplasia-free cases and it was--(16%) in CIN I-II, (89%) CIN II-III, (90%) CIN III and (100%)--in carcinoma. Hence, unlike p16ink4 expression (p < or = 0.001), a correlation between the increase in the number of those infected with papillomavirus was not significantly higher than that of dysplasia grade (p < or = 0.05). It is suggested that combined use of liquid cytology and immunohistochemical assay of p16ink4 is more effective.