Alterations of E-cadherin expression in cervical intraepithelial neoplasias and invasive carcinomas of the uterine cervix have been described by some authors but their clinical significance has not yet been clarified. Archival specimens of 27 normal cervical epithelia, 15 atypical cells of undetermined origin (ASCUS), 53 low-grade squamous intraepithelial lesions (LSIL), 19 high-grade squamous intraepithelial lesions (HSIL) and six invasive squamous carcinomas were evaluated for E-cadherin expression. The cytological material was processed using liquid based cytology (ThinPrep technique) and immunostained for E-cadherin. All HPV infections (koilocytes) showed strong cell membranous E-cadherin expression. In HSIL a strong decrease in E-cadherin expression and heterogeneous distribution was noticed. In the relatively small number of squamous cell carcinomas of the cervix studied, a significant decrease or loss in E-cadherin expression, predominantly cytoplasmic, was noted. We concluded that decreased E-cadherin expression appears to be a useful parameter of malignant potential of cervical lesions. E-cadherin immunoexpression could provide an additional criterion in correlation with cyto- and histomorphology and colposcopy to define high grade CIN lesions.