Verification of doubtful PAP smear results of women included in the screening program in the Podlaskie province

Abstract

Verification of uncertain PAP-smear results in a group of women covered by the cervical screening program in the Podlaski province. The main aim of the study was to identify CIN (Cervical Intraepithelial Neoplasia) lesions present, with varying degrees of severity in women with cytological diagnosis of ASCUS (atypical squamous cells of undetermined significance), LSIL (low grade squamous intraepithelial lesion), and ASC-H (atypical squamous cells - cannot exclude high grade squamous intraepithelial lesion). The study evaluated 101 cervical smears taken from the vaginal part of the cervix in a group of screened women in the Podlaski province. Cytological evaluation was performed according the Bethesda System. We analyzed abnormal smears selected from a total of 7296 cytological examinations performed during 2012 at the University Center for Pathomorphological and Genetic - Molecular Diagnosis, Medical University in Białystok. The cytological results which were of interest to us included 19 cases with ASCUS, 59 with LSIL, and 23 with ASC-H, as well as with morphological features of the presence of Human Papilloma Virus (HPV). Staining was performed using CINtecPLUS test according to the manufacturer's instructions. CINtecPLUS is a immunocytochemical test based on specially designed monoclonal antibodies (E6H4TM) that let us identify protein p16ink4a within the cervical smear Additionally the diagnostic kit was provided with antibodies for diagnosing the presence of Ki-67 protein, a known marker of cell proliferation. The result was considered positive when staining of the nucleus and the cytoplasm appeared in red and brown, respectively. All abnormal results were eventually verified by histological examination of the tissue taken from cervical lesions by diagnostic-therapeutic procedure following colposcopic evaluation of cervical lesion topography In the group of cytological smears with ASCUS, the diagnosis was positive in 5 cases (26.3%), negative in 14 (73.7%). In the group with the diagnosis of LSIL, the cytology results were positive in 32 cases (54.2%), negative in 27 (45.8%). In the cytological diagnosis of ASC-H there were 20 positive (87%) and 3 negative (13%) results. Test CINtecPLUS could be a helpful tool in the final diagnosis of cervical abnormality in patients with the cytological diagnosis of ASCUS, LSIL and ASC-H. The combination of conventional cytological test and CINtecPLUS can help create a new procedure algorithm for cases with abnormal or ambiguous cytological screening results. It could be especially useful in a group of young women of childbearing age, when it is common to avoid a more radical treatment of cervical lesions.