Objective: To evaluate the efficacy of liquid-based cytology (ThinPrep Pap Test) for cervical carcinoma screening in a high incidence area, Xiangyuan county of Shanxi province.
Methods: This study was performed on 1997 women residing in Xiangyuan county, a high incidence of cervical carcinoma. Exfoliative cervical samples and subsequent colposcopic biopsies were taken from all subjects. Cervical samples were collected into a liquid buffer for both ThinPrep Pap Test cytologic screening and human papilloma virus (HPV) DNA test. All tests were carried out independently and blindly of which the results were compared with those of HPV DNA detection and colposcopic biopsies.
Results: When the cytologic diagnosis of atypical squamous cells of determined significance (ASCUS) was taken as the detection threshold and compared with the "standard" biopsy, the ThinPrep slides were able to detect 100%(12/12) of squamous cell carcinoma (SCC) and 93.2% high grade squamous intraepithelial lesions (HSIL) which included 96.8% (30/31) CIN III, 90.7% (39/43) CIN II and 72.4%(92/127) low grade squamous intraepithelial lesions (LSIL). When cytologic diagnosis of HSIL was used as the detection threshold, the ThinPrep slides were able to detect 100% (12/12) SCC and 87%(27/31) CIN III.
Conclusion: Cervical specimens collected into a liquid buffer are suitable for both cytologic screening and human papilloma virus test. The ThinPrep cytology demonstrates a high sensitivity for the detection of high grade squamous intraepithelial lesions and squamous cell carcinoma.