Multiinstitutional Study for the Development of Cervical Cancer Screening Model with New Cervicography, Pap Smear and HPV-DNA Test

Kim, S J; Park, C K; Lee, H P; Namkoong, S E; Kang, S B; Saw, H S; Lee, J K; Kim, S N; Kim, J W; Bae, S N; Kim, C J; Lee, K H; Lee, S Y; Kim, I H; Lee, C; Lee, J N

Abstract

OBJECTIVE
The false negative rate of conventional cytology is reported to range from 18 to 45%. It is necessary to develop more effective screening strategies that would ideally be more accurate than conventional cytology. This study is designed to investigate the potential of conventional cytology, cervicography, HPV-DNA testing and their combinations as primary screening techniques for cervical neoplasia. The purpose of this project is to develop the models and guidelines for screening tools of cervical cancer of the uterus by evaluating sensitivity, specificity and cost-effectiveness of all the screening methods. STUDY DESIGN: We conducted a screening of random sample of women who visited the department of OB-Gyn. of five different major university hospitals such as Catholic University Hospital, Korea University Hospital, Seoul National University Hospital, Yeonsei University Hospital and Pochon CHA University Bundang CHA Hospital, from May 1, 1996 to April 30, 1999. In a cohort women with an age range of 20 to 70 who underwent routine cytologic screening at Catholic University, Hospital Bundang CHA General Hospital and local clinics from April 1, 1996 to Decomber 31, 2000. cervicography (n=417,125) and testing for HPV-DNA (n=1,347) by the hybrid capture assay were studied for the ability of the cervical cancer screeuing. A new cervicography system with Kim's classification which was developed by Prof. Kim Seung Jo as an adjunctive method for the cervical cancer screening was applied in this cohort study. And then, accuracy, effectivencess, cost-effectiveness of the single or combined screening method were analysed. RESULT: Sensitivity and specificity of Pap smear were ranged from 55.6% to 83.1% and 72.8% to 88.3% respectively. The combination of Pap smear and cervicography had sensitivity from 89.7% to 98.6%, specificity from 68.2% to 93.2%. With combination of Pap smear, HPV DNA test and cervicography, sensitivity became also highest accuracy among all screening methods from 92.8% to 98.8%. Considering medical charges for diagnosis and social cost occurred by false positive and false negative results, the most cost-effective diagnostic modality was thought to be the combination of Pap smear and cervicography(91,433 won). In patients who were diagnosed as LSIL, colposcopic examination confirmed progression to high grade intraepithelial lesion(HSIL) in 10.7% patients, persistence of LSIL in 55% patients during the 3 year follow-up period. Accuracy of the screening for cervical cancer and CIN can significantly be improved by cytology with "new cervicography" rather than cytology alone. We concluded that cervicography can be important adjunctive tests for cervical cytology, improving the effectiveness of cervical screening by allowing a more sensitive detection of cervical neoplasia.