Comparative analysis of conventional Papanicolaou smear, fluid-based thin-layer method and cervicography

Kim, Yu Ri; Kim, Young Tae; Kim, Sung Hoon; Kim, Jae Hoon; Kim, Jae Wook; Park, Yong Won

Abstract

OBJECTIVE
The aim of this study was to evaluate the diagnostic performance of Papanicolaou smear, a fluid-based thin-layer method and cervicography as a primary screening test of cervical cancer.
METHODS
Among all patients screened by cervicography from January 2003 to Jun 2004, 357 patients who were examined by the Pap smear or ThinPrep Pap test and cervicography as a screening procedure for cervical cancer and taken by the subsequent colposcopy directed biopsy as required, were analyzed with a receiver operating characteristic (ROC) curves and divided into two groups: conventional Pap group (n=256) and ThinPrep group (n=101).
RESULTS
ThinPrep group showed higher sensitivity (86.0%>64.0%), higher negative predictive value (78.4%>65.0%), lower false negative rate (21.6%<35.0%), but lower specificity (66.0%<79.5%), lower positive predictive value (66.2%<78.8%), higher false positive rate (33.8%> 21.2%). Cervicography showed no significant difference between each group. In ThinPrep group, ROC curves showed the AUC of ThinPrep 0.848, the AUC of cervicography 0.585. ThinPrep group was higher with statistical significance (P=0.0001). In conventional Pap group, the result of ROC curves showed the AUC of conventional Pap 0.750, the AUC of cervicography 0.680. Conventional Pap group was somewhat higher but there was no statistical significance (P=0.0975).
CONCLUSION
ThinPrep Pap test showed significantly higher diagnostic accuracy than cervicography. However, conventional Pap test revealed somewhat better screening performance than cervicography without statistical significance. Therefore, the ThinPrep Pap test might be an effective screening test in detecting precancerous lesion of the uterine cervix.