Cervicogram as a Primary Screening Test Hans Hinselman in Hamburg, Germany applied colposcopy to the screening of cervical cancer for the first time in 1925. The advantages of colpos- copy are its ability to locate the low infiltrated lesions, to determine the extent of the lesions, and its high accuracy. Colposcopy has been used widely as a diagnostic tool, together with the Pap test, for cervical cancer and premalignant lesions. However, high false positive rates for colposcopy have been reported. Although this is due to the interpretation skill of specialists, it is also influ- enced by trichomonas or papilloma virus infec- tion.20 The limitations of colposcopy are that it re- quires experienced specialists with excellent in- terpretation skills, it requires expensive equip- ments, and only a limited number of patients can be examined as the test takes a long time. Fur- thermore, as the equipments cannot be moved readily, its application to mass screening and general screening is limited.8,9 Cervicography is a screening method developed in 1981 by Adolf Stafl in the Wisconsin University College of Medicine.8,21,22 Although its principles are based on colposcopy, cervicography obtains objective test materials with a special camera by taking pictures of the outside of cervix, deve- loping the pictures, and then interpreting the pictures by 2 - 3 cervicography specialists. Com- pared with colposcopy, the advantages of cervi- cography are that it is relatively inexpensive, the equipment is moved readily, the image can be objectively interpreted by experienced specialists, and the method has high reproducibility.10 Thus, cervicography has been reported to be applicable to mass screening for cervical cancer and to facilitate the selection of therapy for patients with atypical cells detected by the Pap test.11 In scre- ening for cervical cancer by cervicography, techni- cal defects were detected in about 1-10% cases. This is primarily due to blood masking the view of the cervix. The disadvantage of cervicography is its high false positive rate: 26-38.1% false positives have been reported. In our study, the false positive rate was 29.3%.23-25 Other disadvan- tages are its limitation in examining the cervical canal and tissue specimens cannot be obtained.6 The advantage of the Pap test is its ability to obtain cervical epithelial cells. However, as specimens from a large area of the cervix cannot be obtained, the cervico-vaginal smear may gener- ate the false negative results. In contrast, cervico- graphy can verify a small pathological lesion. The shortcomings of cervicography are that it can not examine the inside of cervix and its effectiveness is decreased in old patients whose transitional zone can not be visualized or in patients whose cervix has been previously treated. Therefore, it has been reported that the supplemental use of these two tests is advantageous and the combina- tion of the two tests is expected to reduce the false negative rate and increase the detection rate.25,26 In our study, however, the sensitivity of cervi- cography was 39.6% lower than the Pap test. In addition, the false negative rate of cervicography was higher than the Pap test (49% vs. 35.4%). Therefore, cervicography could not overcome the disadvantages of the Pap test, although the speci- ficity of cervicography was higher than the specificity of the Pap test (79.2% vs. 64.6%). For the combination of the Pap test with cervico- graphy, compared with the Pap test alone, the sensitivity was higher (79.3% vs. 72.0%), the negative predictive value was higher (66.3% vs. 64.6%), and the false negative rate was lower (33.7% vs. 35.4%). Yet, the difference was not statistically significant. For the combination of the two tests, however, the specificity was lower (51.4% vs. 64.6%), the positive predictive value was lower (64.7% vs. 72%), and the false positive rate was higher (32.6% vs. 28%). Concerning the cost and the effectiv- eness, the combination of two tests as a primary screening method may be require its reconsi- deration for clinical application. When comparing the effectiveness of cervicography on the patients classified based on their Pap test results, its diagnostic accuracy was not superior, except for the specificity. For patients with a normal Pap test and with cytology testing performed on those patients with positive cervicography, the false positive rate was as high as 58.6% and the sensitivity rate was low, 26.1%. The data showed that unnecessary cervical biopsy was performed in many cases. In patients with positive Pap test, on the other hand, the false negative rate was 67.3% on cervicography. Thus, for patients with negative cervicography, without additional tests, pathological lesions were not detected in many Yonsei Med J Vol. 46, No. 2, 2005