Screening for cervical cancer implies early diagnostics of high-risk intraepithelial lesions (HSIL) and the initial microinvasive changes. The method which is recognized as the gold standard for this screening is exfoliative cytology - PAP test. Recommendations for safe time interval that should repeat cytology screening are 3 years. In this interval, calculated risk of carcinoma is 0,8%. It is known that the sensitivity of conventional PAP test is from 30 - 85%. The influence of subjective factors and errors in collecting and interpreting the findings reduce the validity of the test. According to official recommendations, it is considered that the repetition of PAP test in the three-year interval is safe in screening of cervical carcinoma. The aim of this study was to determine the reliability of conventional PAP test in screening for cervical cancer and to determine what percentage of the HPV test can increase the reliability of PAP test in screening for cervical cancer.
The study entered 39 patients, which occurred in 2017, for surgical treatment of HSIL and invasive cancer (IC). In all patients, the PAP test was done and also HPV PCR test. A history of time interval since the last normal NILM findings as well as data on the possible contact or irregular bleeding, are also entered in the statistical analysis of data.
Only 20,51% of patients had a PAP test done before three years or more. 35,8% of the patients had normal test result less than 3 years and 43,58% of them done the PAP test a year ago and the result was also normal - NILM. From the 20 patients with IC, 16 of them (80%) had normal PAP test less than 3 years. 40% (8 patients) had a normal PAP test a year ago. Analysis of the documents that they have been brought with them, as part of preoperative preparation, showed in 11 patients (28,2%) with HSIL and IC normal PAP findings. From these 11 false-negative cytological findings (FNF), in 4 (36,36%) has been diagnosed HSIL and in 7 (63,6%) IC. From these 7 with IC, in 4 patients with (57%) FNF, histological type was adenocarcinoma. A total sensitivity of cytology was 71.79%. HPV testing in 38 patients (97%) with HSIL and IC was positive. Only one patients with HSIL (2.56%) had a negative HPV test. HPV test increased sensitivity of cytology for 25.64%.
The three year cytological screening with conventional PAP test, as a alone test, is not reliable for screening of cervical cancer. HPV test, in combination with cytology, increases the overall sensitivity of cytology for 25.64%. Both of them are very important for early treatment of premalignant intraepithelial lesions.
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