Introduction: Due to the importance of early diagnosis in cervical cancer and high number of false negative results of papanicolaou smear as screening method, in recent years several studies has been done to find an appropriate test. Fluid-based methods and especially Thinprep have the highest potential for reducing this problem and increasing the adequacy of specimens. The aim of this study was comparison of papanicolaou fluid-based/thin layer smears and accompanied cell blocks with conventional pap smear in terms of adequacy of the specimen.

Methods: In this prospective study, the results of 140 thin layer smears prepared from April 2002 to March 2003 were compared with those of 100 conventional pap smears prepared within the same time in terms of adequacy of the specimen. Pap smear was prepared using spatula and cytobrush. Cervex-brush was used for sampling with thin layer method and the specimen was prepared using Cyto-tek equipment. In thin layer method, a cell block slide was prepared using the rest of the specimen. The smears were interpreted using Bethesda system.

Results: The number of occasions of "satisfactory but limited" (SBL) estimated by thin layer method and accompanied cell blocks, 17 (12.1%), was comparable with those obtained by conventional pap smear method, 39 (39%). The number of unsatisfactory cases by thin layer method and accompanied cell block was estimated 6 (4.3%), compared with that of conventional pap smear test which was 9 (9%). The reduction in the number of unsatisfactory cases and SBL under thin layer method with cell block, and the consequent increase in satisfactory smears was statistically significant by Chi-square test (P <0.05). The number of cases having endocervical cell/T-zone component only in cell block slides was 30 (25%).

Conclusion: Fluid-based thin layer method along with cell block improves the adequacy of the specimen, and in turn result in reduction of unsatisfactory and SBL cases. Complementary cell block method lead to finding more endocervical components/T-zone as well as increased number of satisfactory specimens.

Hakim Research Journal 9(1): 22-27.