ABSTRACT
PURPOSE: Fine needle aspiration cytology (FNAC) is the most important diagnostic method for thyroid nodule. Liquid based cytology (LBC) is currently being studied for diagnosing thyroid nodule. We investigated the diagnostic value of ThinPrep®-LBC for thyroid nodules. METHODS: From January 2010 to May 2010, 139 patients underwent thyroidectomy based on the FNAC smear results. From November 2010 to February 2011, 153 patients underwent thyroidectomy based on the FNAC smear and ThinPrep®-LBC results. We compared the postoperative pathologic results of the FNAC smear group and the FNAC smear+LBC group. RESULTS: In the FNAC smear group, there were 11.5% unsatisfactory results and 10.1% atypia with undetermined significance results. On the other hand, in the FNAC smear +LBC group, there were no unsatisfactory results and only 2.0% atypia with undetermined significance results. For the results of the diagnostic validity, the sensitivity was 77.7%, the specificity was 94.4% and the accuracy was 82.0% for the FNAC smear group. The false positive rate was 5.6% and the false negative rate was 22.3%. For the FNAC smear+LBC group, the sensitivity was 87.8%, the specificity was 92.9% and the accuracy was 88.2%. The false positive rate was 7.1% and the false negative rate was 12.2%. CONCLUSIONS: If LBC is carried out simultaneously with FNAC smear, the rate of unsatisfactory results and atypia with undetermined significance could be decreased compared with that of the FNAC smear only.