Clinical Usefulness of SurePath(TM) Liquid-based Cytology in Thyroid Fine Needle Aspiration: Comparison with the Conventional Smear in Diagnostic Efficacy and Applicability of BRAF Mutation Test

BACKGROUND: Recently, liquid-based cytology (LBC) has been introduced as an alternative to the conventional smear (CS) technique in thyroid fine needle aspiration, due to its diagnostic convenience. METHODS: We assessed 77 cases of thyroid fine needle aspiration using the SurePath(TM) method (SP) as LBC and CS via split-sample techniques. BRAF mutation tests were carried out via polymerase chain reaction and pyrosequencing immediately after diagnosis or a delay of more than one year. RESULTS: In a comparison between SP and CS, the rate of concordance between SP and CS was as high as 84.4% (kappa value, 0.754). In comparison with histologic diagnosis, the overall sensitivity was 100% for both. The specificity was 62.5% for SP and 56.3% for CS. Relative to CS, papillary carcinomas on SP slides revealed more accentuated nuclear irregularities, nucleoli, and reduced nuclear size. In contrast to CS, the delayed BRAFV600E mutation test using SP slides after 1-2 years failed. The use of new primers amplifying shorter product size could help the delayed test achieve success. CONCLUSIONS: Differences in the diagnostic efficacy of SP and CS were negligible. The failure of the delayed BRAF mutation test on the SP slides might be associated with DNA degradation.

The Usefulness of SurePath(TM) Liquid-Based Smear in Sono-Guided Thyroid Fine Needle Aspiration; a Comparison of a Conventional Smear and SurePath(TM) Liquid-Based Cytology / 대한세포병리학회지

Sono-guided fine needle aspiration (FNA) of the thyroid is widely used, but the aspirated samples are typically not well preserved and low cellularity makes diagnosis difficult in many cases. The object of the current study is to evaluate the adequacy and diagnostic accuracy of the use of SurePath(TM) liquid-based cytology (SP-LBC) in the sonoguided fine needle aspiration of the thyroid nodule and to compare its use with that of the use of a conventional smear (CS). A total of 172 sono-guided FNAs of thyroid nodules from April to June, 2006 were prepared by the use of the split method with either SP-LBC or CS; the samples were stained with the use of hematoxylin-eosin (H&E) and Papanicolaou (Pap) stains. A cyto-histological correlation was performed in 69 (30 SP and 39 CS) cases that had been histologically confirmed. The rate of producing unsatisfactory slides by the use of the SP-LBC method (9.3%) was less than that of the use of the CS method (20.9%). The diagnostic accuracy of the SP method (93.3%) was better than that of the CS method (85.3%). The sensitivity and specificity of the SP method (94.4% and 92.3%) was better than that of the CS method (83.3% and 70%), respectively (p<0.05). The CS of sono-guided aspirated specimens had some unavoidable limitations related to inadequate sampling such as a bloody background, low cellularity and an indication that some clinicians smeared many useless slides (averaging four to ten slides), and that most slides showed only blood that included few follicular cells. The SP method resulted in more thinly smeared slides and showed cleaner background and greater cellularity than the use of the CS method. Each follicular cell shows superior nuclear detail, and more distinct cytoplasmic features than with the use of the CS method. SP-LBC appears to be an easy, highly accurate, and reliable cytological method for employ for a diagnostic approach of thyroid disease and thyroid nodules. The SP-LBC method is a suitable alternative to the CS method to overcome diagnostic difficulties.

A Comparision of Surepath(TM) Liquid-Based Smear with a Conventional Smear for Cervicovaginal Cytology-with Reference to a Histological Diagnosis / 대한세포병리학회지

This study was performed to compare Surepath(TM) liquid-based smear and a conventional cervicovaginal smear with reference to a histological diagnosis. A hybrid capture test (HCII) was also performed and analyzed. We collected matched cases for cervicovaginal cytology- histology: 207 cases for conventional cytology (CC) and 199 cases for liquid-based cytology (LBC). HCII was performed in 254 patients. When a cytological diagnosis of ASCUS or above (ASCUS+) is classified as positive and a histological diagnosis of LSIL+ is classified as positive, the sensitivity and specificity for LBC was 91.7% and 75.9%, respectively and the sensitivity and specificity for CC was 62.6% and 96.1%, respectively. When a cytological and histological diagnosis of LSIL+ is classified as positive, the sensitivity and specificity for LBC was 77.5 and 96.6%, respectively and the sensitivity and specificity for CC was 49.7% and 100%, respectively. When a histological diagnosis of LSIL+ is classified as positive, the sensitivity and specificity for HCII was 78.9% and 78.1%, respectively. The concordance ratio between the cytological and histological diagnosis was 80.4% (kappa=76.0) for LBC and 56.5% (kappa=55.1) for CC. LBC is more sensitive and less specific then CC, as a cytological cutoff level of ASCUS, but more sensitive and equally specific, as a cytological cutoff level LSIL or HSIL. LBC is more reliable with a high concordance ratio between the cytological and histological diagnosis.