Liquid‐based FNAC of the thyroid

Abstract

BACKGROUND:The aims of this study were to analyze cytomorphological features of Tripath PREP (BD SurePath, Burlington, NC) preparations in thyroid nodules and to examine adequacy and accuracy of SurePath and frozen sections for both clinical outcome and histological diagnosis when applicable.METHODS:Gathered during a period of 4 years, 712 SurePath specimens of the thyroid were included. Histological (n = 207) or clinical follow‐up (n = 505) was available in all cases. During the same period, 253 frozen sections of surgical thyroid resection specimens were also assessed. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated.RESULTS:Sensitivity was 77% for SurePath and 29% for frozen section; specificity was 81% for SurePath and 100% for frozen section; accuracy was 80% for SurePath and 90% for frozen section. One hundred seventy‐eight (25%) SurePath patients were considered unsatisfactory for diagnosis. In this study, sensitivity, specificity, and accuracy were comparable for SurePath and other reported results of liquid‐based thyroid cytology. Presence of free colloid or pure cystic changes favored a benign diagnosis. Cellular smears with nuclear atypia of papillary carcinoma allowed an overt diagnosis of malignancy.CONCLUSIONS:The authors concluded that SurePath is a reliable technique for assessment of thyroid nodules and offers the advantage of easy identification of colloid and atypical nuclei. Supplementary frozen section analysis should be limited to an FNAC diagnosis of suspicious for papillary carcinoma. Cancer (Cancer Cytopathol) 2011. © 2010 American Cancer Society.

Diagnostic value of liquid‐based cytology with fine needle aspiration specimens for cervical lymphadenopathy

“…We had analyzed and shown that the unsatisfactory or nondiagnostic rate, the sensitivity and specificity of LBC using LBCPREP2™ in the diagnosis of TC were 9.1%, 95.2%, and 100%, respectively (unpublished data). Previous reports have shown a diagnostic sensitivity of 76.3–96.1% and a specificity of 54.9–81% in thyroid nodule with TC for FNA with LBC using either ThinPrep™ or SurePath™ system 36, 37, 38, 39. The unsatisfactory or nondiagnostic rate of the LBC systems ranges from 8.2% to 22.5% in the literature 34, 37, 39.…”

“…In the ThinPrep™ system, cells are collected in a methanol‐based solution (Cytolyt™) and are then transferred on to a positively charged slide with a gentle positive pressure 23. In contrast, in the SurePath™, cells are collected in an ethanol‐based solution (CytoRich™), centrifuged, and are then slowly sedimented onto a poly‐ l ‐lysinated slide 36. These systems are useful for the occasional processing of a large amount of samples at large‐scale medical centers.…”

“…Therefore, cytopathologist should be cautious in interpreting LBC results if this is the only methodology employed. Several morphological differences were shown and observed among LBCPREP2™, ThinPrep™, and SurePath™ preparations which reflect different sampling devices, collection media, and processing techniques 17, 36, 40. However, all the LBC methods have common and excellent findings such as reduced incidence of air‐drying artifacts, cleaner background, even distribution of cells over a smaller slide area, and increased cellularity.…”

Liquid-Based Cytology in Fine-Needle Aspiration Biopsies of the Thyroid Gland

“…In series where the direct-to-vial method is used, and all of the cellular material is therefore submitted for cytologic analysis, the average cellularity is generally higher than with the split-sample method and the rates of inadequacy and false positivity decrease significantly [9,13,15,16]. Regarding the results of Geers and Bourgain [17] using the SurePath method, these authors did not achieve good results in terms of the inadequacy rate but there might be some reasons related to the technical differences between ThinPrep and SurePath (see Inadequate Smears). Nevertheless, they claimed a significant reduction of the false-negative diagnoses.…”

“…The LBC ThinPrep-processed slides may show a few ill-preserved cells at the periphery of the circle because transfer from the preservative solution to the specific slide requires positive pressure which may give rise to cellular artifacts. SurePath, according to Geers and Bourgain [17], yields an inadequacy rate of 25% in thyroid aspiration cytology. This result can probably be attributed to the low sedimentation rate of the colloid droplets which might hinder their inclusion in the final slide [17].…”