Ultrasonographic Characteristics of Thyroid Nodules in Predicting the Malignancy and the Role of the Cytopathologist

Abstract

Aim: It is very important to determine the correct nodules which should be evaluated with thyroid fineneedle aspiration biopsy (FNAB) and avoid unnecessary operations. In this study, we aimed to analyze the relationship and the compatibility between thyroid FNAB results with ultrasonographic features and the role of the pathologist who examines the specimens.Material and Methods: 458 patients with nodules who underwent FNAB were included in the study. The relationships between the ultrasonographic features (echogenicity, shape, margin, vascularization and calcification) and biopsy results and, the factor of the pathologist were evaluated retrospectively. Since there was no Bethesda VI (malignant) result, analyzes were made among 5 subgroups. FNAB procedures were considered as, inadequate or nondiagnostic, benign, atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS), follicular neoplasia and suspicion of malignancy.Results: Solid internal structure, irregular margin, hypoechogenicity, presence of microcalcification, nodules with taller than wide (AP> T) were found significantly different between the subgroups of Bethesda classification system (p<0.01, for all features). All suspicious features were found more common in the malignant suspicious nodules than the benign nodules. 63 of 211 preparations (29.8%), which were evaluated as Bethesda I and Bethesda III, were reported by a single pathologist, and statistically significant differences were found in comparison to the other pathologists (p<0.01). Conclusion:Ultrasonography features that include malignancy risk correlate with cytopathology results. The incidence of thyroid nodules is gradually increasing and therefore, it is important to perform biopsies according to ultrasonographic risk stratification. Moreover, working with a thyroid specialist pathologist may minimize the indeterminate results.