Objective To evaluate the efficacy of selected ultrasound (US) features of thyroid focal lesions useful for establishing indications for fine-needle aspiration biopsy (FNAB) with regard to the lesion's size. Methods US imaging features of 1141 thyroid nodules (shape, echogenicity, pattern of blood flow, presence of microcalcifications and the presence of other nodules in the thyroid) and their palpability were compared with the post-operative histopathological outcomes. The efficacy of the selected sets of the features was assessed for small nodules (SN)≤15 mm and large nodules (LN)>15 mm, as well as separately for nodules≤10 mm. Results Logistic regression analysis showed that in SN hypoechogenicity (odds ratios, OR: 3.18), microcalcifications (OR: 19.12), solitary occurrence (OR: 3.29) and height-to-width ratio≥1 (OR: 8.57) were independent risk factors for malignancy. The optimal set of small lesions that should be biopsied includes all lesions presenting at least one of the above-mentioned features (sensitivity 98%, specificity 44%). In the LN group, the selection criteria based on the shape of lesions and hypoechogenicity were less sensitive than in the SN group, but they allowed further reduction in the number of performed FNABs. Large nodules primarily selected for FNAB should be hypoechoic, more tall then wide or contain microcalcifications (sensitivity 84%, specificity 72%). Conclusions The obtained results provide rationale for using features from the US examination in selecting both small and large nodules for FNAB. In the case of LN, the usefulness of sonographic features is less sensitive, but more specific than in the case of SN.

Significant advances have been made in thyroid can­cer research in recent years, therefore relevant clinical guidelines need to be updated. The current Polish guidelines “Diagnostics and Treatment of Thyroid Carcinoma” have been formulated at the “Thyroid Cancer and Other Malignancies of Endocrine Glands” conference held in Wisła in November 2015 [1]. Significant advances have been made in thyroid can­cer research in recent years, therefore relevant clinical guidelines need to be updated. The current Polish guidelines “Diagnostics and Treatment of Thyroid Carcinoma” have been formulated at the “Thyroid Cancer and Other Malignancies of Endocrine Glands” conference held in Wisła in November 2015 [1].

OBJECTIVE: The iodine status of the population of Poland has markedly improved over the past years. The aims of this paper were: (i) to examine the diagnostic value of fine-needle aspiration biopsy (FNAB) of the thyroid in goitre endemic regions (in conditions of improved iodine supply), and (ii) to find whether the changes in iodine supply have already influenced the clinical interpretation of cytological results. METHODS: Cytological diagnoses, based on 3782 aspirates, obtained from 3572 patients during the years 1985-1999, were verified by reference to the results of postoperative examinations. The relative occurrences of selected cytological results in 1992-1999 were also compared (patients not subjected to surgery were included). RESULTS: We have found that the frequency of neoplastic lesions significantly decreased throughout the examined period (P<0.02). The ratio of the papillary carcinoma frequency to the follicular carcinoma frequency increased from 1.7 during 1992-1993 up to 8.0 during 1998-1999 (P<0.05). The frequency of cytologically diagnosed chronic thyroiditis increased from 1.5% in 1992 to 5.7% in 1999 (P<0.001); the percentage of cytological diagnosis of "follicular neoplasm" decreased during the same time (P<0.001). The risk of malignancy significantly lowered in the cytological diagnoses of "follicular neoplasm" from 15% during 1985-1993 to 6% during 1996-1999 (P<0.05). CONCLUSIONS: The diagnostic value of FNAB during the period without proper iodine prophylaxis did not differ significantly from that during the last examined period. However, the changes in iodine supply have markedly and promptly affected the clinical significance of particular cytological results.

The aim was to compare the usefulness of selected thyroid sonographic risk-stratification systems in the diagnostics of nodules with indeterminate/suspicious cytology or unequivocal cytology in a population with a history of iodine deficiency. The diagnostic efficacy of ACR-TIRADS (the American College of Radiology Thyroid Imaging Reporting and Data Systems), EU-TIRADS (European Thyroid Association TIRADS), Korean-TIRADS, Kwak-TIRADS, AACE/ACE-AME-guidelines (American Association of Clinical Endocrinologists/ American College of Endocrinology-Associazione Medici Endocrinologi guidelines) and ATA-guidelines (American Thyroid Association guidelines) was evaluated in 1000 nodules with determined histopathological diagnosis: 329 FLUS/AUS (10.6% cancers), 167 SFN/SHT (11.6% cancers), 44 SM (77.3% cancers), 298 BL (benign lesions), 162 MN (malignant neoplasms). The percentage of PTC (papillary thyroid carcinoma) among cancers was higher in Bethesda MN (86.4%) and SM (suspicion of malignancy) nodules (91.2%) than in FLUS/AUS (57.1%, p < 0.005) and SFN/SHT (suspicion of follicular neoplasm/ suspicion of Hürthle cell tumor) nodules (36.8%, p < 0.001). TIRADS efficacy was higher for MN (AUC: 0.827–0.874) and SM nodules (AUC: 0.775–0.851) than for FLUS/AUS (AUC: 0.655–0.701) or SFN/SHT nodules (AUC: 0.593–0.621). FLUS/AUS (follicular lesion of undetermined significance/ atypia of undetermined significance) nodules assigned to a high risk TIRADS category had malignancy risk of 25%. In the SFN/SHT subgroup none TIRADS category changed nodule’s malignancy risk. EU-TIRADS and AACE/ACE-AME-guidelines would allow diagnosing the highest number of PTC, FTC (follicular thyroid carcinoma), HTC (Hürthle cell carcinoma), MTC (medullary thyroid carcinoma). The highest OR value was for Kwak-TIRADS (12.6) and Korean-TIRADS (12.0). Conclusions: TIRADS efficacy depends on the incidence of PTC among cancers. All evaluated TIRADS facilitate the selection of FLUS/AUS nodules for the surgical treatment but these systems are not efficient in the management of SFN/SHT nodules.

Purpose: Equivocal categories (III, IV, V) of the Bethesda System for Reporting Thyroid Cytology (BSRTC) are characterized by high variability of the estimated risk of malignancy. The aim of the study was to analyze the reproducibility of classification of nodules into an equivocal category and the frequency of malignancy (FoM) observed in such categories. Methods: Five experienced cytopathologists from three centers (A, B, C) independently performed reclassification of smears obtained from 213 thyroid nodules with equivocal routine cytology and known results of the postoperative histopathological examination. Results: The interobserver agreement among all cytopathologists was poor, with a Krippendorff’s alpha coefficient equaling 0.34. The intra-center agreement was higher than the inter-center (fair vs poor). Pathologists of the center A classified smears into categories II and III significantly less often and categories IV and V more often than pathologists of centers B and C. The joint FoM of nodules classified into any of categories IV–VI (regarded as an indication for surgery) was different among centers (A: 40.0%, B: 66.7%, C: 80.6%). The FoM of category III nodules with features of nuclear atypia (AUS) in center B and C was two times higher than that of other nodules of category III (FLUS), while in center A the FoM was similar. Conclusions: The use of published data on the risk of malignancy in nodules of particular BSRTC categories without concern for the uniqueness of the diagnostic center may lead to erroneous conclusions.

Purpose The aim was to find whether the presence of Hürthle cells (HC) in a smear influences the categorization of FNA results or the risk of malignancy (RoM) of particular categories of cytological diagnosis. Methods 25,220 FNA performed in a single center in years 2005–2017 were analyzed. Almost all the examined patients were exposed to moderate iodine deficiency for most of their lives. The distribution of FNA outcome categories was compared between two groups: with or without HC (HC and non-HC). The RoM was evaluated on the basis of postoperative histopathological examination (3082 patients). Results HC were found in 7.5% of diagnostic FNA. HC nodules were classified into categories II (78.2% vs. 91.9%, p < 0.0000) and VI (0.4% vs. 1.2%, p = 0.0017) less often than non-HC nodules, but more frequently to categories III (14.4% vs. 5.8%, p < 0.0000), IV (11.2% vs. 0.9%, p < 0.0000) and V (1.5% vs. 0.8%, p = 0.0013). There were no significant differences in RoM between HC and non-HC nodules. The RoM in HC and non-HC nodules of particular categories of the Bethesda system was as follows: II: 1.8% vs. 0.8%, III: 9.7% vs. 3.8% when only the last FNA was considered and 10.8% vs. 6.4% when the category III in any performed FNA was considered; IV: 12.7% vs. 10.9%; V: 41.7% vs. 58.2%; and VI: 100% vs. 96.9%. Conclusions HC nodules are classified into categories of equivocal cytological outcomes more often than nodules without HC. Nevertheless, the presence of HC in a smear does not significantly affect the RoM of FNA categories.