Objective: New classification of the thyroid fine-needle aspiration biopsy (FNAB) results tries to stratify the risk of malignancy of thyroid follicular lesions using 'follicular lesion of undetermined significance' (FLUS) subcategory. Clinical significance of this category in the endemic (or post-endemic) areas has not been clearly established. Design: The aim of the study was to determine the risk of malignancy for FLUS as well as to evaluate ultrasound (US) malignancy risk features (MRF) in such nodules in comparison with 'suspicious for neoplasm' (SFN) and 'benign lesions' (BL). Methods: The US images and cytological diagnoses of 589 thyroid follicular lesions were analysed from January 2010 to July 2012. Cytological follow-up was assessed in 110 cases and surgical one in 100 cases. Results: FLUS was diagnosed in 340 cases (3.8% of all cytological diagnoses and 57% of thyroid follicular lesions). Altogether, clinical and/or surgical follow-up revealed thyroid cancer in 3.2% patients with FLUS nodules. Repeat FNAB led to more specific diagnosis in 74.4% of FLUS (3.5%, papillary cancers or their suspicion; 2.3%, SFN; 68.6%, BL). The histopathological examination showed thyroid cancer in 6.4% cases of FLUS and 7.0% of SFN and follicular adenoma in 8.5% of FLUS and 11.6% of SFN (NS, FLUS vs SFN). FLUS showed MRF of intermediate values between BL and SFN; SFN more often than FLUS showed at least two MRF (53 vs 30%, P < 0.0001). Conclusions: The risk of cancer in FLUS in areas with recently corrected iodine supply is low. In such areas, repeated biopsy leads to more precise cytological diagnosis in about 3/4 cases. European Journal of Endocrinology 168 621-630

The aim of the study was to validate thyroid US malignancy features, especially the nodule’s shape, and selected Thyroid Imaging Reporting and Data Systems (EU-TIRADS; K-TIRADS; ACR-TIRADS, ATA guidelines) in patients with or without Hashimoto’s thyroiditis (HT and non-HT groups). The study included 1188 nodules (HT: 358, non-HT: 830) with known final diagnoses. We found that the strongest indications of nodule’s malignancy were microcalcifications (OR: 22.7) in HT group and irregular margins (OR:13.8) in non-HT group. Solid echostructure and macrocalcifications were ineffective in patients with HT. The highest accuracy of nodule’s shape criterion was noted on transverse section, with the cut-off value of anteroposterior to transverse dimension ratio (AP/T) close to 1.15 in both groups. When round nodules were regarded as suspicious in patients with HT (the cut-off value of AP/T set to ≥1), it led to a three-fold increase in sensitivity of this feature, with a disproportionally lower decrease in specificity and similar accuracy. Such a modification was effective also for cancers other than PTC. The diagnostic effectiveness of analyzed TIRADS in patients with HT and without HT was similar. Changes in the threshold for AP/T ratio influenced the number of nodules classified into the category of the highest risk, especially in the case of EU-TIRADS.

Introduction: The aim was to assess the usefulness of strain elastography (SEG) in the diagnostics of two groups of thyroid nodules (TNs): follicular lesions (FL) with low malignancy risk (< 20.0%) and low percentage of papillary carcinomas (PTCs) among cancers as well as TNs with unequivocal cytology (UC) and high percentage of PTCs among cancers. Material and methods: 168 TNs were analysed and eventually surgically treated: 100 UC (50 benign and 50 malignant — 90.0% PTCs) and 68 FL (60 benign, 8 malignant — 50.0% PTCs). Elasticity score (ES) and strain ratio (SR) were evaluated, and their effectiveness was compared with the evaluation of the number of ultrasound malignancy risk features (NoUMRFs). Results: In the UC group the evaluation of mean values of SR and ES in both sections (meanSR, meanES) was more efficient than NoUMRFs analysis (AUC: 0.903 and 0.869 vs. 0.754, p < 0.05). The following thresholds: meanSR ≥ 2.01, meanES ≥ 2.5, NoUMRFs ≥ 2, were related to the increased malignancy risk in nodules (OR: 45.0; 23.2; 5.4, respectively), but only meanSR ≥ 2.01 was an independent risk factor (OR: 20.3; SEN: 86.0%, SPC: 88.0%). In the FL group, only the evaluation of tSR (SR assessed in transverse section) had the value of AUC > 0.7, and only the set of features: tSR ≥ 1.7 and NoUMRFs ≥ 1 increased the malignancy risk in nodules (OR: 12.0; SEN: 75.0%, SPC: 75.0%). Conclusions: SEG is more reliable than conventional US in the diagnostics of TNs. The efficacy of SEG decreases with lowering percentage of PTCs among cancers. But in FL nodules SEG may support the selection of nodules for surgical treatment. Introduction: The aim was to assess the usefulness of strain elastography (SEG) in the diagnostics of two groups of thyroid nodules (TNs): follicular lesions (FL) with low malignancy risk (< 20.0%) and low percentage of papillary carcinomas (PTCs) among cancers as well as TNs with unequivocal cytology (UC) and high percentage of PTCs among cancers. Material and methods: 168 TNs were analysed and eventually surgically treated: 100 UC (50 benign and 50 malignant — 90.0% PTCs) and 68 FL (60 benign, 8 malignant — 50.0% PTCs). Elasticity score (ES) and strain ratio (SR) were evaluated, and their effectiveness was compared with the evaluation of the number of ultrasound malignancy risk features (NoUMRFs). Results: In the UC group the evaluation of mean values of SR and ES in both sections (meanSR, meanES) was more efficient than NoUMRFs analysis (AUC: 0.903 and 0.869 vs. 0.754, p < 0.05). The following thresholds: meanSR ≥ 2.01, meanES ≥ 2.5, NoUMRFs ≥ 2, were related to the increased malignancy risk in nodules (OR: 45.0; 23.2; 5.4, respectively), but only meanSR ≥ 2.01 was an independent risk factor (OR: 20.3; SEN: 86.0%, SPC: 88.0%). In the FL group, only the evaluation of tSR (SR assessed in transverse section) had the value of AUC > 0.7, and only the set of features: tSR ≥ 1.7 and NoUMRFs ≥ 1 increased the malignancy risk in nodules (OR: 12.0; SEN: 75.0%, SPC: 75.0%). Conclusions: SEG is more reliable than conventional US in the diagnostics of TNs. The efficacy of SEG decreases with lowering percentage of PTCs among cancers. But in FL nodules SEG may support the selection of nodules for surgical treatment.

The aim of the study was to identify a possible relation between various ultrasonographic (US) appearances of Hashimoto′s thyroiditis (HT) and the risk of obtaining an alarming cytology of coexisting nodules. The study included 557 patients with HT, who had been referred for fine needle aspiration biopsy (FNA). We divided US patterns of HT (UP-HT) into eight groups: (a) Hypoechoic (compared to submandibular glands), homogeneous/fine echotexture; (b) hypoechoic, heterogeneous/coarse echotexture; (c) marked hypoechoic (darker than strap muscles), heterogeneous/coarse echotexture; (d) heterogeneous echotexture with hyperechoic, fibrous septa; (e) multiple, discrete marked hypoechoic areas (sized as 1 to 6 mm); (f) normoechoic pseudo-nodular areas; (g) echostructure similar to connective tissue; (h) thyroid parenchyma with no signs of HT. Indications for a surgical treatment resulting from the FNA outcome (categories IV–VI of Bethesda System for Reporting Thyroid Cytopathology) were identified only in patients with variants b, c, and e of UP-HT, but merely the “multiple, discrete marked hypoechoic areas” variant significantly increased the odds of obtaining such cytology (OR:5.7). The presence of the “normoechoic pseudo-nodular areas” variant significantly increased the odds for the benign cytology (OR:1.7). There are significant differences in the frequency of obtaining an alarming cytology in relation to the UP-HT variant.

The aim of the study was to analyze the diagnostic usefulness of the combined assessment of the ultrasound risk category of the nodule (evaluated with EU-TIRADS system), the presence of BRAF V600E mutation and the expression of selected microRNAs (miR-146b, miR-221 and miR-222) in Bethesda category III thyroid nodules, separately for cases with nuclear atypia (AUS-nuclear) and cases with other types of atypia (AUS-other). We evaluated 161 nodules (66 AUS-nuclear and 95 AUS-other) with known results of postoperative histopathological examination. The rate of cancer and the rate of PTC among cancers were nearly three times higher in the AUS-nuclear than the AUS-other group. For AUS-nuclear nodules, the most effective diagnostic panel included, in addition to repeat FNA, the assessment of BRAF V600E mutation and the expression of miR-146b and miR-222 (sensitivity: 93.5%, specificity: 80.0%). For AUS-other nodules, a two-step procedure was most effective: at the first stage, forgoing surgical treatment in subjects with a benign repeat FNA outcome, and, at the second stage, the assessment of miR-222 expression and the EU-TIRADS category (sensitivity: 92.3%, specificity: 76.8%). The optimal use of molecular methods in the diagnostics of category III thyroid nodules requires a separate approach for nodules with nuclear atypia and nodules with other types of atypia.

To determine the diagnostic efficacy of ultrasonographic malignancy risk features (UMRFs) in follicular lesions (FL) in a population with low risk of malignancy in FL and to compare it with a similar analysis in a group of patients with unequivocal cytology (UC): benign lesion (BL) or malignant neoplasm (MN). Presence of UMRFs (hypoechogenicity, solid echostructure, taller-than-wide shape, pathological vascularization, irregular margins, microcalcifications and macrocalcifications) and their sets were assessed in 322 FL: 202 follicular lesions of undetermined significance (FLUS) and 120 suspicious for follicular neoplasm (SFN) and 300 nodules with UC: 200 BL and 100 MN, subsequently evaluated histopathologically. Cancers were confirmed in 100% nodules in MN group (89.0% of them were papillary carcinomas - PTC), in 6.4% FLUS nodules (69.2% PTC), and in 10.8% SFN nodules (30.8% PTC). In the UC group all UMRFs occurred more frequently in cancers than in benign lesions. In the FL group only calcifications were found in cancers more frequently – macro and microcalcifications together: 34.6 vs. 11.5% (p = 0.001) and isolated macrocalcifications: 26.0 vs. 6.8% (p = 0.001); the presence of those features increased the basic risk of malignancy in FL more than 2 times. The presence of at least 2 of the following URMFs: hypoechogenicity, solid echostructure, any type of calcifications and suspected shape, additionally improved sensitivity. Evaluation of UMRFs in FLs is less effective than in nodules with UC, and its effectiveness decreases parallel to the decrease in percentage of PTCs among malignant neoplasms and to the increase of the percentage of adenomas among benign nodules. The presence of macrocalcifications in such FLs significantly increases the basic risk of malignancy in these nodules.