The predictive value of sonographic images of follicular lesions - a comparison with nodules unequivocal in FNA - single centre prospective study.

BACKGROUND: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Effective Use of microRNA, BRAF and Sonographic Risk Assessment in Bethesda III Thyroid Nodules Requires a Different Approach to Nodules with Features of Nuclear Atypia and Other Types of Atypia.

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.

The Presence of Hypoechoic Micronodules in Patients with Hashimoto's Thyroiditis Increases the Risk of an Alarming Cytological Outcome.

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.

Validation of Four Thyroid Ultrasound Risk Stratification Systems in Patients with Hashimoto's Thyroiditis; Impact of Changes in the Threshold for Nodule's Shape Criterion.

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.

The efficiency of elastography in the diagnostics of follicular lesions and nodules with an unequivocal FNA result.

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.

Analysis of clinical significance of equivocal thyroid cytology with a special consideration for FLUS category - five years of new classification of FNA results.

INTRODUCTION: The diagnostic category of follicular lesion of undetermined significance (FLUS) was intended to allow selection of cases with low risk of malignancy from all smears with indeterminate, suspicious cytology (ISC), which can potentially take advantage from repeat fine-needle aspiration (rFNA). Aim of the study was a comparison of the risk of malignancy related to FLUS nodules and other nodules with ISC: suspected follicular neoplasm (SFN) and suspected malignancy (SM), as well as analysis of the usefulness of assessing ultrasonographic malignancy risk features (UMRF) in nodules with ISC. MATERIAL AND METHODS: We analysed UMRF, rFNA, and results of histopathological examination (H) in 441 FLUS, 135 SFN, and 72 SM nodules. RESULTS: The frequency of exposing cancer in H in FLUS nodules was 5.9%, and when cytological follow up was also included it was 2.9%. rFNAs made the diagnosis more precise in 72.7% of FLUS, and in 5.2% it was diagnosis/suspicion of cancer. The incidence of cancer in SFN nodules was 8.2%, in SM nodules with suspicion of papillary cancer - 61.1%, and in nodules with suspicion of other or unspecified malignancy - 53.8% (p < 0.0001 FLUS vs. both groups). The presence of calcifications is the only independent UMRF for nodules with ISC (OR 4.7). Features of importance are also microcalcifications (OR 3.8), especially in the SM group, and taller-than-wide-shape (OR 2.2). FLUS and SFN nodules are characterised by particularly low value of assessing suspicious margins; analysis of hypoechogenicity is of low value in SFN nodules, like suspected vascularisation in SFN and SM nodules. CONCLUSIONS: The risk of cancer in FLUS and SFN nodules is lower than in SM nodules. rFNAs of FLUS nodules make the diagnosis more precise in more than 70% of cases and are effective in revealing cancers. UMRFs present variable diagnostic value depending on the subcategory of ISC.