The Utility of Contrast-Enhanced Ultrasound (CEUS) in Assessing the Risk of Malignancy in Thyroid Nodules.

BACKGROUND: Ultrasonography is a primary method used in the evaluation of thyroid nodules, but no single feature of this method predicts malignancy with high accuracy. Therefore, this paper aims to assess the utility of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of thyroid nodules. METHODS: The study group comprised 188 adult patients (155 women and 33 men) who preoperatively underwent CEUS of a thyroid nodule classified as Bethesda categories II-VI after fine-needle aspiration biopsy. During the CEUS examination, 1.5 mL of SonoVue contrast was injected intravenously, after which 15 qualitative CEUS enhancement patterns were analysed. RESULTS: The histopathologic results comprised 65 benign thyroid nodules and 123 thyroid carcinomas. The dominant malignant CEUS features, such as hypo- and heterogeneous enhancement and slow wash-in phase, were evaluated, whereas high enhancement, ring enhancement, and a slow wash-out phase were assessed as predictors of benign lesions. Two significant combinations of B-mode and CEUS patterns were noted, namely, hypoechogenicity with heterogeneous enhancement and non-smooth margins with hypo- or iso-enhancement. CONCLUSIONS: The preliminary results indicate that CEUS is a useful tool in assessing the risk of malignancy of thyroid lesions. The combination of the qualitative enhancement parameters and B-mode sonographic features significantly increases the method's usefulness.

Ultrasound and cytopathological characteristics of thyroid tumours of uncertain malignant potential - from diagnosis to treatment.

INTRODUCTION: The latest World Health Organization (WHO) classification from 2022 distinguishes the division of low-risk thyroid neoplasms such as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), follicular tumour of uncertain malignant potential (FT-UMP), and well-differentiated tumour of uncertain malignant potential (WDT-UMP). The final diagnosis is made postoperatively according to histopathologic results. The aim of the study was the assessment of ultrasonographic and cytopathological features of borderline lesions to predict low-risk tumours preoperatively and plan the optimal treatment for that group of patients. MATERIAL AND METHODS: A total of 35 patients (30 women; 5 men), aged 20-81 years with a mean age of 49 years, were enrolled in the study. The study evaluated 35 focal lesions of the thyroid gland, classified as low-risk neoplasms according to the WHO 2022 classification: FT-UMP (n = 21), NIFTP (n = 7), and WDT-UMP (n = 7). Ultrasonographic features of nodules including contrast-enhanced ultrasound (CEUS) and elastography were assessed by 2 specialists, and the risk of malignancy was evaluated according to EU-TIRADS-PL classification. RESULTS: Of the 35 focal thyroid lesions, most were categorised as low or intermediate risk of malignancy according to EU-TIRADS-PL, with dominant category 3 [n = 13 (37.2%)] and category 4 [n = 15 (42.8%)]. High-risk category 5 was assessed in 7 lesions (20%). In cytopathology nodules were categorised as follows (Bethesda System TBSRTC 2023): Bethesda II (n = 4), Bethesda III (n = 2), Bethesda IV (n = 25), Bethesda V (n = 3), and Bethesda VI (n = 1). In the CEUS study, contrasting patterns dominated compared to the surrounding parenchyma, such as enhancement equal to the parenchyma (66.6%) or intense (28.5%), heterogeneous (61.9%), centripetal (42.8%), or diffuse (57.1%) with fast (33.3%) or compared to parenchyma contrast wash-in (42.8%) and its fast (33.3%) or comparable to thyroid parenchyma wash-out (52.3%). CONCLUSIONS: The study indicates that lesions with uncertain malignant potential typically present features suggesting low to intermediate risk of malignancy based on EU-TIRADS-PL classification, with dominant cytopathologic Bethesda IV category. However, 20% of lesions were assessed tas EU-TIRADS-PL category 5. Low-risk tumours, including NIFTP, FT-UMP, and WDT-UMP, require careful observation and monitoring post surgical treatment due to their potential for recurrence and metastasis. The preoperatively prediction of borderline tumour may play an important role in proper treatment and follow-up.

Fine needle aspiration biopsy of parathyroid; is it meaningful? A cytologic study of 81 cases with histological and clinical correlations.

BACKGROUND: Recognizing the parathyroid gland and distinguishing the parathyroid from thyroid lesions in fine needle aspiration (FNA) is challenging. This study aimed to identify cytomorphologic features suggestive of parathyroid origin and to assess the utility of cytopathology in conjunction with ancillary tests in the identification of parathyroid glands. MATERIALS AND METHODS: Ultrasound (US) guided FNA of parathyroid gland and lesions in 81 patients were reviewed concerning clinical history and correlated to histopathologic findings in available cases. FNA smears were evaluated for cellularity, architectural patterns, cellular and nuclear features, and background of the smears. In 78 cases, FNA was supplemented by a measurement of parathormone (PTH) levels in the needle washout fluid (FNA-PTH assay) and/or GATA3/PTH/chromogranin-A immunostainings. RESULTS: Sixty-four cases were diagnosed cytologically as parathyroid lesions in conjunction with FNA-PTH assay and/or immunocytochemical examinations. In an additional nine cases, a diagnosis of parathyroid lesions was rendered after repeated FNA with FNA-PTH assay. The histolopathologic diagnosis of surgically excised cases (n = 75) included parathyroid adenoma (60 cases), atypical parathyroid adenoma (4 cases), parathyroid hyperplasia (10 cases), and parathyroid carcinoma (1 case). Major cytological findings of parathyroid tissue included high cellularity, scattered naked nuclei, cribriform and three-dimensional clusters, stippled chromatin, and oxyphilic cytoplasm while papillary pattern or colloid-like material was identified in three cases respectively. No nuclear grooves or inclusions were seen in any case. CONCLUSIONS: High cellularity scattered naked nuclei, cribriform and three-dimensional patterns, stippled chromatin and oxyphilic cytoplasm are cytomorphologic features that favour parathyroid origin. A combination of these features with FNA-PTH assay and/or GATA3, PTH, and chromogranin-A immunostainings on cytologic specimens aid in the identification of parathyroid glands and the distinguishing of parathyroid from thyroid lesions.

Thyroglobulin measurements in washouts of fine-needle aspiration biopsy in the monitoring of patients with differentiated thyroid carcinoma.

INTRODUCTION: Approximately 35% patients with papillary thyroid carcinoma (PTC) and 13% with follicular thyroid carcinoma (FTC) present with metastases of cervical lymph nodes (LNs) at the time of diagnosis. In addition, 15-20% of patients treated with total thyroidectomy develop, after an interval of five years, metastases to the neck LNs on ultrasound examination. Fine-needle aspiration biopsy (FNAB) represents the gold standard technique for the detection of cervical LNs metastases. The aim of the study was to evaluate the diagnostic performance of the technique of thyroglobulin (Tg) measurement of washout FNAB (FNAB-Tg) in diagnostics of LNs metastases in different groups of patients with differentiated thyroid carcinoma (DTC). MATERIAL AND METHODS: Two hundred FNAB-Tg samples from 200 patients [158 women; 42 men; mean age 51.37 ± 16.77 (53)] diagnosed with DTC were examined for the assessment of the diagnostic utility of FNAB-Tg from suspicious LNs. FNAB-Tg ranged from 1.96 to 5000 ng/mL in metastatic LNs [mean; 1510 ± 1486 ng/mL (958.5)] and from 0.04 to 635.9 ng/mL in nonmetastatic LNs [mean; 57.86 ± 319.19 ng/mL (1.96)], p < 0.001. RESULTS: The most accurate diagnostic performance was displayed for the concentration of 33.28 ng/mL in FNAB-Tg with AUC of 0.91 and high sensitivity and specificity (0.92 and 0.93). FNAB-Tg in conjunction with the cytopathological examination of suspicious LNs in differentiated thyroid carcinoma (DTC) patients increases the diagnostic accuracy of FNAB (sensitivity 0.99; specificity 0.99; AUC 1.00). CONCLUSIONS: FNAB-Tg may be particularly useful in detecting LN metastases in DTC patients, and in differential diagnosis of various LN metastasizing malignancies. The combination of FNAB and FNAB-Tg measurement has high specificity and sensitivity in the detection of LN metastases of DTC.

Risk factors of permanent hypoparathyroidism after total thyroidectomy and central neck dissection for papillary thyroid cancer: a prospective study.

INTRODUCTION: Inadvertent removal of, or damage to the parathyroid glands in the course of operations on the anterior neck compartment are responsible for over 80% of cases of chronic hypoparathyroidism (HypoPT). This study searched for factors related to the development of permanent HypoPT after total thyroidectomy and central neck lymphadenectomy in patients with thyroid carcinoma. MATERIAL AND METHODS: In total, 89 of 103 screened patients met the study's criteria and were put under prospective one-year observation. Demographic and surgical factors as well as the biochemical parameters of mineral homeostasis, controlled both preoperatively and postoperatively, were subject to statistical analysis. In line with contemporary guidelines, postoperative hypocalcaemia, rather than an abnormally low serum parathormone (PTH) concentration, was considered a diagnostic criterion of HypoPT. RESULTS: On postoperative day one (POD1), serum concentration of PTH decreased below the normal range (< 12 pg/mL) in 29 patients and was undetectable in 19 patients (< 6 pg/mL). At one year postoperatively, 12 patients with undetectable POD1 PTH required treatment for hypocalcaemia and were diagnosed with permanent hypoPT. All the other patients regained normocalcaemia. Relative risk of permanent HypoPT associated with undetectable POD1 PTH was 88.75. A significant difference in median POD1 serum calcium concentration between the patients with undetectable POD1 PTH and those with detectable POD1 PTH was found (p < 0.001). The difference between the POD1 serum calcium in patients with permanent or transient HypoPT in the subgroup with undetectable POD1 PTH did not reach the level of statistical significance (median, 1.82 mmol/L vs. 1.96 mmol/L). At one month postoperatively, in patients who later developed permanent HypoPT, serum calcium was lower than it was in all other patients (p = 0.167). At one year postoperatively, serum concentration of PTH was in the normal range in 10 of 12 patients with permanent HypoPT; however, it was significantly lower than it had been before the operation and distinctly lower than it was in patients who regained normocalcaemia. The number of parathyroid glands either dissected or autotransplanted did not affect the development of permanent HypoPT. CONCLUSIONS: Undetectable POD1 PTH is an important risk factor of permanent HypoPT. The main cause of permanent HypoPT was irreversible damage to the left in situ parathyroid glands.

Hyaline matrix in hyalinizing trabecular tumor: Findings in fine-needle aspiration smears.

Hyalinizing trabecular tumor (HTT) is a rare neoplasm which usually follows an indolent clinical course. The cytologic diagnosis of HTT can be challenging as these neoplasms share cytomorphological features with other thyroid neoplasms and paraganglioma. In fine-needle aspiration (FNA) smears a diagnosis of papillary thyroid carcinoma (PTC) or suspicion of PTC is often made. Herein we report cytologic findings in two patients with HTT examined by FNA. The key to a correct diagnosis is the recognition of a hyaline and colloid/amyloid-like material in the background of the smears. Immunocytochemical examination showing aberrant membranous and peripheral cytoplasmic staining for MIB-1 can help in rendering a correct diagnosis.