Thyroid fine needle aspiration: how to improve clinicians' confidence and performance with the technique

Washout CYFRA 21-1: A tool to improve diagnostic accuracy of fine needle aspiration in the diagnosis of metastatic lymph nodes in papillary thyroid cancer

Thyroid carcinoma has an increasing incidence of endocrine system cancers. Fine needle aspiration cytology (FNAC) and thyroglobulin (Tg) are the primary diagnostic modalities employed for assessing metastatic lymph nodes (LNs) in thyroid cancer. Due to the limited accuracy, rare patients benefited from these procedures. In this research, we aimed to discover a dependable biomarker that could increase the accuracy of FNAC's ability to diagnose metastatic LNs among patients suffering from papillary thyroid cancer (PTC). From March 2021 to July 2023, 99 LNs from PTC patients who had thyroid ultrasonography suspicions of metastases were examined. All patients underwent FNAC, washout Tg and CYFRA 21-1 measurements. Surgical histology and a subsequent FNAC were utilized to validate the outcomes of LNs. In our study, the optimal cut-off value for CYFRA 21-1 washout fluid was 1.145 ng/mL, with a specificity of 94.00 % (slightly lower than Tg and FNAC at 98 %). However, CYFRA 21-1 demonstrated significantly higher diagnostic sensitivity (85.71 %) and accuracy (86.41 %) compared to Tg (71.43 %, 81.55 %) and FNAC (69.39 %, 80.58 %). Furthermore, FNAC plus washout CYFRA 21-1 performed better in diagnosing the metastatic LNs in PTC than FNAC plus Tg, which may indicate a novel solution for metastatic LNs diagnosis in PTC.

Performance of Thyroid Fine-Needle Aspiration Biopsy in a Low- and Middle-Income Country

INTRODUCTION

The 6 categories of the Bethesda System for Reporting Thyroid Cytology (TBSRTC) with associated risk of malignancy (ROM) provide evidence-based clinical management guidelines. This study aimed to determine the ROM and accuracy of FNAB in South Africa (SA).

METHODS

Thyroid specimens from 3 pathology laboratories registered between January 2015 and December 2019 were considered for inclusion. ROM was obtained per TBSRTC category by cytohistological correlation and dividing the total number of specimens with malignant histology by the total number of cases operated. Accuracy was calculated based on the Bethesda category and eventual malignant histology.

RESULTS

Seventeen thousand seven hundred and seventy-three histology and 4,791 cytology cases were identified. Of the 4,791 cytology cases, 931 (19%) underwent surgery. More than a third (333, 35.8%) of cases were confirmed as malignant following histological assessment, with the majority being benign (584, 62.7%). The ROM for the nondiagnostic and benign categories was 24.3% and 20.5%. The highest ROM was for category VI (91.5%), followed by categories V (69.5%), IV (51.9%), and III (38.8%). Thyroid FNAB had a sensitivity of 73%, specificity of 74%, and overall accuracy of 74%.

CONCLUSION

Bethesda categories II and IV have a relatively higher ROM in SA compared to findings from other developed countries. The diagnostic accuracy of thyroid FNAB in SA and the high rate of nondiagnostic diagnoses (38%) require further investigation. A national thyroid registry could provide location-specific data to aid the implementation of appropriate local policies and national guidelines for practicing thyroid surgeons.

Comparison of fine-needle aspiration with fine-needle capillary cytology in thyroid nodules

INTRODUCTION

High false-negative results have been reported for fine-needle aspiration (FNA) cytology in thyroid nodules. Fine-needle capillary (FNC) cytology is an alternative technique that prevents aspiration, reducing tissue damage. This study aimed to compare FNA and FNC in assessing thyroid nodules and in terms of their predictive role in the appropriate diagnosis of malignancy.

METHODS

This is a comparative prospective study conducted on 486 patients. FNA was performed in 235 patients during 2016 and 2017 and FNC in 251 patients during 2018 and 2019. The quality of cytological specimens was compared and then correlated with the final histopathological findings of 39 patients who underwent thyroidectomy.

RESULTS

Both groups were statistically similar regarding age and sex distribution. The FNA technique yielded significantly higher adequate specimens compared with FNC (p<0.001). Abundant blood in the background was found more frequently in the FNA technique (p<0.001). The sensitivity and specificity of FNA for malignancy diagnosis were both 100%, compared with 83.3% and 57.7% for FNC, respectively.

CONCLUSIONS

The two methods, FNA and FNC, did not differ in terms of overall quality. FNA was superior regarding consistency with the histopathological results and the ability to diagnose malignancy.

Galectin-3: One Molecule for an Alphabet of Diseases, from A to Z

Galectin-3 (Gal-3) regulates basic cellular functions such as cell-cell and cell-matrix interactions, growth, proliferation, differentiation, and inflammation. It is not surprising, therefore, that this protein is involved in the pathogenesis of many relevant human diseases, including cancer, fibrosis, chronic inflammation and scarring affecting many different tissues. The papers published in the literature have progressively increased in number during the last decades, testifying the great interest given to this protein by numerous researchers involved in many different clinical contexts. Considering the crucial role exerted by Gal-3 in many different clinical conditions, Gal-3 is emerging as a new diagnostic, prognostic biomarker and as a new promising therapeutic target. The current review aims to extensively examine the studies published so far on the role of Gal-3 in all the clinical conditions and diseases, listed in alphabetical order, where it was analyzed.

Integrated analysis of fine-needle-aspiration cystic fluid proteome, cancer cell secretome, and public transcriptome datasets for papillary thyroid cancer biomarker discovery

Thyroid ultrasound and ultrasound-guided fine-needle aspiration (USG/FNA) biopsy are currently used for diagnosing papillary thyroid carcinoma (PTC), but their detection limit could be improved by combining other biomarkers. To discover novel PTC biomarkers, we herein applied a GeLC-MS/MS strategy to analyze the proteome profiles of serum-abundant-protein-depleted FNA cystic fluid from benign and PTC patients, as well as two PTC cell line secretomes. From them, we identified 346, 488, and 2105 proteins, respectively. Comparative analysis revealed that 191 proteins were detected in the PTC but not the benign cystic fluid samples, and thus may represent potential PTC biomarkers. Among these proteins, 101 were detected in the PTC cell line secretomes, and seven of them (NPC2, CTSC, AGRN, GPNMB, DPP4, ERAP2, and SH3BGRL3) were reported in public PTC transcriptome datasets as having 4681 elevated mRNA expression in PTC. Immunoblot analysis confirmed the elevated expression levels of five proteins (NPC2, CTSC, GPNMB, DPP4, and ERAP2) in PTC versus benign cystic fluids. Immunohistochemical studies from near 100 pairs of PTC tissue and their adjacent non-tumor counterparts further showed that AGRN (n = 98), CTSC (n = 99), ERAP2 (n = 98) and GPNMB (n = 100) were significantly (p < 0.05) overexpressed in PTC and higher expression levels of AGRN and CTSC were also significantly associated with metastasis and poor prognosis of PTC patients. Collectively, our results indicate that an integrated analysis of FNA cystic fluid proteome, cancer cell secretome and tissue transcriptome datasets represents a useful strategy for efficiently discovering novel PTC biomarker candidates.

A tertiary center's experience with second review of 3885 thyroid cytopathology specimens

BACKGROUND

Although the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) has standardized the diagnostic terminology for thyroid fine-needle aspiration (FNA), morphological interpretation remains subjective, and interobserver discrepancies are expected. This study quantifies the frequency and magnitude of these discrepancies in a single tertiary center's experience and elucidates key factors that are associated with changes in diagnosis.

METHODS

Institutional consultation for 3885 thyroid cytological samples over 45 months were reviewed. BSRTC classification made by the sending institution was compared with that of our institution. An ANOVA was performed to determine factors that may be associated with interinstitutional diagnostic differences. Histopathology diagnoses were available for 1049 (27%) nodules; the malignancy rates for inside and outside BSRTC classifications were calculated.

RESULTS

There were 937 1-step changes and 301 ≥2-step diagnostic discrepancies comprising 24% and 8% of all cases, respectively. Second review decreased the indeterminate rate 38% to 28% (P < .000001). Indeterminate diagnostic category before second review, low specimen cellularity, Hashimoto's thyroiditis, and low volume of consults from the sending institution were associated with discordance. Of the 1049 thyroid nodules operated for which unequivocal histopathology was available, the malignancy rates for the BSRTC categories before and after second review were compared. Categorical upgrades were associated with a malignancy rate of 84%, whereas downgrades were associated with a malignancy rate of 38% (P < .000001).

CONCLUSION

This is the largest series to date of thyroid cytology second review. The BSRTC classification changed 32% of the time, potentially resulting in significant changes in clinical and surgical management. Because certain specimen characteristics (indeterminate diagnostic category before second review, low specimen cellularity, Hashimoto's thyroiditis, and low volume of consults from the sending institution) were particularly associated with a diagnosis change, morphological second review may be of potential benefit in these settings.

Does large needle aspiration biopsy add pain to the thyroid nodule evaluation?

Thyroid large needle aspiration biopsy is disregarded because it is thought to be associated with pain. This is in contrast with our 32 years long experience. We surveyed reports of pain in patients examined with fine needle aspiration biopsy (78, 87.2% women, mean age 59 years) or FNAB+large needle aspiration biopsy (48, 87.5% women, mean age 60 years). Each patient was questioned regarding a) no unpleasant sensation (score "0"); b) unpleasant sensation ("1"); c) mild pain (no analgesic used; "2"); or d) pain (analgesic used; "3"). The mean size of the needle used was for FNAB 22.3±0.7 or 20.8±1 gauge in the fine needle aspiration or fine needle aspiration plus large needle aspiration biopsy group, respectively (p<.0001). The number of percutaneous punctures was higher in the fine needle aspiration plus large needle aspiration biopsy group. However, the pain score in the fine needle aspiration biopsy or fine needle aspiration biopsy plus large needle aspiration biopsy group was not significantly different. Large needle aspiration biopsy after fine needle aspiration biopsy does not add any discomfort or pain and therefore in light of the demonstrable benefits, should be included in clinical algorithms for the evaluation of thyroid nodules.

Biotinidase is a novel marker for papillary thyroid cancer aggressiveness

Biotinidase was identified in secretome analysis of thyroid cancer cell lines using proteomics. The goal of the current study was to analyze the expression of biotinidase in thyroid cancer tissues and fine needle aspiration (FNA) samples to evaluate its diagnostic and prognostic potential in thyroid cancer. Immunohistochemical analysis of biotinidase was carried out in 129 papillary thyroid cancer (PTC, 34 benign thyroid tissues and 43 FNA samples and correlated with patients' prognosis. Overall biotinidase expression was decreased in PTC compared to benign nodules (p = 0.001). Comparison of aggressive and non-aggressive PTC showed decrease in overall biotinidase expression in the former (p = 0.001). Loss of overall biotinidase expression was associated with poor disease free survival (p = 0.019, Hazards ratio (HR) = 3.1). We examined the effect of subcellular compartmentalization of nuclear and cytoplasmic biotinidase on patient survival. Decreased nuclear expression of biotinidase was observed in PTC as compared to benign tissues (p<0.001). Upon stratification within PTC, nuclear expression was reduced in aggressive as compared to non-aggressive tumors (p<0.001). Kaplan-Meier survival analysis showed significant association of loss of nuclear biotinidase expression with reduced disease free survival (p = 0.014, HR = 5.4). Cytoplasmic biotinidase expression was reduced in aggressive thyroid cancers in comparison with non-aggressive tumors (p = 0.002, Odds ratio (OR) = 0.29) which was evident by its significant association with advanced T stage (p = 0.003, OR = 0.28), nodal metastasis (p<0.001, OR = 0.16), advanced TNM stage (p<0.001, OR = 0.21) and extrathyroidal extension (p = 0.001, OR = 0.23). However, in multivariate analysis extrathyroidal extension emerged as the most significant prognostic marker for aggressive thyroid carcinomas (p = 0.015, HR = 12.8). In conclusion, loss of overall biotinidase expression is a novel marker for thyroid cancer aggressiveness.

Large needle aspiration biopsy histology for preoperative selection of Hürthle cell thyroid nodules

AIMS

To assess whether the large needle aspiration biopsy (LNAB) histological distinction between pure microfollicular nodules and mixed micro-macrofollicular nodules can assist preoperative selection of a Hürthle cell nodule (HCN) discovered by fine needle aspiration cytology (FNAC).

METHODS AND RESULTS

In 24 HCN identified by preoperative FNAC, preoperative LNAB histology was compared with postoperative pathology. FNAC demonstrated seven benign HCN (negative), eight HCN with atypia (positive); seven suspected cancers with HC (positive); and two cancers with Hürthle cells (positive). LNAB showed mixed micro-macrofollicular hyperplastic features in 12 nodules (negative) and a microfollicular structure in 12 nodules (positive), two of which included findings of papillary cancer. Postoperative findings were benign (negative) in 16 patients and malignant (positive) in eight patients. The sensitivity and specificity for FNAC were 87.5% [seven of eight, 95% confidence interval (CI): 47.3-99.7%) and 37.5% (six of 16, 95% CI: 15.2-64.6%], respectively, and for LNAB were 87.5% (seven of eight, 95% CI: 47.3-99.7%) and 68.8% (11 of 16, 95% CI: 41.3-89.0%), respectively. FNAC results were significantly different from postoperative results (McNemar's test, exact two-sided P=0.012), while LNAB results were not (McNemar's test, exact two-sided P=0.219).

CONCLUSIONS

These data suggest that LNAB histology is more accurate than FNAC cytology for the preoperative selection of HCN.

Secretome-based identification and characterization of potential biomarkers in thyroid cancer

In search of thyroid cancer biomarkers, proteins secreted by thyroid cancer cell lines, papillary-derived TPC-1 and anaplastic-derived CAL62, were analyzed using liquid chromatography-tandem mass spectrometry. Of 46 high-confidence identifications, 6 proteins were considered for verification in thyroid cancer patients' tissue and blood. The localization of two proteins, nucleolin and prothymosin-α (PTMA), was confirmed in TPC-1 and CAL62 cells by confocal microscopy and immunohistochemically in xenografts of TPC-1 cells in NOD/SCID/γ mice and human thyroid cancers (48 tissues). Increased nuclear and cytoplasmic expression of PTMA was observed in anaplastic compared to papillary and poorly differentiated carcinomas. Nuclear expression of nucleolin was observed in all subtypes of thyroid carcinomas, along with faint cytoplasmic expression in anaplastic cancers. Importantly, PTMA, nucleolin, clusterin, cysteine-rich angiogenic inducer 61, enolase 1, and biotinidase were detected in thyroid cancer patients' sera, warranting future analysis to confirm their potential as blood-based thyroid cancer markers. In conclusion, we demonstrated the potential of secretome analysis of thyroid cancer cell lines to identify novel proteins that can be independently verified in cell lines, xenografts, tumor tissues, and blood samples of thyroid cancer patients. These observations support their potential utility as minimally invasive biomarkers for thyroid carcinomas and their application in management of these diseases upon future validation.

Intraoperative detection of thyroid carcinoma by fourier transform infrared spectrometry

BACKGROUND

Fourier transform infrared (FTIR) spectroscopy is a powerful tool for distinguishing cancerous tissue from normal one. Our aim in this study was to establish tissue discriminant analysis for thyroid malignancy and benign samples intraoperatively using FTIR spectroscopy.

METHODS

Seventeen papillary thyroid cancer and 43 nodular goiter tissues were obtained and underwent FTIR spectroscopy scanning intraoperatively. Nine peak positions were identified and assigned. Peak position values and wave intensity ratios were measured in every single spectrum. Data of malignant and benign groups were compared and equations of canonical discriminant analysis were established.

RESULTS

Peak positions of P1640, P1240, P1550, and peak intensity ratios of I3375/I1460, I1640/I1460, I1400/I1460, I1550/I1080, I1080/I1460, and I1640/I1550 of thyroid papillary carcinoma group are significantly different from nodular goiter group. The sensitivity, specificity, and accuracy rate of the discriminants are 83.3%, 95.2%, and 91.67%, respectively.

CONCLUSION

FTIR spectroscopy technique in combination with canonical discriminant analysis method can achieve fast and accurate discrimination for malignant and benign thyroid nodules during operation.

Ultrasound-guided fine-needle aspiration of thyroid nodules: stratification of malignancy risk using follicular proliferation grading, clinical and ultrasonographic features

OBJECTIVE

To evaluate the diagnostic value of fine-needle aspiration (FNA) cytology and the additive contribution brought by clinical and ultrasound (US) features.

METHOD

Cytological and histological diagnoses were compared in a series of 924 patients who underwent US-guided FNA before surgery. We additionally developed a grading system for follicular proliferation (FP) FNA diagnosis, and investigated its impact on the malignancy risk as well as the additive contribution of clinical and US features by means of decision tree analysis.

RESULTS

Excluding FP cases (n=395), our data demonstrated that strictly benign or malignant FNA diagnoses exhibit great concordance with benign or malignant histological diagnoses (97.8% accuracy). Our grading system that was applied to the 395 FP cases revealed that grades 1, 2 and 3 were associated with a 7.7, 17.7 and 45.7% incidence of malignancy respectively. Decision tree analysis resulted in a classification model which involved FP grade, patient's age, serum thyroglobulin level, nodule size and nodule uniqueness. This model identified a subgroup of patients with grade 1 FP nodules who were older than 50 years, and who had a higher risk of malignancy (17.9%). In addition, high serum thyroglobulin levels were associated with a very high malignancy risk (75.0%) for patients with grade 3 FP nodules. Finally, among grade 2 FP patients, unique and large nodules were associated with a high malignancy risk of 36.1%.

CONCLUSIONS

The integration of FP grade, clinical and US features allows the stratification of patients with FP cytology according to their risk of malignancy.

Galectin-3 detection on large-needle aspiration biopsy improves preoperative selection of thyroid nodules: a prospective cohort study

BACKGROUND

New techniques of improving diagnostic reliability of thyroid nodules are needed.

AIM AND METHODS

This prospective cohort study includes patients with one (201) or multiple (22) palpable nodule(s). Preoperative fine-needle aspiration biopsy (FNAB), large-needle aspiration biopsy (LNAB), and galectin-3 detection on LNAB (GAL-3-LNAB) (total of 245 nodules) were compared when the FNAB finding was 'inadequate' or 'indeterminate'. The sizes of the needles used for FNAB and LNAB were compared with the size of thyroid follicles. Forty nodules were surgically excised according to current recommendation.

RESULTS

GAL-3-LNAB was inadequate in 4% of nodules, compared with 34% using FNAB and 11% using LNAB (P < 0.0001). GAL-3-LNAB showed no indeterminate findings, compared with 15% using FNAB and 13% using LNAB (P < 0.0001). Among the 40 excised nodules, GAL-3-LNAB showed the highest accuracy values. The sensitivity (P = 0.011) and specificity (P < 0.000; P = 0.001) ranges were 40%-100% and 20%-40% for FNAB, 40%-100% and 50%-53.7% for LNAB, and 100% and 76.7%-80% for GAL-3-LNAB, respectively. The largest needles used for LNAB, 20 or 18 gauge, with an internal diameter of 0.6 or 0.91 mm, recorded the lowest rate of inadequate or indeterminate FNAB findings.

CONCLUSIONS

GAL-3-LNAB reduced inadequate, abolished indeterminate findings, and provided specificity values higher than FNAB or LNAB in palpable thyroid nodules.

Development of a clinical decision model for thyroid nodules

Background

Thyroid nodules represent a common problem brought to medical attention. Four to seven percent of the United States adult population (10–18 million people) has a palpable thyroid nodule, however the majority (>95%) of thyroid nodules are benign. While, fine needle aspiration remains the most cost effective and accurate diagnostic tool for thyroid nodules in current practice, over 20% of patients undergoing FNA of a thyroid nodule have indeterminate cytology (follicular neoplasm) with associated malignancy risk prevalence of 20–30%. These patients require thyroid lobectomy/isthmusectomy purely for the purpose of attaining a definitive diagnosis. Given that the majority (70–80%) of these patients have benign surgical pathology, thyroidectomy in these patients is conducted principally with diagnostic intent. Clinical models predictive of malignancy risk are needed to support treatment decisions in patients with thyroid nodules in order to reduce morbidity associated with unnecessary diagnostic surgery.

Methods

Data were analyzed from a completed prospective cohort trial conducted over a 4-year period involving 216 patients with thyroid nodules undergoing ultrasound (US), electrical impedance scanning (EIS) and fine needle aspiration cytology (FNA) prior to thyroidectomy. A Bayesian model was designed to predict malignancy in thyroid nodules based on multivariate dependence relationships between independent covariates. Ten-fold cross-validation was performed to estimate classifier error wherein the data set was randomized into ten separate and unique train and test sets consisting of a training set (90% of records) and a test set (10% of records). A receiver-operating-characteristics (ROC) curve of these predictions and area under the curve (AUC) were calculated to determine model robustness for predicting malignancy in thyroid nodules.

Results

Thyroid nodule size, FNA cytology, US and EIS characteristics were highly predictive of malignancy. Cross validation of the model created with Bayesian Network Analysis effectively predicted malignancy [AUC = 0.88 (95%CI: 0.82–0.94)] in thyroid nodules. The positive and negative predictive values of the model are 83% (95%CI: 76%–91%) and 79% (95%CI: 72%–86%), respectively.

Conclusion

An integrated predictive decision model using Bayesian inference incorporating readily obtainable thyroid nodule measures is clinically relevant, as it effectively predicts malignancy in thyroid nodules. This model warrants further validation testing in prospective clinical trials.