Errors in thyroid gland fine-needle aspiration

Impact of Ultrasonographic Features for Thyroid Malignancy in Patients With Bethesda Categories III, IV, and V: A Retrospective Observational Study in a Tertiary Center

Introduction: Although fine-needle aspiration biopsy (FNAB) with cytologic interpretation using the Bethesda System for Reporting Thyroid Cytopathology has been widely used for thyroid nodules, its efficiency in Bethesda categories of III, IV, and V has been questioned due to variable risk of malignancy. We aimed to evaluate the impact of radiological parameters in Bethesda category III, IV, and V for thyroid malignancy.

Methods: We performed a retrospective review of patients with Bethesda category III, IV, and V, and subsequent thyroidectomy. Demographic, ultrasonographic, and clinical variables were recorded. Independent variables for thyroid malignancy and the predictive power of imaging findings were analyzed.

Results: There were 159 patients with a mean age of 48.1±13.4 years. Hypoechogenicity of the index nodule was the most common finding in 87 patients (54.7%). There were 74 (46.5%), 34 (21.4%), and 51 patients (32.1%) with Bethesda III, IV, and V categories, respectively. There were 91 patients (57.2%) with a diagnosis of thyroid malignancy. Overall malignant pathology was detected in 18 (24.3%), 25 (73.5%), and 48 patients (94.1%) in Bethesda III, IV, and V categories, respectively (p=0.001). The presence of solitary nodule, hypoechogenicity, and solid structure of index nodule and Bethesda category IV and V were significant variables for final malignant pathology (p<0.05 for all).

Conclusion: Hypoechogenicity and solid structure in a solitary index nodule should be regarded as significant ultrasonographic findings for thyroid malignancy. Bethesda category IV and V were also significantly associated with malignancy.

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC): A report of 2,781 cases in a Chinese population

Objective

To evaluate the diagnostic utility of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) at Peking University Cancer Hospital, the incidence of noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), and the impact of reclassification on cytopathological outcomes.

Methods

We performed a retrospective study of thyroid fine-needle aspiration (FNA) cases between April 2014 and March 2019. The FNA results were classified according to TBSRTC. Post-surgery histological findings were followed up.

Results

A total of 2,781 thyroid FNAs were performed. The incidences of the 6 diagnostic categories (DCs I-VI) were 14.8%, 17.1%, 15.8%, 2.3%, 11.6% and 38.5%, respectively. A total of 1,122 patients (40.3%) had corresponding histological results. NIFTP accounted for 0.4% of papillary thyroid carcinoma (PTC) cases, and there was no significant difference in the risk of malignancy (ROM) for each TBSRTC DC between "NIFTP=carcinoma (Ca)" and "NIFTP≠Ca". When "NIFTP=Ca", the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of TBSRTC were 98.0%, 84.0%, 99.4%, 58.3%, and 97.5%, respectively. When "NIFTP≠Ca", the sensitivity, specificity, PPV, NPV and accuracy of the TBSRTC were 98.1%, 81.5%, 99.3%, 61.1%, and 97.5%, respectively.

Conclusions

TBSRTC is effective in the preoperative diagnosis of thyroid nodules in Peking University Cancer Hospital. The impact of the reclassification of NIFTP on cytopathological outcomes is limited because of its low incidence, and the revised ROMs are not suitable for Asian patients.

Core needle biopsy in the management of thyroid nodules with an indeterminate fine-needle aspiration report

Ultrasonography (US)-guided fine-needle aspiration biopsy (FNAB) cytology is widely used but is limited due to its pathologically indeterminate results in diagnosing thyroid nodules. Recently, US-guided core-needle biopsy (CNB) was introduced as an effective and safe technique for diagnosing indeterminate thyroid nodules. Using CNB, information about architectural histologic structure such as nodule capsule or more immunochemical staining can be obtained which lead to a more accurate diagnosis. Up to 98% of indeterminate thyroid lesions can be classified as malignant or benign when CNB is used for follow-up analysis. Other evidences revealed the effectiveness of CNB in reducing inconclusive results and improving the diagnostic performance of thyroid nodules initially diagnosed as AUS/FLUS by FNAB. In this review, we investigate how to deal with indeterminate thyroid nodules diagnosed by FNAB and determine how CNB has a role in diagnosing these indeterminate thyroid nodules.

The Value of Negative Diagnosis in Thyroid Fine-Needle Aspiration: a Retrospective Study with Histologic Follow-Up

The Bethesda System for reporting thyroid cytopathology (BSRTC) predicts an incidence of malignancy of less than 5% in thyroid nodules with a benign diagnosis on fine-needle aspiration (FNA). However, recent series have suggested that the true rate of malignancy might be significantly higher in this category of patients. We reviewed our experience by performing a retrospective analysis of patients with benign thyroid FNA results who underwent thyroidectomy between 2008 and 2013 at a large academic center. Information including demographics, ultrasound features, FNA diagnosis, and surgical follow-up information were recorded. Slides were reviewed on cytology-histology discrepant cases, and it was determined whether the discrepancy was due to sampling or interpretation error. A total of 802 FNA cases with a benign diagnosis and surgical follow-up were identified. FNA diagnoses included 738 cases of benign goiter and 64 cases of lymphocytic thyroiditis. On subsequent surgical resection, 144 cases were found to be neoplastic, including 117 malignant cases. False negative, defined as interpretation error and inadequate biopsy of the nodule harboring malignancy, was 6%. When cases of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) were excluded from the analysis, false-negative rate was 5%. When microPTC cases were excluded, false-negative rate was 3% and was slightly less than 3% when both microPTC and NIFTP cases were excluded from the analysis. Retrospective review of neoplastic cases showed that 57% were due to sampling error and 43% were due to interpretation error. Interpretation error was more likely to occur in follicular patterned neoplasms (75%), while sampling error was more common in non-follicular variants of papillary thyroid carcinoma (non-FVPTC) (61%). With the exclusion of microPTC, interpretation errors were still more likely to occur in follicular neoplasms (79%) but there was no significant difference in sampling error between non-FVPTC (37%) and follicular patterned neoplasms (42%). Tumor size was larger in cases with interpretation error (mean = 2.3 cm) compared to cases with sampling error (mean = 1.4 cm). This study shows that the false-negative rate of thyroid FNA at our institution is not significantly above the rate suggested by the BSRTC. Interpretation errors were more likely to occur in follicular patterned neoplasms, while non-FVPTC was more frequently found in false negative cases due to inadequate sampling.

Broadband (550-1350 nm) diffuse optical characterization of thyroid chromophores

Thyroid plays an important role in the endocrine system of the human body. Its characterization by diffuse optics can open new path ways in the non-invasive diagnosis of thyroid pathologies. Yet, the absorption spectra of tyrosine and thyroglobulin–key tissue constituents specific to the thyroid organ–in the visible to near infrared range are not fully available. Here, we present the optical characterization of tyrosine (powder), thyroglobulin (granular form) and iodine (aqueous solution) using a time domain broadband diffuse optical spectrometer in the 550–1350 nm range. Various systematic errors caused by physics of photo migration and sample inherent properties were effectively suppressed by means of advanced time domain diffuse optical methods. A brief comparison with various other known tissue constituents is presented, which reveals key spectral regions for the quantification of the thyroid absorbers in an in vivo scenario.

The role of core needle biopsy in the diagnosis of initially detected thyroid nodules: a systematic review and meta-analysis

OBJECTIVES

To systematically review the published literature and evaluate the efficacy and safety of core needle biopsy (CNB) for initially detected thyroid nodules.

METHODS

The Ovid-MEDLINE and Embase databases were searched for studies evaluating CNB for the diagnosis of initially detected thyroid nodules. A meta-analysis was performed to evaluate non-diagnostic results, inconclusive results and diagnostic accuracy for a diagnosis of malignancy with CNB. To overcome heterogeneity, multiple subgroup analyses were performed. The complication rate was also evaluated.

RESULTS

Thirteen eligible studies, which included a total sample size of 9,166 patients with 13,585 nodules, were included. The pooled proportions were 3.5% (95% CI 2.4-5.1) for non-diagnostic results and 13.8% (95% CI 9.1-20.3) for inconclusive results. Considerable heterogeneity was observed among the studies in terms of the pooled proportions for CNB (I²=92.9%, 97%). With regard to the diagnostic performance for malignancy, the sensitivity was 80% (95% CI 75-85) and the specificity was 100% (95% CI 93-100). Only two major complications of CNB were observed.

CONCLUSIONS

CNB demonstrates a low non-diagnostic result rate and high diagnostic accuracy for initially detected thyroid nodules and a low major complication rate. These findings indicate that CNB may be a feasible diagnostic tool for patients with initially detected thyroid nodules.

KEY POINTS

CNB demonstrates high diagnostic accuracy for initially detected thyroid nodules. CNB demonstrates a low major complication rate. CNB may be a feasible diagnostic tool for patients with initially detected thyroid nodules.

Shear wave elastography combined with the thyroid imaging reporting and data system for malignancy risk stratification in thyroid nodules

To retrospectively evaluate the diagnostic performance of shear wave elastography (SWE) and thyroid imaging reporting and data system (TI-RADS) in differentiating malignant and benign thyroid nodules. A total of 313 thyroid nodules in 227 patients were included. All thyroid nodules were underwent SWE and TI-RADS before fine needle aspiration biopsy and/or surgery. SWE elasticity indices of the maximum (Emax), mean (Emean), minimum (Emin) and elastic ratio (ER) in thyroid nodules were measured. Nodules with solid component, marked hypoechogenicity, poorly defined margins, micro-calcifications, and a taller-than-wide shape were classified as suspicious at gray-scale ultrasonography. The level of TI-RADS was determined according to the number of suspicious ultrasonography features. The combined methods of SWE and TI-RADS in thyroid nodules were calculated. In the 313 nodules, 194 were malignant, and 119 were benign. SWE and TI-RADS were significantly higher in malignant nodules than benign nodules (P < 0.001). The most accurate SWE cut-off value, 51.95 kPa for Emax, achieved a sensitivity of 81.44% and a specificity of 83.19% for discriminating malignant nodules from benign nodules. There are two methods in combination with SWE and TI-RADS. The one is "tandem" method, which has a higher specificity (95.80%), positive likelihood ratio (18.16) and positive predictive value (96.73%). The other one is "parallel" method, which shows sensitivity (94.85%), negative likelihood ratio (0.07) and negative predictive value (90.00%).We believe that the methods could be used as a simple tool to stratify the risk of thyroid nodules accurately.

Detection and Identification of Serum Peptides Biomarker in Papillary Thyroid Cancer

Background

Papillary thyroid cancer (PTC) is currently the most commonly diagnosed endocrine malignancy. In addition, the sex- and age-adjusted incidence of PTC has exhibited a greater increase over the last 2 decades than in many other malignancies. Thus, discovering noninvasive specific serum biomarker to distinguish PTC from cancer-free controls in its early stages remains an important goal.

Material/Methods

Serum samples from 88 PTC patients and 80 cancer-free controls were randomly allocated into training or validation sets. Serum peptide profiling was performed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) after using weak cation exchange magnetic beads (WCX-MB), and the results were evaluated by use of ClinProTools™ Software. To distinguish PTC from cancer-free controls, quick classifier (QC), supervised neural network (SNN), and genetic algorithm (GA) models were established. The models were blindly validated to verify their diagnostic capabilities. The most discriminative peaks were subsequently identified with a nano-liquid chromatography-electrospray ionization-tandem mass spectrometry system.

Results

Six peptide ions were identified as the most discriminative peaks between the PTC and cancer-free control samples. The QC model exhibited satisfactory sensitivity and specificity among the 3 models that were validated. Two peaks, at m/z 2671.17 and m/z 1464.68, were identified as fragments of the alpha chain of fibrinogen, while a peak at m/z 1738.92 was a fragment of complement component 4A/B.

Conclusions

MS combined with ClinProTools™ software was able to detect peptide biomarkers in PTC patients. In addition, the constructed classification models provided a serum peptidome pattern for distinguishing PTC from cancer-free controls. Both fibrinogen α and complement C4A/B were identified as potential markers for diagnosis of PTC.

The diagnostic ability of core needle biopsy in nodular thyroid disease

INTRODUCTION Non-diagnostic results of fine needle aspiration biopsy (FNAB) remain an important limitation of this technqiue. The aim of our study was to evaluate the results of core needle biopsy (CNB) of thyroid nodules and its effectiveness in non-diagnostic FNAB cases. METHODS CNBs were performed in 1,000 patients (154 male, 846 female; mean age: 50.2 years, range: 18-86 years) with a spring loaded 20G needle. Of these, 143 had initially had FNABs that were insufficient for evaluation. The CNB reports were reviewed. Patients with suspicious or malignant CNB results underwent total thyroidectomy. RESULTS When considering all 1,000 CNBs, the non-diagnostic rate was 1.5% (15/1,000). However, when the first 100 cases were eliminated as a learning curve, this reduced to 0.9% (8/900). Of the 143 cases with initial FNABs that were non-diagnostic, 0.7% (1/143) were also non-diagnostic on CNB. Twelve patients underwent surgery because of malignant CNB reports and all of these cases were confirmed as malignant by the postoperative pathology specimen results (100% accuracy). There were no major complications although three self-limiting minor complications were observed. CONCLUSIONS CNB is a safe and accurate method. It is more diagnostic than FNAB for nodular thyroid disease.

First-Line Use of Core Needle Biopsy for High-Yield Preliminary Diagnosis of Thyroid Nodules

BACKGROUND AND PURPOSE

Although core needle biopsy was introduced as a diagnostic alternative to fine-needle aspiration, the utility and safety of core needle biopsy for thyroid nodules in a large population has yet to be studied comprehensively. We evaluate core needle biopsy yields on a large-scale basis to investigate its potential in the preliminary diagnosis of thyroid nodules.

MATERIALS AND METHODS

Between March 2005 and December 2013, 2448 initially detected thyroid nodules from 2120 consecutive patients who underwent core needle biopsy were retrospectively evaluated. Of these, 72 thyroid nodules from 63 patients were excluded due to prior fine-needle aspiration attempts. The inconclusive and conclusive result rates, diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and unnecessary surgery rate of core needle biopsy were evaluated.

RESULTS

With core needle biopsy as the first-line method, the inconclusive result rate was 11.9% (283/2376) and the conclusive result rate was 88.1% (2093/2376). The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of core needle biopsy for the diagnosis of malignancy were 96.7% (1160/1200), 89.7% (347/387), 100% (813/813), 100% (347/347), and 95.3% (813/853), respectively. There were no major complications and 12 minor complications.

CONCLUSIONS

We have demonstrated that first-line use of core needle biopsy may well improve diagnostic accuracy in thyroid nodules, reducing inconclusive or false-negative results and unnecessary operations. Such benefits underscore the promising role of core needle biopsy in managing thyroid nodules and optimizing related surgical decision-making.

Comparison of diagnostic yield of core-needle and fine-needle aspiration biopsies of thyroid lesions: Systematic review and meta-analysis

Objectives

Thyroid nodular disease is one of the most commonly observed medical conditions. Cytological evaluation of the specimens obtained with fine-needle aspiration biopsy (FNAB) is the most accurate tool for selecting nodules which should be further surgically removed. A major limitation of this method is the high occurrence of non-diagnostic results. This indicates the need for improvement of the thyroid biopsy technique. The aim of this meta-analysis was to compare the diagnostic value of thyroid core-needle biopsies (CNBs) and FNABs.

Materials and methods

PubMed/MEDLINE, Cochrane Library, Scopus, Cinahl, Academic Search Complete, Web of Knowledge, PubMed Central, PubMed Central Canada and Clinical Key databases were searched. Risk ratios (RRs) of non-diagnostic results were meta-analysed using the random-effects model.

Results

Eleven studies were included in the quantitative analysis. CNB yielded significantly more diagnostic results – the pooled risk ratio (RR) of gaining a non-diagnostic result was 0.27 (p<0.0001). For lesions with one previous non-diagnostic FNAB, RR was 0.22 (p<0.0001).

Conclusions

CNB seems to be a valuable diagnostic technique yielding a higher proportion of diagnostic results than conventional FNAB. It is also significantly more effective in case of nodules with a prior non-diagnostic result of FNAB results than repeated FNABs.

Key Points

• Core-needle biopsy yields a higher proportion of diagnostic results than fine-needle biopsy.

• Core-needle biopsies may decrease the amount of unnecessary thyroidectomies.

• Probability of gaining non-diagnostic result using core-needle biopsy is almost four times lower.

Focal Lymphocytic Thyroiditis Nodules Share the Features of Papillary Thyroid Cancer on Ultrasound

PURPOSE

It is often difficult to discriminate focal lymphocytic thyroiditis (FLT) or adenomatous hyperplasia (AH) from thyroid cancer if they both have suspicious ultrasound (US) findings. We aimed to make a predictive model of FLT from papillary thyroid cancer (PTC) in suspicious nodules with benign cytologic results.

MATERIALS AND METHODS

We evaluated 214 patients who had undergone fine-needle aspiration biopsy (FNAB) and had shown thyroid nodules with suspicious US features. PTC was confirmed by surgical pathology. FLT and AH were confirmed through more than two separate FNABs. Clinical and biochemical findings, as well as US features, were evaluated.

RESULTS

Of 214 patients, 100 patients were diagnosed with PTC, 55 patients with FLT, and 59 patients with AH. The proportion of elevated thyrotropin (TSH) levels (p=0.014) and thyroglobulin antibody (Tg-Ab) or thyroid peroxidase antibody (TPO-Ab) positivity (p<0.001) in the FLT group was significantly higher than that in the PTC group. Regarding US features, absence of calcification (p=0.006) and "diffuse thyroid disease" (DTD) pattern on US (p<0.001) were frequently seen in the FLT group. On multivariate analysis, Tg-Ab positivity, presence of a DTD pattern on US, and absence of calcification in nodules were associated with FLT with the best specificity of 99% and positive predictive value of 96%. In contrast, a taller than wide shape of nodules was the only variable significant for differentiating AH from PTC.

CONCLUSION

Suspicious thyroid nodules with cytologic benign results could be followed up with US rather than repeat FNAB, if patients exhibit Tg-Ab positivity, no calcifications in nodules, and a DTD pattern on US.

Clinical audit of repeat fine needle aspiration in a general cytopathology service

Background:

The few studies on repeat aspiration focussed on accuracy of diagnosis following repeat. Numbers and documented reasons for repeat remain unaddressed.

Aim:

To study factors associated with requests for repeat fine needle aspiration cytology (FNAC).

Settings and Design:

Metropolitan hospital, clinical audit.

Materials and Methods:

Audit of 5104 FNAC in 10 months.

Statistical Analysis Used:

Univariate, and multivariate binary logistic regression.

Results:

Seven hundred and six patients (13.8%) were advised repeat aspirates. Three hundred and twelve of these were actually repeated (44.1%). Carryover of actually repeated aspirates to subsequent months averaged 10.8 (34.2%). Maximum numbers of repeat requests were from thyroid 76/415 (18.3%), followed by lymph node 310/1856 (16.7%), and from breast 86/716 (12.0%). Outcome of actually repeated aspirates were: Diagnostic 181/312 (58.0%), and non-diagnostic 131/312 (41.9%). Reasons for repeat were inadequate aspirates 370/706 (52.4%), non-diagnostic descriptive reports 309/706 (43.7%); in 27/706 (3.8%), no reason was mentioned.

Conclusions:

Inadequate aspirates, non-diagnostic descriptive reports, and FNAC/FNAB from thyroid, lymph nodes, and breast contribute to repeats. We suggest steps to reduce the number of repeat aspirates to eliminate extra work.

Imaging-cytology correlation of thyroid nodules with initially benign cytology

Objective. To determine the role of imaging-cytology correlation in reducing false negative results of fine-needle aspiration (FNA) at thyroid nodules. Methods. This retrospective study included 667 nodules 1 cm or larger in 649 patients diagnosed as benign at initial cytologic evaluation and that underwent follow-up ultrasound (US) or FNA following a radiologist's opinion on concordance between imaging and cytologic results. We compared the risk of malignancy of nodules classified into subgroups according to the initial US features and imaging-cytology correlation. Results. Among included nodules, 11 nodules were proven to be malignant (1.6%) in follow-up FNA or surgery. The malignancy rate was higher in nodules with suspicious US features (11.4%) than in nodules without suspicious US features (0.5%, P < 0.001). When a thyroid nodule had discordant US findings on image review after having benign FNA results, malignancy rate increased to 23.3%, significantly higher than that of nodules with suspicious US features (P < 0.001). However, no significant difference was found in the risk of malignancy between the nodules without suspicious US features (0.5%) and imaging-cytology concordant nodules (0.6%, P = 0.438). Conclusions. Repeat FNA can be effectively limited to patients with cytologically benign thyroid nodules showing discordance in imaging-cytology correlation after initial biopsy, which reduces unnecessary repeat aspirations.

Comparison of metabolic ratios of urinary estrogens between benign and malignant thyroid tumors in postmenopausal women

Background

Estrogen metabolism may be associated with the pathophysiological development of papillary thyroid carcinoma (PTC).

Methods

To evaluate the differential estrogen metabolism between benign and malignant PTCs, estrogen profiling by gas chromatography–mass spectrometry was applied to urine samples from postmenopausal patients with 9 benign tumors and 18 malignant stage I and III/IV PTCs.

Results

The urinary concentration of 2-methoxyestradiol was significantly lower in the stage I malignant patients (3.5-fold; P < 0.025) than in the benign group. The metabolic ratios of 16α-OH-estrone/estrone and estriol/estradiol, which are responsible for 16α-hydroxylase activity, were increased more than 2.5-fold in the advanced-stage malignant PTC (P < 0.02 each). The more than 6.2-fold decrease in the urinary 2-/16α-hydroxylase ratio in stage III/IV malignant PTC was consistent with the ratio in postmenopausal patients with endocrine gland cancers. In addition, reductive 17β-hydroxysteroid dehydrogenase (17β-HSD; estradiol/estrone or estriol/16α-OH-estrone) was present at significantly higher levels in subjects with stage III/IV malignant PTCs than in benign subjects (>3.5-fold difference; P < 0.002). In particular, the estriol/16α-OH-estrone ratio differentiated between the benign and early-stage malignant patients (P < 0.01).

Conclusions

Increased 16α-hydroxylation and/or a decreased 2-/16α-ratio, as well increased reductive 17β-HSD, with regard to estrogen metabolism could provide potential biomarkers. The devised profiles could be useful for differentiating malignant thyroid carcinomas from benign adenomas in postmenopausal women.

Malignancy risk assessment in patients with thyroid nodules using classification and regression trees

Purpose. We sought to investigate the utility of classification and regression trees (CART) classifier to differentiate benign from malignant nodules in patients referred for thyroid surgery. Methods. Clinical and demographic data of 271 patients referred to the Sadoughi Hospital during 2006–2011 were collected. In a two-step approach, a CART classifier was employed to differentiate patients with a high versus low risk of thyroid malignancy. The first step served as the screening procedure and was tailored to produce as few false negatives as possible. The second step identified those with the lowest risk of malignancy, chosen from a high risk population. Sensitivity, specificity, positive and negative predictive values (PPV and NPV) of the optimal tree were calculated. Results. In the first step, age, sex, and nodule size contributed to the optimal tree. Ultrasonographic features were employed in the second step with hypoechogenicity and/or microcalcifications yielding the highest discriminatory ability. The combined tree produced a sensitivity and specificity of 80.0% (95% CI: 29.9–98.9) and 94.1% (95% CI: 78.9–99.0), respectively. NPV and PPV were 66.7% (41.1–85.6) and 97.0% (82.5–99.8), respectively. Conclusion. CART classifier reliably identifies patients with a low risk of malignancy who can avoid unnecessary surgery.

The bethesda system for reporting thyroid cytopathology: a five-year retrospective review of one center experience

Fine-needle aspiration (FNA) of the thyroid gland is a widely accepted and accurate method for triaging patients with thyroid nodules. Thyroid FNA suffers from a reporting confusion due to multiplicity of category terminologies. To address this, The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) was recently introduced for unifying the terminology and morphologic criteria along with the corresponding risk of malignancy.

OBJECTIVE

The aim of this study was to report the diagnostic utility of TBSRTC at our institution and report the malignancy risk for FNA of thyroid lesions among Saudi patients using this system at KAUH (King Abdulaziz University Hospital), Jeddah, Saudi Arabia.

MATERIALS AND METHODS

A retrospective study identifying 250 thyroid FNAs performed among Saudi patients between Jan 2005-Dec 2010 was undertaken. Cytology specimen data was collected through a computerized search of our cytopathology archives.

RESULTS

Among the 250 thyroid FNAs, 84 were followed by surgical resection. The overall surgical yield of malignancy was 23.8%. The malignancy rate for the 6 categories was as follows: non diagnostic: 20%, benign: 3.1%, atypia of undetermined significance: 50%, suspicious for follicular neoplasm: 20%, suspicious for malignancy: 80%, malignant: 100%.

CONCLUSION

Retrospective classification of FNAs of thyroid lesions among Saudi patients using TBSRTC at KAAUH, Jeddah, Saudi Arabia, validates the diagnostic reproducibility of this system and yields similar results for risk of malignancy as reported by others. However the associated rates found for non diagnostic (20%) raise the possibility of malignancy risk in this category and validate the past observations that sample inadequacy is a common cause of false negative thyroid FNAs.

In vivo thyroid vibro-acoustography: a pilot study

Background

The purpose of this study was to evaluate the utility of a noninvasive ultrasound-based method, vibro-acoustography (VA), for thyroid imaging and determine the feasibility and challenges of VA in detecting nodules in thyroid.

Methods

Our study included two parts. First, in an in vitro study, experiments were conducted on a number of excised thyroid specimens randomly taken from autopsy. Three types of images were acquired from most of the specimens: X-ray, B-mode ultrasound, and vibro-acoustography. The second and main part of the study includes results from performing VA and B-mode ultrasound imaging on 24 human subjects with thyroid nodules. The results were evaluated and compared qualitatively.

Results

In vitro vibro-acoustography images displayed soft tissue structures, microcalcifications, cysts and nodules with high contrast and no speckle. In this group, all of US proven nodules and all of X-ray proven calcifications of thyroid tissues were detected by VA. In vivo results showed 100% of US proven calcifications and 91% of the US detected nodules were identified by VA, however, some artifacts were present in some cases.

Conclusions

In vitro and in vivo VA images show promising results for delineating the detailed structure of the thyroid, finding nodules and in particular calcifications with greater clarity compare to US. Our findings suggest that, with further development, VA may be a suitable imaging modality for clinical thyroid imaging.

Diagnostic accuracy of fine-needle aspiration versus core-needle biopsy for the diagnosis of thyroid malignancy in a clinical cohort

OBJECTIVES

To retrospectively compare the accuracy of fine-needle aspiration (FNA) and core-needle biopsy (CNB) for the diagnosis of thyroid malignancy

METHODS

We evaluated the results of FNA and CNB in 555 consecutive thyroid nodules with final diagnoses (malignancy 318, benign 237). All patients underwent FNA and CNB simultaneously for each nodule. We assessed the sensitivity, specificity and accuracy of FNA, CNB and FNA/CNB for the diagnosis of thyroid malignancy.

RESULTS

The sensitivity of FNA, CNB and FNA/CNB for thyroid malignancy was 68.6%, 86.8% and 90.6%, specificity 100%, 99.2% and 99.2%, and accuracy 82.0%, 92.1% and 94.2%, respectively. The sensitivity and accuracy of CNB or FNA/CNB for thyroid malignancy were significantly higher than those of FNA (P < 0.001). Compared with CNB alone, FNA/CNB was more accurate for thyroid malignancy only in small nodules less than 1 cm (P < 0.001).

CONCLUSIONS

Our clinical cohort data demonstrated that CNB was more accurate for the diagnosis of thyroid malignancy than FNA, and FNA/CNB was more accurate than CNB alone in small thyroid nodules. CNB will play a complementary role in optimal surgical decision-making and the management of thyroid nodules.

KEY POINTS

• CNB was more accurate for the diagnosis of malignancy than FNA. • Combined FNA/CNB was more accurate than CNB alone in small thyroid nodules. • CNB should play at least a complementary role in managing thyroid nodules.

[Epidemiology, pathophysiology, guideline-adjusted diagnostics, and treatment of thyroid nodules]

BACKGROUND

Clinically relevant thyroid carcinomas can be found in 5-6% of nodular goiters which undergo surgery. Moreover, multinodular goiters fre- quently contain hot areas. Therefore, efficient and rational methods for the differential diagnosis and decision are required to identify those nodules with an increased cancer risk or those which are hot among the many thyroid nodules.

METHODS

Description of a newly revised and further guidelines and consensus statements as well as selected literature search.

RESULTS

Already history, ultrasound and TSH (thyroid-stimulating hormone) determination do allow a first risk assessment for the further diagnostic work-up. Fine-needle biopsy (FNB) offers the best sensitivity and specificity for the distinction between benign and malignant thyroid nodules. The combination of several clinical and ultrasound criteria and laboratory determinations (calcitonin) can help with the selection of thyroid nodules with scintigraphically normal or decreased uptake > 1 cm for FNB. However, the efficiency of FNB requires sufficient training and experience of both the cytopathologist and the person performing FNB.

CONCLUSION

Whereas solitary thyroid nodules with a suspicion for malignancy should be referred to the surgeon, euthyroid thyroid nodules without clinical ultrasound or cytological indicators of malignancy may be followed up - possibly under medication -, if surgery is not indicated by local complaints, tracheal or mediastinal involvement.

Utility of malignancy markers in fine-needle aspiration cytology of thyroid nodules: comparison of Hector Battifora mesothelial antigen-1, thyroid peroxidase and dipeptidyl aminopeptidase IV

The purpose of this study was to compare the diagnostic interest of Hector Battifora mesothelial antigen-1 (HBME-1), thyroid peroxidase (TPO), and dipeptidyl aminopeptidase IV (DPP4) in thyroid fine-needle aspirates obtained from 200 resected thyroid lesions (55 colloid nodules, 54 follicular adenomas, 59 papillary cancers, and 32 follicular carcinomas). Hector Battifora mesothelial antigen-1 or TPO expression (% positive cells) and DPP4 staining score (12-point scale) were evaluated. Receiver operating characteristic (ROC) curves were plotted and optimal cutoff values for diagnosing malignancy were determined. The TPO ROC curve was consistently higher than the HBME-1 ROC curve. The TPO curve was also higher than the DPP4 curve with regard to sensitivity, but dipped below the DPP4 curve with regard to specificity. Using a cutoff value of <80% positive cells for TPO, >10% positive cells for HBME-1, and staining score > or =1 for DPP4, sensitivity to specificity ratios were 98-83% for TPO, 90-60% for HBME-1, and 88-80% for DPP4. Two particularly interesting findings of this study were the low negative likelihood ratio of TPO (0.02) allowing highly reliable exclusion of malignancy and the 100% specificity of DPP4 staining scores=12. Due to poor performance on follicular lesions, HBME-1 showed no advantage over TPO or DPP4.