Underwent Thyroid Fine Needle Aspiration Research Articles

Elastography in the differential diagnosis of thyroid nodules.

Despite the publication of a recent meta-analysis of elastography in thyroid nodules, further work is necessary on this issue in different populations. In this study, we aimed to evaluate the clinical value of elastography on nodular goiters in mild iodine-deficient regions without excluding patients according to nodule characteristics. This prospective study was conducted between April 2010 and December 2011 in Yıldırım Beyazıt Dıskapı Research Hospital Endocrinology outpatient clinic. Five hundred twenty-eight nodular goiter patients who underwent thyroid fine-needle aspiration biopsy were included in our study. Elastography scores and indexes were measured with real-time ultrasound elastography (Hitachi® EUB 7000 HV machine with 13 MHz linear transducer). There were 471 females and 57 males and their ages ranged from 45 years to 78 years. A total of 601 nodules were evaluated in these patients. The area under the curve (AUC) for the elasto score was 0.91 (p < 0.0001) and AUC for the strain index (SI) was 0.96 (p < 0.0001). We suggest that the SI reflects malignancy better than the elasto score. We conclude that elastography scores greater than 3 have 76% sensitivity and 96% specificity for diagnosing malignancy. For SI, we conclude that 3.75 (83% sensitivity and 95% specificity) is the cutoff point. Elasto score and SI measurements of thyroid nodules in our population are efficient and increase the diagnostic performance of the sonography.

An independent study of a gene expression classifier (Afirma) in the evaluation of cytologically indeterminate thyroid nodules.

Molecular markers hold the promise of improved diagnostic yield in thyroid fine-needle biopsy. The Afirma gene expression classifier (GEC), available commercially, reports a negative predictive value of 94% in the diagnosis of benign nodules after indeterminate cytology. However, there are currently no independent studies of the performance of this assay. The aim was to assess the performance of the Afirma GEC in an academic medical center. Samples for the GEC were collected according to the manufacturer's recommended protocol from patients undergoing thyroid fine-needle aspiration. We requested GEC analysis on nodules reported cytologically as follicular neoplasm or atypia or follicular lesion of undetermined significance from patients willing to defer surgery. All patients undergoing thyroid fine-needle aspiration during the study period, whose cytology was reported as follicular neoplasm or atypia of undetermined significance/follicular lesion of undetermined significance, were offered access to the test and recruited to this study. PATIENTS whose GEC was "benign" were offered ultrasound follow-up in lieu of surgery. Those with a "suspicious" GEC were advised to undergo diagnostic lobectomy. The study was conducted at a large academic medical center. We measured the rate of benign and suspicious calls from the Afirma GEC and histological diagnosis after surgery. A total of 72 nucleic acid samples were sent for GEC analysis. In 12 (17%) of these samples, there was insufficient mRNA, leaving 60 Afirma results for analysis. Of these, 16 (27%) were benign, whereas 44 (73%) were suspicious. The rate of confirmed malignancy in GEC-suspicious nodules was only 17%. The Afirma GEC demonstrates a lower than expected rate of benign reports in follicular or Hürthle cell neoplasm and a lower than anticipated malignancy rate within GEC-suspicious nodules. These data suggest that the positive predictive value of the GEC is lower than previously reported and call into question the performance of the test when applied in the context of specialized academic cytopathology.

Correlation of Thyroid Cytology with Surgical Histology

Objective: 1) To assess the predictive value of thyroid cytology by fine needle aspiration (FNA) at our institution in detecting thyroid malignancy since the introduction of the Bethesda System. 2) To identify other potential predictors of malignancy. Method: Records of patients who underwent thyroid FNA and subsequent surgery at University of Missouri between 2007 and 2012 were reviewed. Data collected included cytologic and pathologic diagnoses as well as potential predictors of malignancy and demographic data, including radiation exposure, radiologic findings of calcification and increased vascularity, age, and gender. Results: A total of 378 cases were eligible for review. Of these, one-third met inclusion criteria. Cytology characterized as malignant or benign were found to have high concordance with surgical pathology findings. The diagnosis atypia of undetermined significance (AUS) and its malignancy risk were observed 2 to 3 times higher than that prescribed by the Bethesda guidelines. The majority of cases with cytologic features of follicular neoplasm were found to be benign. However, a significant number of incidental cases of papillary microcarcinoma were observed within this group. Papillary thyroid carcinoma was identified in 60% of cases with features suspicious for malignancy. Conclusion: While benign and malignant cytologies are highly predictive, there exists wide variation in the interpretation of uncertain categories. Malignancy risk associated with AUS ranges from 6% to 28% in the literature. These results suggest that trends developed from institution-specific data may be more predictive in guiding post-FNA management.

Thyroid Fine-Needle Aspiration&lt;subtitle&gt;Does Case Volume Affect Diagnostic Yield and Interpretation?&lt;/subtitle&gt;

To evaluate the effect of case volume on the diagnostic yield and interpretation of thyroid fine-needle aspiration (FNA). Retrospective case series. An academic tertiary referral center and 2 community hospital centers. Data were retrospectively reviewed for all consecutive patients undergoing thyroid FNA at these institutions during the 2009 calendar year. Differences in diagnostic distribution and yield among pathologists and clinicians of differing case volume. A total of 790 patients underwent thyroid FNA, with the results interpreted as benign (479 [60%]), atypical (166 [22%]), malignant (9 [1%]), or nondiagnostic (136 [17%]). The FNAs were performed by 134 physicians and interpreted by 16 pathologists with varying case volumes. Low-volume pathologists (<50 FNAs interpreted) were more likely to report atypical FNAs (32% vs 13%; P<.001) and less likely to call FNAs benign (50% vs 70%; P<.001) compared with high-volume pathologists (≥50 FNAs interpreted), and compared with expected normative data (benign, P<.001; atypical, P<.001). Atypical FNA findings reported by low-volume pathologist were more likely to yield benign permanent results than those read by high-volume pathologists (64% vs 42%; P<.02). Low-volume clinicians (<20 FNAs performed) were not more likely to perform nondiagnostic FNAs compared with high-volume clinicians (≥20 FNAs performed) (16% vs 15%; P=.47). Case volume significantly influences the pathologic interpretation of thyroid FNA, as low-volume pathologists report more atypical and fewer benign FNA results. Case volume did not have a significant impact on diagnostic yield, because thyroid FNAs performed by low-volume clinicians did not result in more frequent nondiagnostic results compared with those performed by high-volume clinicians.

Suspiciously malignant findings on ultrasound after fine needle aspiration biopsy in a thyroid nodule with initially benign ultrasound and cytologic result: to repeat or to follow-up

Purpose The purposes of this study were to evaluate the incidence of suspiciously malignant change on ultrasound (US) in thyroid nodules after initial benign US and cytologic results and to investigate the associated US characteristics and the management of these nodules. Materials and methods Among the patients who underwent thyroid fine needle aspiration biopsy (FNAB) from October 2003 to December 2004, 550 patients who had thyroid nodules with initial benign US and cytologic results were included. Reference standards were established by pathologic results, follow-up cytologic results or follow-up US. We evaluated the incidence of morphologic changes to suspiciously malignant US findings of these thyroid nodules after FNAB. We also evaluated the initial US features associated with the nodules showing suspiciously malignant findings on US after FNAB in these patients. Results Of 550 patients, 28 nodules (5.1%) showed morphologic changes into nodules with suspiciously malignant US findings on follow-up US. All thyroid nodules showing morphologic changes had mixed solid and cystic components ( P<.001). Suspiciously malignant changes on US were associated with the percentage of the cystic portion, but all changed nodules were confirmed as benign. Conclusion Follow-up US should be recommended rather than to repeat FNAB for thyroid nodules with initial benign US and cytologic results even if they later develop suspiciously malignant US features after FNAB.

Fine Needle Aspiration of the Thyroid: A Contemporary Experience of 3981 Cases

Fine needle aspiration (FNA) is an essential tool for the management of thyroid nodules. Recently, several national organizations have recommended FNA of all thyroid nodules >1 cm. With the increase use of imaging in the practice of medicine over the last decade, the number of incidentally discovered thyroid nodules is rising. Therefore, we analyzed our experience to determine if these changes in practice led to alterations in the population of patients undergoing FNA at our institution. Data were collected from 981 consecutive patients who underwent thyroid FNA at our institution between 2002 and 2009. Patients were divided in two groups: the early time period 2002-2005 (group 1) and later time period 2006-2009 (group 2). Data from the two groups were analyzed with t-test and χ(2) tests (SPSS, Inc., Chicago, IL). Comparing the groups, the number of FNAs performed in the later time period increased significantly by 250%. Patients in the later time period (group 2) were more likely to be female and were significantly older. With regard to FNA diagnoses, the number of benign FNAs increased, while the percentage of FNAs diagnosed as malignant and as follicular neoplasm decreased. There also appears to be an increase in the incidence of thyroiditis. The use of thyroid FNA has markedly increased during this contemporary series. This rise in thyroid FNA appears to be due to biopsy of benign thyroid nodules. With time, more females and older patients have undergone FNA, possibly reflecting the increased use of imaging studies in this patient population.

HMGA2 gene expression analysis performed on cytologic smears to distinguish benign from malignant thyroid nodules

Up to 80% of thyroid nodules with an indeterminate diagnosis on fine-needle aspiration (FNA) (eg, "suspicious for follicular neoplasm") prove to be benign at the time of surgical resection. Ancillary tests in current use are limited in their ability to improve the preoperative detection of malignant follicular thyroid nodules. Studies using paraffin-embedded tissue have indicated that high mobility group AT-hook 2 (HMGA2) overexpression is present in a high percentage of malignant thyroid neoplasms but not in benign thyroid neoplasms. In the current study, the ability of HMGA2 overexpression analysis to preoperatively distinguish benign from malignant thyroid nodules by reverse transcriptase-polymerase chain reaction (RT-PCR) on suspicious cytologic smears was evaluated. Patients who underwent thyroid FNA and subsequent thyroid resection from 2001 through 2007 were identified. A subset of these patients who had a cytologic diagnosis of "suspicious" underwent HMGA2 expression analysis. HMGA2 expression was detected on cells scraped from cytologic smears with 1-step, real-time quantitative RT-PCR. Of the 125 cases identified, RNA extraction and HMGA2 analysis were successful in 115 cases. With an HMGA2 overexpression change of 5.9-fold or greater compared with a thyroid tumor cell line as a positive cutoff, the test was found to have the following overall performance for detecting malignant nodules: sensitivity of 71%, specificity of 97%, positive predictive value of 94%, and negative predictive value of 84%. HMGA2 overexpression was found to have low sensitivity for detecting Hurthle cell carcinoma (33%). HMGA2 mRNA expression analysis can be performed on cytologic smears and demonstrates a high specificity and positive predictive value and relatively high sensitivity and negative predictive value for detecting malignancy in "suspicious" thyroid aspirate specimens.

Evidence‐based evaluation of the risks of malignancy predicted by thyroid fine‐needle aspiration biopsies

A National Cancer Institute (NCI) "Thyroid Fine-Needle Aspiration (FNA) State of the Science Conference" recently proposed standardized nomenclature and "risks of malignancies" associated with various diagnostic categories. We evaluated the evidence levels of the data used by NCI to predict malignancy risks and whether those estimates had clinical validity in our patient population.Eight hundred seventy-nine patients underwent thyroid FNA during 2006. FNA diagnoses were translated into NCI diagnostic categories, and 2-year follow-up retrospective information was obtained. Four percentages of malignancies were calculated for each diagnostic category using follow-up information from FNA, thyroidectomy, both, and all patients as denominators. 95% confidence intervals (CI) were estimated for all proportions, and results were analyzed with chi-square statistics. "Relative risk" calculations were performed using the percentage of malignancies in the entire population under study as a denominator.Most of the studies cited by the NCI provided incomplete and variable level III evidence based mainly on surgical follow-up. Among our patients, the percentages of malignancies calculated with follow-up data from all patients as the denominator were similar to the "risk estimates" proposed by the NCI, but estimates based on surgical follow-up overestimated the probability of thyroid malignancy for patients with FNA diagnosis of "benign" and "follicular lesions of undetermined significance" (FLUS). Relative risk and 95% CI calculations suggested that the NCI classification could be simplified into three categories: "benign," "FLUS + neoplasm," and "suspicious + malignant."

Prospective Trial Evaluating Electrical Impedance Scanning of Thyroid Nodules Before Thyroidectomy

Electrical impedance scanning (EIS) identifies tissue impedance changes associated with malignancy. Methods to distinguish benign from malignant thyroid nodules, particularly in patients with indeterminate cytology are lacking. To determine the diagnostic accuracy of EIS in the preoperative evaluation of thyroid nodules. From September 2002 to December 2006, 216 patients underwent thyroid fine needle aspiration (FNA) and EIS prethyroidectomy in this prospective cohort study. EIS, either positive or negative for malignancy, was correlated with final histopathology. A focal bright spot over a thyroid nodule correlating with increased conductivity and/or capacitance >25% baseline sternocleidomastoid muscle impedance defined positive EIS. Study endpoints were EIS accuracy, sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV). This study has been registered in the National Institutes of Health's public trials registry at ClinicalTrials.gov. The registration number is NCT00571077. EIS correctly diagnosed 96 of 110 patients with malignant and 75 of 106 patients with benign dominant thyroid nodules: Sn = 87%, Sp = 71%, PPV = 76%, NPV = 84%: overall EIS accuracy = 79%. Pretest cancer probability of 51% (110 of 216) increased to 76% (96 of 127) post-EIS, and preoperative use of EIS would result in a significant reduction (71%, 75 of 106) in number of operations performed for benign nodules. EIS performance was similar for 109 patients with indeterminate FNA: Sn = 83%, Sp = 67%, PPV = 61%, NPV = 87%, accuracy = 73%. Pretest probability of cancer increased from 39% (42 of 109) to 61% (35 of 57) post-EIS. The use of EIS would result in a significant reduction (67%, 45 of 67) in the number of purely diagnostic thyroidectomy for indeterminate FNA. EIS shows promise in differentiating thyroid nodules. Further EIS hardware and software optimization is warranted to improve upon the already favorable negative predictive value in indeterminate thyroid nodules.

Comparison of palpation-versus ultrasound-guided fine-needle aspiration biopsies in the evaluation of thyroid nodules

BackgroundThe aim of this study was to compare the results of palpation-versus ultrasound-guided thyroid fine-needle aspiration (FNA) biopsies.FindingsClinical data, cytology and histopathology results were retrospectively analyzed on all patients who underwent thyroid FNA biopsy in our outpatient endocrinology clinic between January 1998 and April 2003. The same investigators performed all thyroid FNAs (ASC) and cytological evaluations (KP). Subjects in the ultrasound-guided group were older, otherwise there were no differences in baseline characteristics (gender, thyroid function, the frequency of multinodular goiter, nodule diameter and nodule location) between groups. Cytology results in nodules aspirated by palpation (n = 202) versus ultrasound guidance (n = 184) were as follows: malignant 2.0% versus 2.7% (p = 0.74), benign 69.8% versus 79.9% (p = 0.02), indeterminate 1.0% versus 4.9% (p = 0.02), inadequate 27.2% versus 12.5% (p < 0.01). Malignant results were compared with Fisher's exact test. Other cytology categories were compared with chi-square test. Eighteen patients from the palpation- and 23 from ultrasound-guided group underwent surgery. In the palpation-guided group, the sensitivity of FNA was 100%, specificity 94%, positive predictive value 67% and negative predictive value 100%. In the ultrasound-guided group, the sensitivity of FNA was 100%, specificity 80%, positive predictive value 73% and negative predictive value 100%.ConclusionWe demonstrate that ultrasound guidance for thyroid FNA significantly decreases inadequate for evaluation category. We also confirm the high sensitivity and specificity of thyroid FNA biopsy in the diagnosis of thyroid cancer. Where available, we recommend universal application of ultrasound guidance for thyroid FNA biopsy as a standard component of this diagnostic technique.

Effectiveness of Toyota Process Redesign in Reducing Thyroid Gland Fine-Needle Aspiration Error

Our objective was to determine whether the Toyota Production System process redesign resulted in diagnostic error reduction for patients who underwent cytologic evaluation of thyroid nodules. In this longitudinal, nonconcurrent cohort study, we compared the diagnostic error frequency of a thyroid aspiration service before and after implementation of error reduction initiatives consisting of adoption of a standardized diagnostic terminology scheme and an immediate interpretation service. A total of 2,424 patients underwent aspiration. Following terminology standardization, the false-negative rate decreased from 41.8% to 19.1% (P = .006), the specimen nondiagnostic rate increased from 5.8% to 19.8% (P < .001), and the sensitivity increased from 70.2% to 90.6% (P < .001). Cases with an immediate interpretation had a lower noninterpretable specimen rate than those without immediate interpretation (P < .001). Toyota process change led to significantly fewer diagnostic errors for patients who underwent thyroid fine-needle aspiration.

Clinical features associated with an increased risk of thyroid malignancy in patients with follicular neoplasia by fine-needle aspiration.

The application of fine-needle aspiration (FNA) to the evaluation of the thyroid nodule has greatly enhanced the ability of the clinician to appropriately select patients for thyroidectomy. However, despite extensive experience with thyroid FNA, the cytological distinction of benign from malignant follicular neoplasia remains problematic. As a result, most patients with FNA findings of a follicular neoplasm are referred for thyroidectomy. The goal of the present study was to develop clinical criteria capable of predicting malignancy in patients with an FNA diagnosis of follicular neoplasm. Among 1121 patients undergoing thyroid FNA at two large teaching centers during the period 1990 to 1995, 149 patients had cytological findings consistent with a follicular neoplasm. Among 103 patients referred for thyroidectomy, 22 (21%) were found to have a malignancy in the biopsied nodule. Among patients subjected to thyroidectomy, the risk of malignancy was significantly higher when follicular neoplasia was present in a male (43% vs. 16% for females, p = 0.007), when the nodule was greater than 4 cm to palpation (40% vs. 13% for nodules less than 4 cm, p = 0.03), or when the nodule was judged to be solitary by palpation (25% vs. 6% for a dominant nodule in a multinodular goiter, p = 0.02). Bayesian analysis of the data reveals that after an FNA showing a follicular neoplasm, the risk of malignancy in males with large nodules was nearly 80%, compared with a rate of only 3% in females with small nodules. These results suggest that clinical features including gender, nodule size, and character of the gland by palpation can be systematically integrated into the decision analysis, thereby improving the selection of patients for surgical referral.