Nondiagnostic Fine-needle Aspiration Biopsy Research Articles

Correlation of Thyroid Fine Needle Aspiration Biopsy With Histopathological Results.

Introduction Fine needle aspiration biopsy (FNAB) is an effective method used in the differential diagnosis of thyroid nodules. The Bethesda system has contributed to the determination of clinical approaches by bringing standardization to cytopathology reporting. However, the rate of cytological-histological incompatibility varies between 10% and 30%. Results differ according to clinics in the literature. These results create a need to reevaluate the efficacy and safety of fine needle aspiration biopsy. In this study, we aimed to evaluate the diagnostic accuracy of FNAB of thyroid nodules by correlating the cytopathology results of FNAB with the results of postoperative histopathology. Methods In this retrospective study, thyroid FNAB results and postoperative histopathology results of patients who underwent thyroidectomy operations in our clinic between January 2018 and December 2021 were compared. Accuracy, sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), false positive rate (FPR), and false negative rate (FNR) were calculated. Cases with nondiagnostic FNAB results were excluded from the calculations.FNAB results with a follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN) and suspicious for malignancy were included in the malignant group. Results A total of 304 patients were included in the study. The male/female ratio was 1:3.3. As a result of the study, malignancy was detected histopathologically in 47 (15.46%) patients. The commonest malignancy detected was papillary carcinoma. According to the Bethesda system, the results were evaluated in six categories. The incidence of malignancy in the Bethesda categories were 0%, 4%, 40%, 69.2%, 100%, and 100%, respectively. Accordingly, the specificity and sensitivity of FNAB for detecting malignancy were 98.7% and 66.6%, respectively. The accuracy was 93.5%. The false positive rate, false negative rate, positive predictive value, and negative predictive value were 1.20%, 33.3%, 91.4%, and 93.8%, respectively. Conclusion Thyroid FNAB is an effective method used with satisfactory reliability in the differential diagnosis of malignancies of thyroid nodules. Still, it has some limitations. This article demonstrates higher rates of malignancy in Bethesda categories III and IV. Therefore, clinical approaches are gaining importance in these categories.

Prevalence of thyroid cancer in hyperthyroidism: Identifying risk factors for malignancy

Objective: Contrary to the previously held belief that hyperthyroidism may be protective against the development of cancer, a growing number of studies suggest a link between hyperthyroidism and thyroid cancer. The purpose of this study is to investigate the incidence of malignancy in patients undergoing total thyroidectomy for hyperthyroidism with toxic adenoma (TA), toxic multinodular goiter (TMNG), and/or Graves' disease (GD), and to identify factors predictive of malignancy. Materials and Methods: This is a retrospective study of patients aged 18 years and older who underwent total thyroidectomy for toxic adenoma and toxic multinodular goiter associated with hyperthyroidism and Graves' disease. Thyroidectomies were performed by a single surgeon at a tertiary teaching hospital between January 2014 and December 2020. Our cohort was divided into two separate groups based on whether the pathology results were malignant or benign. Results: Between January 2014 and December 2020, 199 patients were included, 66.3% were female and the average age was 44.6 years. Hyperthyroidism cases included 52.7% toxic multinodular goiter (TMNG), 9.1% toxic adenoma (TA), and 38.2% Graves’ disease (GD). The cohort revealed a 32.6% thyroid cancer incidence in hyperthyroid patients. The leading malignancy was papillary carcinoma. Hyperthyroidism causes significantly predicted malignancy; TMNG had a 42.8% malignancy rate, compared to 22.4% for GD and 16.3% for TA (p=0.005). Fine needle aspiration biopsy (FNAB) findings were significant for malignancy prediction (p=0.001), with 62.9% malignancy after non-diagnostic FNAB results. Conclusion: The study emphasizes the need for careful consideration of malignancy risk in hyperthyroidism cases. Factors such as FNAB results and the type of hyperthyroidism condition significantly influenced malignancy prediction. The results underscore the necessity for a thorough evaluation of hyperthyroid patients at risk of malignancy.

FACTORS AFFECTING MALIGNANCY IN THYROID NODULES WITH NON-DIAGNOSTIC FINE NEEDLE ASPIRATION BIOPSY RESULT.

Non-diagnostic (ND) fine needle aspiration biopsy (FNAB) results are problematic for clinicians who want to accurately diagnose malignancy and avoid unnecessary thyroidectomies. In this study, we aimed to investigate the incidence of malignancy in nodules whose first FNAB result was ND, and ultrasonography (USG) findings affecting malignancy and the effectiveness of repetitive biopsies. In our clinic, 156 consecutive nodules whose first FNAB were ND according to the Bethesda system and underwent thyroidectomy between 1 January 2011 and 1 January 2018, directly or after repeated biopsies, were retrospectively analyzed. Malignancy was detected in 44 (28%) of 156 nodules that were ND in the first FNAB. Twenty-two (31%) of 72 nodules that underwent FNAB for the second time resulted in ND again. The malignancy rate of nodules with two consecutive ND results was 23%. Of the USG features, a significant correlation was found between malignancy and solid nodule structure (p<0.001), microcalcification (p=0.025), cervical lymphadenopathy (LAP) (p=0.004) and medium-high risk USG pattern (p=0.002). In multivariate analysis, only the solid nodule structure (p<0.002) and the presence of cervical LAP (p=0.013) resulted as independent predictive factors. Diagnostic thyroidectomy is an effective method for reaching the diagnosis in selected patients considering the USG findings.

The Role of Tc-99m-MIBI Scan in the Assessment of the Cystic Thyroid Nodule.

A non-surgical therapeutic option requires assurance that a cystic thyroid nodule with non-diagnostic cytology is benign. This work was undertaken to determine whether Tc-99m-MIBI scan (MIBI) findings can guide the best therapeutic option with confidence. We studied 81 cystic non-functioning thyroid nodules with non-diagnostic fine-needle aspiration biopsy (FNAB) report classified according to ATA 2015 ultrasonography (US) patterns for suspicion of malignancy. All had a MIBI to assess metabolic activity within the nodule as well as histopathological diagnosis. Diagnostic value analysis of MIBI as compared to the US pattern was determined. None of the 11 patients with US pattern of benign showed positive MIBI, and all had a histopathological report of benign. Diagnostic value of MIBI on US pattern of very low suspicion showed sensitivity, specificity, PPV, and NPV of 100%, 78.9%, 42.9%, and 100%, respectively. Our data shows that the only approach to a safe non-surgical treatment option in a cystic nodule with non-diagnostic FNAB is when no metabolic activity is seen on MIBI.

Predictive factors for recurrent non-diagnostic fine-needle aspiration biopsy in thyroid nodules

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Nondiagnostic Fine-Needle Aspiration Biopsy of Thyroid Nodules: Outcomes and Determinants.

Background: Nondiagnostic results are common following fine-needle aspiration biopsy (FNAB) of thyroid nodules, but recommendations for the management of these patients vary. We sought to determine the outcomes and predictors of nondiagnostic FNABs in a single-center cohort of patients undergoing thyroid nodule evaluation. Methodology: We identified all first time ultrasound-guided FNABs performed between May 2007 and June 2013 at the Beth Israel Deaconess Medical Center Thyroid Nodule Clinic and examined demographic data, follow-up ultrasounds, repeated FNABs, and histopathologic findings. We examined the likelihood of diagnostic findings and of cancer with increasing numbers of nondiagnostic evaluations with their exact binomial confidence intervals [CIs] and potential predictors of nondiagnostic status using generalized estimating equations. Results: During the six-year period, 2234 unique individuals underwent ultrasound-guided FNAB of a thyroid nodule. The probability of obtaining a diagnostic biopsy declined from 84.4% [95% CI 82.8-85.8%] for initial FNABs to 57.6% [CI 50.8-64.2%] for the first re-FNAB and further to 42.4% [CI 25.5-60.8%] for second re-FNABs. Adjusted risk of nondiagnostic FNAB strongly increased with increasing numbers of previous biopsies and was also higher among whites. The overall rate of diagnosis of malignancy after a nondiagnostic FNAB was 8.1% [CI 4.2-13.7%] and was similar regardless of the number of previous nondiagnostic aspirations. Conclusion: Following an initial nondiagnostic FNAB, the probability of yielding a diagnostic result declines with each sequential repeat FNAB. Nonetheless, a tangible possibility of malignancy remains even after repeated nondiagnostic FNABs.

Does the ACR TI-RADS scoring allow us to safely avoid unnecessary thyroid biopsy? single center analysis in a large cohort.

The American College of Radiology (ACR) has recently proposed a guideline that recommends clinicians to perform thyroid fine-needle aspiration biopsy (FNAB) on the basis of ultrasound features. In this study, we focused on nodules for which no biopsy is recommended by the ACR Thyroid Imaging, Reporting and Data System (TI-RADS) guideline. Two-thousand eight-hundred and forty-seven consecutive patients with thyroid nodules who underwent FNAB according to the 2009 American Thyroid Association (ATA) guideline were included. The nodules were re-classified according to the ACR TI-RADS guideline as benign (TR1), not suspicious (TR2), mildly suspicious (TR3), moderately suspicious (TR4) and highly suspicious (TR5). The TR3 category was stratified into two subcategories as regard to the nodule size (TR3; <25 mm and TR3; ≥25 mm). Two-hundred and thirty-three (8.2%) patients with non-diagnostic FNABs were excluded. When the TR2 and TR3; <25 mm categories were merged, FNAB was suggestive of thyroid cancer in 17 of 1382 patients (1.2%). FNAB revealed Bethesda IV-VI in 5 of 273 patients with the TR3; ≥25 mm category (1.8%), in 61 of 896 patients with the TR4 category (6.8%), and in 18 of 63 of patients with the TR5 category (28.6%). The ACR TI-RADS scoring was 98.8% (95% CI: 98 to 99.3) specific for identification of a benign nodule. Our data suggest that ACR TI-RADS scoring is an applicable and potentially cost-effective approach to determine thyroid nodules to be biopsied, although a small proportion of thyroid cancers would be missed.

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.

Comparison of 1869 thyroid ultrasound-guided fine-needle aspiration biopsies between general surgeons and interventional radiologists.

BackgroundThyroid nodules are commonly encountered problems in clinical practice. For patients who have a thyroid nodule, the fine-needle aspiration biopsy (FNAB) is the most important test, as it is the most reliable diagnostic method for distinguishing between benign thyroid nodules and cancerous nodules. FNAB is able to be performed either via an ultrasound (USG) or alone and is the first choice when it comes to diagnosing thyroid nodules, given that it is cheap, safe and provides accurate results.ObjectiveIn this study-a retrospective analysis of FNAB via USG - our aim is to evaluate the multiple variables related to FNAB procedures, including the experience of the person performing the biopsy, the age and gender of the patient, the number of nodules, the size of the nodule(s) and the number of lams recorded from the cytopathology report on non-diagnostic rates, conducted at an invasive radiology clinic and at a general surgery clinic.Materials and methodsA total of 1062 patients involving 1869 nodules, examined using FNAB via USG, were reviewed retrospectively from records dated between November 2011 and July 2014 and from pathology reports taken from the ANEAH General Surgery clinic and Interventional Radiology clinic. Cytopathology results were classified according to the 2007 Bethesda System for Reporting. Gender, age, number of nodules, diameter of the nodules, biopsied nodules, location of the nodules, number of lams, symptoms and the date of biopsies were the parameters used to examine the factors involved in non-diagnostic cytopathology invasive radiology. These parameters were inspected at both of the clinics (ANEAH General Surgery clinic and Interventional Radiology clinic). In analyzing the results, the statistical significance level was set at 0.05, where in cases that the p value was under 0.05 (p < 0.05), it was determined that no significant relationship existed. In this study, data were analyzed using SPSS 20 software.ResultsOf the nodules reviewed, 1620 were found on females and 249 on males. The age of the patients ranged from 10 to 87 years, with the mean age being 50 years. In the general surgery clinic, 470 nodules of 341 patients were aspirated, and in the interventional radiological clinic, 1399 nodules of 721 patients were aspirated. In the literature review conducted to compare statistical assessments of FNAB via USG, no significant difference was found between the ANEAH General Surgery clinic and the Invasive Radiology clinic (p > 0.05). In the invasive radiology clinic, non-diagnostic rates decreased with the increase in experience of the person who conducted the biopsy (p = 0.001).ConclusionThe results from both of the clinic's rates of non-diagnostic FNAB, performed via USG, were found to be acceptable. Our study also demonstrates that USG-guided FNAB can be performed with a low non-diagnostic rate as experience grows.

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

ObjectivesThyroid 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 methodsPubMed/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.ResultsEleven 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).ConclusionsCNB 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.

Nondiagnostic fine-needle aspiration biopsy results: our clinic experience

Nondiagnostic fine-needle aspiration biopsy results: our clinic experience

Evaluation of cytopathological findings in thyroid nodules with macrocalcification: macrocalcification is not innocent as it seems.

Microcalcification is strongly correlated with papillary thyroid cancer. It is not clear whether macrocalcification is associated with malignancy. In this study, we aimed to assess the result of fine needle aspiration biopsies (FNAB) of thyroid nodules with macrocalcifications. We retrospectively evaluated 269 patients (907 nodules). Macrocalcifications were classified as eggshell and parenchymal macrocalcification. FNAB results were divided into four groups: benign, malignant, suspicious for malignancy, and non-diagnostic. There were 79.9% female and 20.1% male and mean age was 56.9 years. Macrocalcification was detected in 46.3% nodules and 53.7% nodules had no macrocalcification. Parenchymal and eggshell macrocalcification were observed in 40.5% and 5.8% nodules, respectively. Cytologically, malignant and suspicious for malignancy rates were higher in nodules with macrocalcification compared to nodules without macrocalcification (p = 0.004 and p = 0.003, respectively). Benign and non-diagnostic cytology results were similar in two groups (p > 0.05). Nodules with eggshell calcification had higher rate of suspicious for malignancy and nodules with parenchymal macrocalcification had higher rates of malignant and suspicious for malignancy compared to those without macrocalcification (p = 0.01, p = 0.003 and p = 0.007, respectively). Our findings suggest that macrocalcifications are not always benign and are not associated with increased nondiagnostic FNAB results. Macrocalcification, particularly the parenchymal type should be taken into consideration.

Ultrasound-guided thyroid nodule biopsy: outcomes and correlation with imaging features

Background and purposeThyroid nodules are ubiquitous on ultrasound but have a low risk of malignancy. Hence, risk stratification is essential before biopysing them. We aim to (a) determine the frequency and predictors of nondiagnostic fine needle aspiration biopsy (FNAB) of thyroid nodules and (b) seek correlation between sonographic features and biopsy outcomes. MethodsBetween January 2010 and April 2013, 559 thyroid nodules underwent ultrasound-guided FNAB. Demographic information was obtained. Prebiopsy ultrasound images were reviewed for size, multiplicity, echotexture, shape, margins, vascularity, calcifications, cervical lymphadenopathy, and extrathyroid extension. Univariate and multivariate logistic regression analyses adjusting for the correlation between multiple nodules obtained from the same patient were performed. ResultsA total of 10.6% of the biopsies were nondiagnostic. Male gender [adjusted odds ratio (OR)=3.78, 95% confidence interval (CI) 1.87–7.66, P<.001] and a taller-than-wide shape (adjusted OR=3.22, 95% CI 1.34–7.75, P=.009) were independent predictors of a nondiagnostic FNAB. There was no significant association with cystic echotexture or a smaller nodule size. Well-defined irregular margins, microcalcifications, and coarse calcifications were independent predictors of malignancy, with specificities above 96% but low sensitivities (59.3%, 44.4%, and 11.1%, respectively). All nodules with cervical lymphadenopathy were malignant. If biopsy is performed when at least one of the above four features are present, the sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of predicting malignancy are 81.5%, 93.1%, 11.8 and 0.2 respectively. All purely cystic nodules and spongiform nodules were benign. ConclusionsMale gender and taller-than-wide thyroid nodules are independent risk factors for a nondiagnostic FNAB. Prudent use of a combination of sonographic features can help to risk-stratify thyroid nodules for FNAB and may reduce unwarranted FNABs.

Do repeatedly nondiagnostic fine needle aspirations of thyroid nodules predict malignancy risk?

Fine needle aspiration biopsy (FNAB) is a common, minimally invasive, cost-effective, and rapid method to manage thyroid nodules, but nondiagnostic FNAB (ND-FNAB) is still a common problem due to high prevalence (2%-20%). Our purpose in this study is to investigate risk of malignancy of repeating ND-FNABs and correlation between clinical and ultrasound findings. Our cohort study included 75 patients who had 2 or more times ND-FNABs and, finally, undergone surgical resection. We evaluated demographic, clinical, ultasonographic, and pathologic features. Fifty-seven patients were female, and 22 patients were male. Seventy-five patients' histopathologic results were 76% (n=57) benign and 24% (n=18) malignant. Of malignant nodules, 94.4% (n=17) were papillary carcinoma, whereas 5.6% (n=1) were follicular carcinoma. We did not find any predictive factor for malignancy and any differences associated with clinical and ultrasonographic features between benign and malignant nodules. Reaspiration followed by surgery for appropriate patients is recommended.

The Thyroid: Review of Imaging Features and Biopsy Techniques with Radiologic-Pathologic Correlation

Knowledge of the normal and abnormal imaging appearances of the thyroid gland is essential for appropriate identification and diagnosis of thyroid lesions. Thyroid nodules are often detected incidentally at computed tomography, magnetic resonance imaging, and positron emission tomography; however, ultrasonography (US) is the most commonly used imaging modality for characterization of these nodules. US characteristics that increase the likelihood of malignancy in a thyroid nodule include microcalcifications, solid composition, and central vascularity. Nuclear scintigraphy is commonly used for evaluation of physiologic thyroid function and for identification of metabolically active and inactive nodules. When fine-needle aspiration biopsy (FNAB) of a lesion is indicated based on clinical and radiologic features, appropriate US-guided biopsy technique and careful cytologic analysis are crucial for making the diagnosis. FNAB and core biopsy are the two percutaneous techniques used to obtain a specimen, with the latter technique being indicated following nondiagnostic or indeterminate FNAB. Specimen adequacy and diagnostic accuracy vary due to several factors, including location of aspiration and biopsy technique used. The radiologist must have a basic knowledge of thyroid disease, be familiar with specimen processing, and recognize the cytologic and radiologic appearances of thyroid lesions, all of which will facilitate the management of these lesions. Online supplemental material is available for this article.

“The Diagnostic Accuracy of Thyroid Nodule Fine-Needle Aspiration Cytology Following Thyroid Surgery: a Case–Control Study”

Thyroid surgery may cause regional scarring and some degree of fibrotic process which may extend into the perithyroidal soft tissues. This may result in problems when collecting thyroid fine-needle aspiration biopsy (FNAB) samples and evaluating the cellular abnormalities. This study aimed to determine if a history of thyroid surgery is a risk factor for nondiagnostic (ND) FNAB results. Patients with ≥1 discrete nodular lesion of the thyroid who underwent FNAB were included. The patients with a history of thyroid surgery constituted group 1, and the others constituted group 2. The factors which may influence FNAB results, including age, gender, presence of Hashimoto's thyroiditis, and ultrasound characteristics, were also evaluated. Group 1 included 123 patients with 200 nodules, and group 2 included 132 patients with 200 nodules. The two groups were similar with respect to demographic characteristics of the patients and ultrasonographic features of the nodules including diameter, content (cystic or solid), echogenicity, margin, and calcifications (P > 0.05). In all, 176 (44 %) of the participants had ND FNAB results. The median time interval between thyroid surgery and FNAB was 15 years [range, 1-45 years; interquartile range (IQR) 13 years]. Significantly more nodules in group 1 had ND FNAB results than in group 2 [98 (49 %) vs 78 (39 %), respectively, P = 0.028]. Multivariate analysis revealed that history of thyroid surgery was independently associated with ND FNAB [odds ratio (OR) 1.55, 95 % confidence interval (CI) 1-2.33, P = 0.033]. A history of thyroid surgery increases the risk of initial ND FNAB.

Is There a Role for On-Site Evaluation of Thyroid Fine Needle Aspiration to Reduce the Nondiagnostic Rate?

The use of immediate on-site evaluation of fine-needle aspiration biopsy (FNAB) specimens can determine the adequacy of specimens and provides a specific preliminary diagnosis. In this prospective study, we evaluated the impact of on-site assessment of thyroid FNAB performed under ultrasound guidance. Totally, 204 (170 female, 34 male) patients (102 on site, 102 control group) were included. The patients were randomized on site and regular cytologic examination groups. Quick May-Grünwald Giemsa stain was used for on-site examination and FNA was continued until adequate aspirate for optimal cytological examination. Two (2.0 %) of the 102 patients evaluated with on-site examination had a nondiagnostic result. However, 16 (15.7 %) of the 102 patients examined by regular cytologic examination method, had nondiagnostic result. The difference between these two groups was statistically significant (p < 0.0001). The major cause of a nondiagnostic thyroid FNAB specimen is the failure to aspirate a sufficient number of cells necessary for diagnosis cystic lesions. Immediate on-site evaluation can significantly decrease the nondiagnostic rate of thyroid FNAB specimens.

Needle washing increases the diagnostic yield of fine needle aspiration biopsy of the thyroid gland

Background and objective Nodular thyroid disease is a common condition in our clinical practice, and fine needle aspiration biopsy (FNAB) is the diagnostic procedure of choice. Its main limitation is the number of non-diagnostic samples. Since the Bethesda criteria were implemented in 2007 (a consensus document on the morphologic criteria and diagnostic terminology for interpretation of thyroid cytological samples), a higher prevalence of non-diagnostic FNAB was shown. In addition to the standard technique, we decided to collect and centrifuge the material remaining in puncture needles by washing them in a ThinPrep® solution, and to assess the increase in the diagnostic yield of FNAB after this change. Patients and methods Systematic sampling of 168 patients who underwent FNAB at the Nutrition and Endocrinology Department of the Xeral-Cies Hospital (Vigo, Spain) from January 2010 to November 2011 was done. Patients were classified into 2 groups: 75 patients in whom the residual material in the needle was not collected (non-washing group) and 93 patients in whom the material was collected (washing-group). All FNABs were performed by the same endocrinologist. Data are shown as percentage (±standard error) for ordinal variables or as mean (±standard deviation) for quantitative variables. A Chi-square test was used for statistical analysis of comparisons between percentages, and a Student's t-test for comparisons between quantitative variables. A value of p < 0.05 was considered statistically significant. Results No significant differences were found between the groups in age, sex, plasma TSH levels or nodule size. The rate of non-diagnostic FNABs was 44% (±0.06) in the non-washing group and 17.2% (±0.04%) in the washing group, with a significant difference (p < 0.01). Discussion Collection and subsequent processing of the residual material in the needle after FNAB significantly decreased the prevalence of non-diagnostic punctures in our patients. Collection of the residual material in the needle in this way is strongly recommended.

El lavado de la aguja aumenta la rentabilidad diagnóstica de la punción-aspiración con aguja fina de tiroides

Background and objectiveNodular thyroid disease is a common condition in our clinical practice, and fine needle aspiration biopsy (FNAB) is the diagnostic procedure of choice. Its main limitation is the number of non-diagnostic samples. Since the Bethesda criteria were implemented in 2007 (a consensus document on the morphologic criteria and diagnostic terminology for interpretation of thyroid cytological samples), a higher prevalence of non-diagnostic FNAB was shown. In addition to the standard technique, we decided to collect and centrifuge the material remaining in puncture needles by washing them in a ThinPrep® solution, and to assess the increase in the diagnostic yield of FNAB after this change. Patients and methodsSystematic sampling of 168 patients who underwent FNAB at the Nutrition and Endocrinology Department of the Xeral-Cies Hospital (Vigo, Spain) from January 2010 to November 2011. Patients were classified into 2 groups: 75 patients in whom the residual material in the needle was not collected (non-washing group) and 93 patients in whom the material was collected (washing-group). All FNABs were performed by the same endocrinologist. Data are shown as percentage (± standard error) for ordinal variables or as mean (± standard deviation) for quantitative variables. A Chi-square test was used for statistical analysis of comparisons between percentages, and a Student's t test for comparisons between quantitative variables. A value of p<0.05 was considered statistically significant. ResultsNo significant differences were found between the groups in age, sex, plasma TSH levels or nodule size. The rate of non-diagnostic FNABs was 44% (± 0.06) in the non-washing group and 17.2% (± 0.04%) in the washing group, with a significant difference (p < 0.01). DiscussionCollection and subsequent processing of the residual material in the needle after FNAB significantly decreased the prevalence of non-diagnostic punctures in our patients. Collection of the residual material in the needle in this way is strongly recommended.

Fine-Needle Aspiration Biopsy of Thyroid Bed Lesions in Post-Thyroidectomy Patients

The purpose of this study was to determine the importance of nondiagnostic fine-needle aspiration biopsy results for post-thyroidectomy bed lesions in patients with thyroid cancer. The Institutional Review Board approved this retrospective Health Insurance Portability and Accountability Act-compliant study with a waiver for informed consent. Twenty-one patients with nondiagnostic fine-needle aspiration biopsy of a thyroid bed lesion after thyroidectomy with at least 1 year of follow-up with neck imaging were retrospectively enrolled in our study. The tumor type, local staging, radiotherapy, serum thyroglobulin levels, and imaging characteristics of the thyroid bed lesions were recorded. All patients underwent sonographically guided fine-needle aspiration biopsy of the thyroid bed lesion. The mean imaging follow-up ± SD was 46.3 ± 28.7 months. Lesions in 20 patients (95.2%) were stable on imaging. Most thyroid bed lesions were hypoechoic (80.9%), and none showed calcifications. The mean thyroid bed mass maximum diameter was 1.17 ± 0.6 cm (range, 0.3-2.9 cm). Thyroid bed lesions with nondiagnostic fine-needle aspiration biopsy results after thyroidectomy can be managed with imaging follow-up; 1-year imaging is a reasonable interval after biopsy.