Value of re-aspirations in benign nodular thyroid disease

Value of repeated US-guided fine-needle aspiration (US-FNAB) in the follow-up of benign thyroid nodules: a real-life study based on the MoCyThy (Modena's Cytology of the Thyroid) DATABASE with a revision of the literature

PURPOSE

The utility of repeating ultrasound-guided fine-needle aspiration (US-FNAB) in the follow-up of benign (THY2) thyroid nodules is still debated. The aim of this study was to retrospectively investigate the diagnostic value of re-biopsy of thyroid nodules following an initially benign result.

METHODS

We retrospectively analyzed US-FNABs performed at the Unit of Endocrinology of Modena from 2006 to 2009. The firstly benign cytological result was compared with the cytological results of subsequent US-FNABs (2nd and/or 3rd) executed on the same nodule.

RESULTS

Among 10449 US-FNABs, 6270 (60%) received a THY2 cytological categorization. Of them, 278 (4.43%) underwent a subsequent US-FNAB: 86.7% maintained the same cytology, 32 (11.5%) changed to THY3 (indeterminate) and 5 (1.8%) to THY4 (suspicious of malignancy). Among the 24 nodules addressed to surgery, 9 (37%) were histologically malignant, with an overall miss rate of 3.2%. Male patients had higher risk of discordant results at subsequent US-FNAB (p = 0.005, OR:3.59, 95%CI:1.453-7.769) while dimensional increase above 5 mm was predictive of concordant benign cytology (p = 0.036, OR:0.249, 95%CI:0.068-0.915). Age, suspicious US characteristics, and distance between US-FNABs resulted not predictive.

CONCLUSIONS

Re-biopsy of benign nodules confirmed the benign nature in most cases. In case of discordant cytology, relocation in indeterminate category was the most common. The histological diagnosis of cancer occurred in one quarter of nodules surgically removed, with a low overall clinically significant miss rate. Thus, a small percentage of false negatives exists; males and subjects with US suspicious nodules should be carefully followed-up, considering case by case re-biopsy possibility.

[Clinical Approach for Thyroid Radiofrequency Ablation]

Radiofrequency ablation (RFA) is a non-surgical treatment for symptomatic, benign thyroid nodules. This treatment works by heating and destroying the nodule tissue, which results in reduction of its size and alleviation of the symptoms involved. RFA is indicated for nodules which are confirmed to be benign on two or more cytological or histological examinations, and which result in clinical symptoms requiring medical treatment. It is associated with good short-term outcomes on one-year follow-up; however, 20%-30% of the nodules regrow after more than three years. Therefore, on the basis of long-term follow-up, management of regrowth is key to patient care following RFA. Regrowth is more likely to occur in nodules that are large in size prior to RFA, and in those with high or increased vascularity. Recently, new techniques such as hydrodissection, artery-first ablation, and venous ablation have been introduced to inhibit regrowth. In addition, appropriate criteria for additional RFA should be applied to manage regrowth and prolong its therapeutic effects. RFA is essentially an alternative to surgery; therefore, the ultimate goal of this procedure is to avoid surgery permanently, rather than to achieve temporary effects.

SFE-AFCE-SFMN 2022 Consensus on the management of thyroid nodules : Follow-up: How and how long?

The SFE-AFCE-SFMN 2022 consensus deals with the management of thyroid nodules, a condition that is a frequent reason for consultation in endocrinology. In more than 90% of cases, patients are euthyroid, with benign non-progressive nodules that do not warrant specific treatment. The clinician's objective is to detect malignant thyroid nodules at risk of recurrence and death, toxic nodules responsible for hyperthyroidism or compressive nodules warranting treatment. The diagnosis and treatment of thyroid nodules requires close collaboration between endocrinologists, nuclear medicine physicians, surgeons, and other specialists. Therefore, this consensus statement was established jointly by 3 societies: the French Society of Endocrinology (SFE), French Association of Endocrine Surgery (AFCE) and French Society of Nuclear Medicine (SFMN); the various working groups included experts from other specialties (pathologists, radiologists, pediatricians, biologists, etc.). This section deals with the follow-up of thyroid nodules, low-grade tumors and microcarcinomas.

Is repeat fine needle aspiration required in thyroid nodules with initial benign cytology? Results from a large Irish series

BACKGROUND : Fine needle aspiration (FNA) cytology is the preferred method for assessing thyroid nodules for malignancy. Concern remains about the rate of false negative results. The primary aim of this study is to investigate the malignancy rate of thyroid nodules initially classified as benign (Thy 2).

METHODS

We retrospectively examined 658 nodules in 653 (429 female) patients between January 2013 to December 2017. All FNA biopsies (FNABs) were performed under ultrasound (US) guidance by a radiologist with expertise in thyroid pathology. Nodules were cytologically classified according to the UK Royal College of Pathologists guidelines. Decisions about further management were made at a regular thyroid multidisciplinary meeting. Follow up of the Thy 2 nodules was determined based on clinical and radiological criteria.

RESULTS

The mean age (± SD) was 53.2 (14.6) years. Five hundred out of 658 (76.0%) nodules were classified as Thy 2 (benign) after the first FNAB. Of these thyroid nodules initially classified as benign, 208 (41.6%) underwent repeat FNAB and 9 (1.8%) were surgically removed without repeat FNAB. The remainder were followed up clinically and/or radiologically. Seven (1.4%) of nodules initially classified as Thy 2 were later shown to be or to harbor malignancy after a follow-up of 74.5 (± 19.7) months. Papillary thyroid microcarcinomas were found co-incidentally in two thyroid glands of benign nodules, giving a true prevalence of 5/500 (1.0%).

CONCLUSIONS

With a well targeted FNAB, the false negative rate of an initial benign thyroid FNA is very low thus routine second FNAB is not required in patients with a thyroid nodule initially deemed benign. Multidisciplinary input is imperative in informing decision making.

Current Evaluation of Thyroid Nodules

Thyroid nodules may be discovered in a variety of settings. Familiarity with their management is important for medical specialists. Workup should start with history and physical examination, proceed to laboratory studies, and then to imaging. Nodules are selected for fine needle aspiration (FNA) biopsy based on imaging criteria. Most nodules can be accurately diagnosed on cytopathology, but some may require additional molecular testing to evaluate risk of malignancy. Patients with malignant lesions require additional investigation before referral to an experienced thyroid surgeon. Those who have benign lesions may require monitoring by periodic ultrasound to identify nodules requiring reevaluation.

Validation of American Thyroid Association Ultrasound Risk-Adapted Approach for Repeating Cytology in Benign Thyroid Nodules

Background: The 2015 American Thyroid Association (ATA) ultrasound (US) risk stratification system is used to identify thyroid nodules in which fine-needle aspiration cytology (FNAC) should be performed. In addition, this system is used to plan the long-term follow-up of patients with cytological benign thyroid nodules. The aim of our study was to evaluate the ATA US risk-adapted approach for repeating cytology in a large retrospective cohort of consecutive benign nodules with a second FNAC repeated after a median follow-up of 3.8 years (range 1.0-14.2 years). Methods: We retrospectively evaluated 1010 thyroid nodules, with an initial benign cytological diagnosis, that underwent at least one repeat FNAC during the follow-up. Results: The rate of missed cancer in the whole cohort of thyroid nodules was 1.0%, and it increased along by the US risk class (0.8% in very low/low-risk, 1.2% in intermediate-risk, and 3.1% in high-risk nodules). The 2015 ATA US risk stratification system showed a very high accuracy in selecting nodules that did not require a second FNAC (negative predictive value = 99.1%). In addition, the rate of missed cancer significantly increased along with the increase in the US risk class in nodules that showed an enlarged volume (0.4% in the low-risk class and 6.4% in the high-risk class, p = 0.005), while it was very low and not associated with the US features in the subgroup of thyroid nodules that did not grow during the follow-up (p = 0.96). Conclusions: Our results confirm the accuracy of the ATA recommendations in selecting benign nodules for FNAC repetition during the follow-up. An additional cytological evaluation maybe avoided in benign thyroid nodules with low-risk US features, regardless of the evidence of growth during the follow-up. While the utility of the routine repeat FNAC in all benign nodules with high-risk US features remains to be defined, based on our results, repetition of FNAC seems to be indicated in nodules with evidence of growth during the follow-up.

The value of repeating fine-needle aspiration for thyroid nodules

BACKGROUND

Fine-needle aspiration (FNA) is an invaluable technique used in the evaluation of thyroid nodules.

OBJECTIVES

Evaluate the concordance of results for consecutive FNA readings.

DESIGN

Retrospective, descriptive.

SETTINGS

Two tertiary care centers.

METHODS

Demographics were collected along with every FNA result and final pathology results for all patients (aged 9-90 years old) who underwent thyroid surgery from 2010 to 2017. The Bethesda system was used for cytology. Agreement levels were calculated and compared with final pathology.

SAMPLE SIZE

Of 1237 initially included, 1134 had at least one FNA performed with results available for review.

RESULTS

For the 1134 patients, demographic and clinical data were collection and a comparison was made between the three FNA results; the highest agreement was between FNA 2 and 3 (53.6%); however, the kappa value was consistently low for all comparisons, indicating a poor level of agreement overall. Also, the risk of malignancy was higher in this study than in the 2017 Bethesda system for reporting thyroid cytopathology in FNA cytology categories I and II.

CONCLUSION

Repeating FNA biopsies yield different results every time; hence, there is a low level of agreement. The clinical decision should therefore include other important risk factors. Prospective studies could help shed more light on this topic.

LIMITATIONS

Retrospective design.

CONFLICT OF INTEREST

None.

Natural History and Outcomes of Cytologically Benign Thyroid Nodules in Children

CONTEXT

Most pediatric thyroid nodules are cytologically benign, but few data exist to guide treatment.

OBJECTIVE

To describe the natural history and outcomes of cytologically benign, pediatric thyroid nodules.

DESIGN

Cohort study.

SETTING

Multidisciplinary thyroid clinic at an academic medical center.

PATIENTS

Consecutive pediatric patients (≤18 years old) with cytologically benign thyroid nodules evaluated between 1998 and 2016.

RESULTS

Cytologically benign nodules (N = 237) in 181 patients were followed by ultrasound (median follow-up, 3.4 years; range, 0.5 to 13.9 years) or to resection. Thyroid cancer was diagnosed in six nodules (2.5%), and all six patients were disease free after median follow-up of 4.9 years. Malignancy was more common in nodules >4 cm (15.4%; P = 0.037) or that grew during follow-up (6.0%; P = 0.048). The likelihood of nodule growth (±SE) was 15% ± 3%, 24% ± 4%, and 49% ± 10% at 6, 12, and 24 months, respectively. Among nodules >2 cm, those with ≥25% cystic content grew more slowly than nodules <25% cystic; nodules <2 cm grew similarly regardless of cystic content.

CONCLUSION

Benign cytology in pediatric thyroid nodules has a low false-negative rate similar to that in adults, and prognosis is excellent in the rare cases of malignancy. Resection of nodules >4 cm, combined with surveillance of smaller nodules and repeated aspiration for growth, detects most false-negative results. Follow-up ultrasound in 12 months is appropriate for most cytologically benign pediatric nodules, but delaying surveillance up to 24 months may be reasonable in large, predominantly cystic nodules.

2017 Thyroid Radiofrequency Ablation Guideline: Korean Society of Thyroid Radiology

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology (KSThR) developed recommendations for the optimal use of radiofrequency ablation for thyroid tumors in 2012. As new meaningful evidences have accumulated, KSThR decided to revise the guidelines. The revised guideline is based on a comprehensive analysis of the current literature and expert consensus.

Risk of malignancy in thyroid nodules: predictive value of puncture feeling of grittiness in the process of fine-needle aspiration

Fine-needle aspiration cytology (FNAC) is widely used for diagnosing thyroid nodules. However, there has been no specific investigation about the puncture feeling of grittiness. The aim of the present study was to see if the puncture feeling of grittiness during fine-needle aspiration procedure, combined with standard FNAC, could improve the accuracy in diagnosing thyroid cancer. A total of one thousand five hundred and thirty-one thyroid FNAC specimens acquired between January 2013 and January 2017 were retrospectively retrieved. All cases underwent surgical intervention. The FNAC diagnoses and puncture feeling of grittiness were evaluated and compared with the results of final histopathological diagnoses. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of diagnosis for thyroid nodules by FNAC alone, puncture feeling of grittiness alone, and the combination of FNAC plus grittiness were calculated respectively. The findings of our study suggest that puncture feeling of grittiness is a useful adjunct. Adding puncture feeling of grittiness to FNAC can significantly enhance the ability to differentiate malignant thyroid nodules from benign thyroid nodules. More importantly, we found that puncture feeling of grittiness is surprising trust-worthy in being near perfectly reproducible per individual radiologist, and among different operators.

Evaluation and management of thyroid nodules in children

PURPOSE OF REVIEW

The review is focused on new information about the presentation and management of thyroid nodules in children and adolescents.

RECENT FINDINGS

Palpable thyroid nodules are uncommon in children but many children have nodules detected by radiologic imaging. How to evaluate them, when to suspect thyroid cancer, and how best to follow apparently benign nodules has become an area of great interest. The American Thyroid Association recently published treatment guidelines for children with thyroid nodules and cancers but much has been learned since that publication.

SUMMARY

Personal and family history, ultrasound features, and fine needle aspiration cytology are used to determine the risk of cancer in thyroid nodules, which are then managed according to cancer risk.

2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the American Thyroid Association's (ATA's) guidelines for the management of these disorders were revised in 2009, significant scientific advances have occurred in the field. The aim of these guidelines is to inform clinicians, patients, researchers, and health policy makers on published evidence relating to the diagnosis and management of thyroid nodules and differentiated thyroid cancer.

METHODS

The specific clinical questions addressed in these guidelines were based on prior versions of the guidelines, stakeholder input, and input of task force members. Task force panel members were educated on knowledge synthesis methods, including electronic database searching, review and selection of relevant citations, and critical appraisal of selected studies. Published English language articles on adults were eligible for inclusion. The American College of Physicians Guideline Grading System was used for critical appraisal of evidence and grading strength of recommendations for therapeutic interventions. We developed a similarly formatted system to appraise the quality of such studies and resultant recommendations. The guideline panel had complete editorial independence from the ATA. Competing interests of guideline task force members were regularly updated, managed, and communicated to the ATA and task force members.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, use of molecular markers, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to screening for thyroid cancer, staging and risk assessment, surgical management, radioiodine remnant ablation and therapy, and thyrotropin suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using imaging and serum thyroglobulin, thyroid hormone therapy, management of recurrent and metastatic disease, consideration for clinical trials and targeted therapy, as well as directions for future research.

CONCLUSIONS

We have developed evidence-based recommendations to inform clinical decision-making in the management of thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

The natural history of the benign thyroid nodule: what is the appropriate follow-up strategy?

BACKGROUND

Long-term monitoring of benign thyroid nodules is not addressed in the present American Thyroid Association guidelines. The objective of this study was to determine the appropriate nature and length of follow-up for patients with a benign thyroid nodule.

STUDY DESIGN

A retrospective review was performed of all patients referred to single endocrine surgeon for evaluation of thyroid nodules between 2006 and 2012. The review included 263 patients who had benign fine needle aspiration (FNA) cytology and either underwent thyroidectomy or had at least a 1-year follow-up ultrasound. Main outcomes measures were repeat FNA and pathology results.

RESULTS

There were 231 women and 32 men. Forty-eight patients underwent immediate thyroidectomy, with pathology showing 2 papillary thyroid cancers (PTC), and 215 patients were followed with annual ultrasounds. During follow-up, 89 (41.3%) nodules underwent repeat FNA after initial biopsy. The repeat FNA cytology showed 91% benign, 7% follicular neoplasm, and 2% PTC. During follow-up, 81 (37.6%) patients underwent thyroidectomy after 3.3±2.8 years. Reasons for surgery included development of symptoms in 58 (71.6%), a non-benign repeat FNA in 8 (9.8%), or patient preference in 15 (18.5%). Surgical pathology identified 70 (86.4%) benign, 7 (8.6%) PTC, 3 (4%) follicular thyroid cancers, and 1 (1.2%) lymphoma. Median time from initial FNA to thyroidectomy in patients who had malignancy was 4.3 years. The maximum initial nodule size and average increase in nodule size did not differ between benign and malignant nodules (p=0.54 and p=0.75, respectively).

CONCLUSIONS

Significant numbers of benign thyroid nodules enlarge more than 5 mm over 3 years, triggering repeat FNA or thyroidectomy. Larger diameter nodules and more rapidly growing nodules were not predictive of malignancy. The practice of annually obtaining ultrasound for benign thyroid nodules should be discouraged.

[Repeated fine-needle aspiration cytology for the diagnosis and follow-up of thyroid nodules]

INTRODUCTION

The recently-proposed Bethesda reporting system has offered clinical recommendations for each category of reported thyroid cytology, including repeated fine-needle aspiration (FNA) for non-diagnostic and atypia/follicular lesions of undetermined significance, but there are no sound indications for repeated examination after an initial benign exam.

OBJECTIVE

To investigate the clinical validity of repeated FNA in the management of patients with thyroid nodules.

METHOD

The present study evaluated 412 consecutive patients who had repeated aspiration biopsies of thyroid nodules after an initial non-diagnostic, atypia/follicular lesion of undetermined significance, or benign cytology.

RESULTS

The majority of patients were female (93.5%) ranging from 13 to 83 years. Non-diagnostic cytology was the most common indication for a repeated examination in 237 patients (57.5%), followed by benign (36.8%), and A/FLUS (5.6%) cytology. A repeated examination altered the initial diagnosis in 70.5% and 78.3% of the non-diagnostic and A/FLUS patients, respectively, whereas only 28.9% of patients with a benign cytology presented with a different diagnosis on a sequential FNA.

CONCLUSIONS

Repeat FNA is a valuable procedure in cases with initial non-diagnostic or A/FLUS cytology, but its routine use for patients with an initial benign examination appears to not increase the expected likelihood of a malignant finding.

Repeat FNA Significantly Lowers Number of False Negative Results in Patients with Benign Nodular Thyroid Disease and Features of Chronic Thyroiditis

Purpose. The aim of the study was to compare the risk of thyroid malignancy and efficacy of repeat FNA in patients with thyroid nodules diagnosed cytologically as benign lesion (BL) with features of chronic thyroiditis (BL-CT) and BL without CT features (BL-nCT). Methods. The analysis included 917 patients with BL-CT and 7046 with BL-nCT in the first FNA. Repeat biopsy was carried out in 787 patients of BL-CT and 5147 of BL-nCT; 218 patients of BL-CT and 2462 of BL-nCT were operated; in 88 cases of BL-CT and 563 of BL-nCT both ways of follow-up were available. Results. Outcome of repeat cytology implied surgery more frequently in patients with BL-CT than with BL-nCT-3.2% versus 1.9%, P < 0.05. Incidence of cancer (including incidentalomas) was higher in patients with BL-CT operated after one benign cytology than in patients with two benign FNA outcomes: 10.8% versus 1.6%, P < 0.05. In patients with BL-nCT that difference was not significant: 3.2% versus 2.6%. Conclusions. Patients with thyroid nodules diagnosed as BL with CT features have higher risk of malignancy than patients with BL without CT features. Repeat biopsy significantly lowers percentage of FN results in patients with BL-CT in the first FNA.

Ultrasound elastography is not superior to grayscale ultrasound in predicting malignancy in thyroid nodules

BACKGROUND

Several studies have evaluated the ability of ultrasound elastography (USE) to diagnose malignant nodules. However, these studies had important limiting factors, selection bias and small sample size. The aims of the present study were to prospectively assess, in a large group of patients, the diagnostic power of USE for detecting malignancy in thyroid nodules, and to compare this technique with B-mode grayscale ultrasonography (BUS) and power Doppler ultrasonography (PD).

METHOD

There were 194 patients with 237 thyroid nodules who were examined using BUS, PD, and USE. USE scores were classified according to the elasticity: score 1 as high, score 2 as intermediate, and score 3 as low (i.e., a high degree of stiffness). Fine-needle aspiration cytology (FNAC) was performed in all nodules at least two different times. Nodules having two benign FNAC readings that did not change the diameter during a 6-month follow-up period were classified as benign. Patients having thyroid nodules with indeterminate, suspicious, or malignant cytology had total or hemithyroidectomy to remove the nodule and treat the malignancy.

RESULTS

Fifty eight (25%) nodules in 45 (23%) patients were found to be malignant. USE had a limited sensitivity and a positive predictive value in detecting malignant thyroid nodules and was not superior to BUS. USE had almost the same specificity and a negative predictive value as BUS. A power Doppler type-3 pattern was not of sufficient sensitivity to detect malignancies in thyroid nodules.

CONCLUSIONS

In contrast to earlier reports, this current study noted a lower sensitivity and specificity of USE for the diagnosis of malignancy in thyroid nodules than previously reported.

Thyroid nodule fine-needle aspiration

Thyroid nodules are a common clinical problem and are noted much more commonly on imaging examinations than are apparent by palpation. Fine-needle aspiration biopsy (FNA), which yields a cytology specimen for analysis, is the standard test to determine whether surgical removal of a detected nodule is recommended. This article will review the current guidelines for recommending FNA of thyroid nodules, the technique and risk of the procedure, and the implications for patient care based on FNA results. FNA has an essential role in the evaluation of patients with thyroid nodules to reduce the rate of unnecessary thyroid surgery for patients with benign nodules and triage patients with thyroid cancer to appropriate surgery. Before the routine use of FNA, approximately 14% of resected thyroid nodules were malignant, whereas with the current widespread use of thyroid nodule FNA, >50% of resected thyroid nodules are malignant. Historically, thyroid nodules were identified by physical examination of the neck, with a prevalence of approximately 5%-10% of adults in the United States, and these patients underwent palpation-guided FNA in the physician's office. In recent years, the increased use of sonography to examine the thyroid as well as cross-sectional imaging of the neck by computed tomography and magnetic resonance imaging has resulted in the detection of many nonpalpable nodules. In older adults, thyroid nodules may be detected in >67% of people screened by sonography. Fortunately, the vast majority of nodules are benign, but when they are discovered, an assessment regarding the need to exclude malignancy using FNA must be performed.

Value of repeat ultrasound-guided fine-needle aspiration in thyroid nodule with a first benign cytologic result: impact of ultrasound to predict malignancy

This study aimed to investigate the value of repeat ultrasound-guided fine-needle aspiration (FNAC-US) in benign thyroid nodules and determine the ultrasound (US) predictors of malignancy in this group of nodules. The authors studied 35 of 143 nodules with initially benign cytological result who underwent serial re-biopsy (FNAC-US). By means of surgery, malignancy histology results were confirmed in 10 (28.5%) cases (G1) versus 25 (71.5%) benign nodules (G2). The clinical, lab, scintigraphyc, and US features were compared between the two groups to predict malignancy in thyroid nodules with initially benign cytological result. The cytological finding of 28/35 nodules were change to indeterminate cytology (Bethesda system category III or IV) at second and/or ≥third cytological study. In this group of 28 cases, 23 (82.1%) was identified until the third procedure. The interval between first and third re-biopsy was 13 months (median). There were no differences in age, gender, thyrotropin (TSH) levels, thyroid auto-antibodies, or thyroid dysfunctions. The scintigraphy showed cold nodule in 80% of G1 versus 78.9% of G2 (NS). Sonographic studies showed malignant suspected US features in G1: microcalcifications, central flow, hypoechogenicity, and border irregularity. This study suggests repeating FNAC-US in nodules with first benign cytologic result and suspicious US features of malignancy for at least two times (until the third FNAC) in about 13 months horizon.

Diagnostic value and cost considerations of routine fine-needle aspirations in the follow-up of thyroid nodules with benign readings

BACKGROUND

Fine-needle aspiration (FNA) is the most accurate tool to identify malignancy in solitary thyroid nodules. Although some recommend routinely repeating FNA for nodules that are initially read as benign, there is no consensus. We evaluated clinical relevancy and considered costs of routine follow-up FNA in nodules initially read as benign.

METHODS

We reviewed the records of all 739 patients who underwent FNA of solitary thyroid nodules at our institution from 1988 to 2004. A total of 815 aspirations were required to obtain satisfactory specimens. According to their physicians practice, some patients had a "follow-up biopsy" after an initially benign FNA reading as a matter of routine (Group I approach) or if their clinical status changed (Group II approach). The outcome information for at least 4 years after the initial FNA in these two groups was compared. In addition, hypothetical costs relating to both methods for deciding whether to do a follow-up FNA were considered.

RESULTS

The initial FNA was benign in 576 (78%), suspicious for follicular neoplasms in 106 (14.4%), and malignant in 57 patients (7.7%). Follow-up FNA was performed in 292 patients with initially benign lesions, 235 in Group I approach and 57 in Group II approach. The FNA diagnosis according to Group I approach remained benign on follow-up biopsy in 96.2% (226/235), was altered to follicular neoplasm in 3% (7/235), and was suspicious for malignancy in 0.8% (2/235). When following Group II approach, the follow-up FNA was benign in 93% (53/57), undetermined in 1.7% (1/57), and showed follicular neoplasm in 5.3% (3/57). Combining Groups I and II methods, 5 of 292 patients had a malignant nodule on histological examination, a false-negative rate of 1.7% for the initial FNA, but without a difference in prevalence of thyroid malignancy between the groups. Cost-consequence analysis showed no benefit in routine follow-up FNA after initially benign FNA readings.

CONCLUSIONS

Routine follow-up FNA in patients whose initial FNA is benign has a low diagnostic upgrading value and is relatively costly. In patients whose initial FNA is benign, we recommend the FNA be repeated only if clinically suspicious signs or complaints develop.

An estimate of risk of malignancy for a benign diagnosis in thyroid fine-needle aspirates

BACKGROUND

The risk of malignancy for a benign diagnosis in a thyroid fine-needle aspiration is controversial because of lack of histologic follow-up.

METHODS

The author reviewed the results of all thyroid aspirations with surgical resection performed during the past 13 years at Baptist Hospital of Miami and Homestead Hospital, Homestead, Florida, combined these procedures with those in the literature, and correlated risk of malignancy with percentage of biopsies performed.

RESULTS

A total of 7089 aspirations and 1331 resections were performed. In the literature, the percentage of all benign cases that underwent resection ranged from 3% to 41%. Risk of malignancy decreased with an increased percentage of resections. The risk of malignancy for series with <8% of all benign aspirates resected was significantly higher than the risk for series with >or=8% of cases biopsied (15.1% vs 5.9%, P = .02). Logarithmic and linear estimates of risk of malignancy if 100% of cases were biopsied were 3% and 2.5%.

CONCLUSIONS

The best estimate of the risk of malignancy for a benign diagnosis in a thyroid fine-needle aspiration is 2.5%-3%. This level of risk is affected by the percentage of benign cases that are resected.

Does a repeated benign aspirate change the risk of malignancy after an initial atypical thyroid fine-needle aspiration?

Repeated fine-needle aspiration of the thyroid is sometimes recommended after an atypical diagnosis. However, histologic follow-up for patients with a benign second aspirate is limited. I reviewed the results of all thyroid aspirations with repeated aspirations and surgical resection for the last 13 years at Baptist Hospital, Miami, FL, and Homestead Hospital, Homestead, FL, and combined these with the results of intraoperative cytology and the literature. During the period, a total of 7,089 cases were aspirated and 1,331 resections were performed. There were 6 (1.7%) of 361 false-negative cases. Relevant intraoperative cytology was available for 24 cases. The order of the diagnoses (benign then atypical, atypical then benign) did not significantly affect the risk of malignancy (15% and 9%; P = .30). Patients with an atypical and benign diagnosis had a risk of malignancy (15%) higher than a single negative aspirate (3%; P < .001) and lower than that of patients with a single atypical diagnosis (27%; P < .001). Repeated aspirates are not independent events. Patients with a benign diagnosis after an atypical diagnosis have a risk of malignancy between the risks of a single benign or atypical diagnosis. Cytologists should strive to better communicate this risk.

Is a five-category reporting scheme for thyroid fine needle aspiration cytology accurate? Experience of over 18,000 FNAs reported at the same institution during 1998-2007

OBJECTIVE

Fine needle aspiration (FNA) has long been recognized as an essential technique for the evaluation of thyroid nodules. Although specific cytological patterns have been recognized, a wide variety of reporting schemes for thyroid FNA results have been adopted. This study reports our experience with a five-category reporting scheme developed in-house based on a numeric score and applied to a large series of consecutive thyroid FNAs. It focuses mainly on the accuracy of thyroid FNA as a preoperative test in a large subset of histologically distinct thyroid lesions.

METHODS

During the 1998-2007 period, 18,359 thyroid ultrasound-guided FNAs were performed on 15,269 patients; FNA reports were classified according to a C1-C5 reporting scheme: non-diagnostic (C1), benign (C2), indeterminate (C3), suspicious (C4), and malignant (C5).

RESULTS

Non-diagnostic (C1) and indeterminate (C3) FNA results totalled 2,230 (12.1%) and 1,461 (7.9%), respectively, while suspicious (C4) and malignant (C5) results totalled 238 (1.3%) and 531 (2.9%), respectively. Histological results were available in 2,047 patients, with thyroid malignancy detected in 840. Positive predictive value of FNA was 98.1% with a 49.0 likelihood ratio (LR) of malignancy in patients with a C4/C5 FNA report.

CONCLUSIONS

This five-category scheme for thyroid FNA is accurate in discriminating between the virtual certainty of malignancy associated with C5, a high rate (92%) of malignancy associated with C4, and a 98% probability of a histological benign diagnosis associated with C2. Further sub-classifications of C3 may improve the accuracy of the diagnostic scheme and may help in recognizing patients eligible for a 'wait and see' management.

Revised American Thyroid Association management guidelines for patients with thyroid nodules and differentiated thyroid cancer

BACKGROUND

Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. Since the publication of the American Thyroid Association's guidelines for the management of these disorders was published in 2006, a large amount of new information has become available, prompting a revision of the guidelines.

METHODS

Relevant articles through December 2008 were reviewed by the task force and categorized by topic and level of evidence according to a modified schema used by the United States Preventative Services Task Force.

RESULTS

The revised guidelines for the management of thyroid nodules include recommendations regarding initial evaluation, clinical and ultrasound criteria for fine-needle aspiration biopsy, interpretation of fine-needle aspiration biopsy results, and management of benign thyroid nodules. Recommendations regarding the initial management of thyroid cancer include those relating to optimal surgical management, radioiodine remnant ablation, and suppression therapy using levothyroxine. Recommendations related to long-term management of differentiated thyroid cancer include those related to surveillance for recurrent disease using ultrasound and serum thyroglobulin as well as those related to management of recurrent and metastatic disease.

CONCLUSIONS

We created evidence-based recommendations in response to our appointment as an independent task force by the American Thyroid Association to assist in the clinical management of patients with thyroid nodules and differentiated thyroid cancer. They represent, in our opinion, contemporary optimal care for patients with these disorders.

Comparison of cytological results obtained by repeated US-guided fine-needle aspiration biopsies of thyroid nodules: focus on the rate of malignancy and diagnostic concordance

The debate still continues on the repeated fine-needle aspiration biopsies (FNABs) for thyroid nodule in clinical practice. In this study, we determined the rate of cytological change to malignancy and the diagnostic concordance of repeated FNABs when the same nodules were targeted under US-guidance. We retrospectively reviewed data for 187 thyroid nodules (173: twice, 14: three times) from 160 patients who underwent repeated US-guided FNABs, which were performed by one skillful radiologist targeting for the same nodules at a mean interval of 7.5 months. Their initial cytological findings were compared with second or third results and histopathologic follow-up. The initial FNABs findings of 187 nodules were unsatisfactory, benign, and indeterminate in 56, 52, and 79 cases, respectively. The rate of a second cytological diagnosis changed to malignancy was significantly higher in the unsatisfactory aspirates (10.7%; 6/56), when compared with those of the benign (0.0%; 0/52) or of indeterminate aspirates (3.8%; 3/79) (P = 0.022). However, there was no change to malignancy at third cytological findings of all 14 nodules. After the second US-guided FNABs, 30.8% (16/52) of the initially diagnosed as benign aspirates were reclassified as indeterminate, while 26.6% (21/79) of the initially diagnosed as indeterminate were reclassified as benign. In conclusion, to identify malignancies, repeated US-guided FNABs are recommended for thyroid nodules initially classified as unsatisfactory aspirates. However, although US-guidance is applied, a discrepancy might be unavoidable in the cytological interpretation of the nodules classified as benign or as indeterminate aspirates because of overlapping cytological criteria.

US-guided fine-needle aspiration of thyroid nodules: indications, techniques, results

Fine-needle aspiration (FNA) biopsy of thyroid nodules is minimally invasive and safe and is usually performed on an outpatient basis. However, the optimal application of FNA requires not only technical skill but also an awareness of the limitations of the procedure, the indications for its use, the factors that affect the adequacy of the biopsy specimen, and the postprocedural management strategy. Ultrasonographic (US) features that are considered indications for FNA include single and multiple thyroid nodules. The results of FNA biopsy are operator dependent. In addition, the results may be affected by the lesion characteristics, the accuracy of lesion and needle localization, the method of guidance, the number of aspirated samples, the needle gauge, the aspiration technique, and the presence or absence of on-site facilities for immediate cytologic examination. With regard to postprocedural management, nodules that are diagnosed as benign on the basis of an adequate FNA specimen should be monitored with follow-up US. Circumstances that necessitate repeat FNA include sample inadequacy, nodule enlargement, cyst recurrence, or clinical or imaging findings that arouse suspicion about the presence of a malignancy even when cytologic findings in the biopsy specimen indicate benignity. Supplemental material available at radiographics.rsnajnls.org/cgi/content/full/28/7/1869/DC1.

Value of repeated fine needle aspirations of the thyroid: an analysis of over ten thousand FNAs

OBJECTIVE

Fine needle aspiration (FNA) has been accepted as the diagnostic method of choice in the initial evaluation of thyroid nodules. However, the value of repeated FNAs in the long-term follow-up of lesions initially diagnosed as benign is being questioned. Do the findings on initial FNA really spare patients thyroidectomy or do they only postpone it? The purpose of the present study is our attempt to answer this question.

DESIGN

Retrospective review of cytology reports of patients who underwent thyroidal FNAs at Washington Hospital Center from January 1998 through April 2006. All statistical analyses were done using the statistical package Splus.

MAIN OUTCOME

Patients who had thyroid nodules diagnosed as benign on FNA performed at our institution had a 90% probability of a benign diagnosis (with 95% confidence interval [0.87, 0.92]), when they underwent surgery. When the benign cytologic diagnosis was confirmed on a repeat aspiration, this probability increased to 98% (with 95% confidence interval [0.94, 1.0]).

CONCLUSIONS

Repeated thyroidal FNAs yielding benign diagnoses are nearly always accurate (98%), and therefore the patients can be followed safely without undergoing surgery, unless an unfavorable clinical change occurs.

Nódulos de tireóide e câncer diferenciado de tireóide: consenso brasileiro

Os nódulos tireoidianos constituem a principal manifestação clínica de uma série de doenças da tireóide com uma prevalência de aproximadamente 10% na população adulta. O maior desafio é excluir o câncer da tireóide, que ocorre em 5 a 10% dos casos. Os carcinomas diferenciados respondem por 90% dos casos de todas as neoplasias malignas da tireóide. A maioria dos pacientes com carcinoma diferenciado apresenta, geralmente, um bom prognóstico quando tratada adequadamente, com índices de mortalidade similares à população geral. No entanto, alguns indivíduos apresentam doença agressiva, desafiando o conhecimento atual e ilustrando a complexidade do manejo dessa neoplasia. No presente trabalho, reunimos 8 membros do Departamento de Tireóide da Sociedade Brasileira de Endocrinologia & Metabologia, para elaborarmos, por consenso, as diretrizes brasileiras no manejo dos nódulos tireoidianos e do câncer diferenciado da tireóide. Os membros participantes representam diferentes Centros Universitários do Brasil, refletindo diferentes abordagens diagnósticas e terapêuticas. Inicialmente, cada participante ficou responsável pela redação de determinado tema a ser enviado ao Coordenador, que, após revisão editorial e elaboração da primeira versão do manuscrito, enviou ao grupo para sugestões e aperfeiçoamentos. Quando concluído, o manuscrito foi novamente enviado e revisado por todos. A elaboração dessas diretrizes foi baseada na experiência dos participantes e revisão pertinente da literatura.

Comparison of palpation-guided fine-needle aspiration biopsy to ultrasound-guided fine-needle aspiration biopsy in the evaluation of thyroid nodules

OBJECTIVE

Although fine-needle aspiration biopsy (FNAB) of thyroid nodules is a reliable and simple method, the diagnostic value may be limited by inadequate and false-negative results. In this prospective study, we compared palpation-guided FNAB (PGFNAB) with ultrasound-guided FNAB (UGFNAB) to establish the rates of inadequate material and cost-effectiveness.

DESIGN

A total of 285 thyroid nodules in 215 patients were included in the study. Palpable nodules with the greatest diameter between 1 and 2.5 cm were included in the study. PGFNAB and UGFNAB techniques were applied to the same nodule by the same operator. Cytologic evaluations were performed by the same cytologist in a blinded fashion. To provide cost analysis, the prices obtained from different hospitals were evaluated.

MAIN OUTCOME

The rates of inadequate material for PGFNAB and UGFNAB were significantly different as 32.3% and 21.4%, respectively (p = 0.004). There was significantly higher inadequate material rate in PGFNAB group for small-sized nodules (greatest nodule diameter between 10 and 15 mm) (p = 0.009), despite inadequate material rate was not significant for both procedures for larger sized nodules. False-negative results were 15.8% for PGFNAB and 5.6% for UGFNAB. Regarding cost analysis, the difference between the two methods was 20 dollars on average for each patient.

CONCLUSIONS

We consider UGFNAB to be superior to PGFNAB for obtaining adequate material especially for small-sized nodules, as well as providing more accurate cytologic evaluation. Indeed, the difference between the costs of two procedures might be acceptable.

Eficacia diagnóstica de la punción-aspiración con aguja fina en pacientes con patología nodular tiroidea. Análisis de 510 casos

INTRODUCTION

The prevalence of palpable thyroid nodules in the general population is 4%-7%. Although most are benign, 5% are carcinomas. This study aimed to assess the efficacy of fine needle aspiration biopsy (FNAB) of thyroid nodules to diagnose malignancy and know the benefit of repeating the FNAB in the same nodule.

PATIENTS AND METHODS

A total of 510 patients (431 women and 79 men; mean age [standard deviation]: 47.6 [14.3] years) with surgery due to thyroid nodular condition between 1989 and 2002 and who had at least one FNAB prior to the surgery were studied.

RESULTS

The first FNAB was benign in 312 patients (61.2%), malignant in 38 (7.5%), suspicious or indeterminate in 97 (19%) and insufficient in 63 (12.4%). Sensitivity and specificity in the first FNAB for malignancy diagnosis was 76% and 84%, respectively. Successive FNABs had a moderate concordance and significance. However, repeating the puncture did not improve diagnostic performance, since sensitive increased (84%), but specificity worsened (79%) and the area under the ROC curve was similar. In the group with suspicious or indeterminate FNAB, histology was benign in 70% and malignant in 30%.

CONCLUSIONS

FNAB sensitivity and specificity for diagnosis of malignancy in thyroid nodules are high. Repetition of puncture on the same nodule does not improve diagnostic performance of the cytology. Among patients with suspicious FNAB, there is a high proportion of malignancy, which makes surgery necessary in these cases.

Molecular pathogenesis of euthyroid and toxic multinodular goiter

The purpose of this review is to summarize current knowledge of the etiology of euthyroid and toxic multinodular goiter (MNG) with respect to the epidemiology, clinical characteristics, and molecular pathology. In reconstructing the line of events from early thyroid hyperplasia to MNG we will argue the predominant neoplastic character of nodular structures, the nature of known somatic mutations, and the importance of mutagenesis. Furthermore, we outline direct and indirect consequences of these somatic mutations for thyroid pathophysiology and summarize information concerning a possible genetic background of euthyroid goiter. Finally, we discuss uncertainties and open questions in differential diagnosis and therapy of euthyroid and toxic MNG.

Repeated fine-needle aspiration of the thyroid in benign nodular thyroid disease: critical evaluation of long-term follow-up

Fine-needle aspiration (FNA) is the most effective diagnostic means in the management of nodular thyroid disease. Therefore, we decided to evaluate the diagnostic reproducibility of FNA and the usefulness of repeated FNA in benign nodular thyroid disease. We evaluated 799 satisfactory aspirations performed in 306 patients (298 females) aged 14-84 years, followed for 2-12 years. FNAs were performed on an annual basis. Of all patients, 299 (97.71%) maintained benignity: 230 (75.16%) repeated the same cytologic pattern, and 69 (22.54%) showed diagnostic variations within benign pathologies. In 3 patients (0.98%) the diagnosis changed to suspicious and in 4 (1.30%) to papillary carcinoma in the whole group. Of these 4 cases, 1 was diagnosed in the second (0.57%) and 3 in the third repeat FNA (2.25%). In 6 cases in which increased nodular size was observed, no change to malignancy was detected, while 3 of the carcinomas found showed no changes in size.

IN CONCLUSION

(1) The variation in cytologic diagnoses within benign pathologies can be attributed to the coexistence of nonuniform pathologies. Aspirations performed in different sites of the nodule would contribute to obtain a more representative specimen. (2) In the absence of suspicious clinical changes and with at least three FNAs confirming the cytologic diagnosis of benignity, the follow-up of nodules by FNA could be discontinued and (3) In our experience, the diagnostic change from benign to malignant after three repeat FNAs appears to indicate that it would be advisable to perform three procedures.

[Diagnosis of thyroid nodule. Application of evidence-based medicine]

OBJECTIVE

The frequency of thyroid nodules requires an appropriate and consistent undertaking of such pathology by the entire medical profession. Over the past few years, the ANAES (National Agency of Health Accreditation and Evaluation - 1995 - 1997) had formulated medical recommendations. Our work aimed at updating such recommendations considering recent literature developments and their level of evidence.

MATERIAL AND METHODS

We have selected high-level of evidence's articles published since 1997 dealing with the diagnostic undertaking of thyroid nodule. Such analysis was conducted using the search engine "Medline" and the level of evidence of the selected articles was evaluated by taking into account the professional recommendations of the "literature analysis and gradation of recommendations' guide" of ANAES.

RESULT

At present, two diagnostic tests are necessary in the diagnostic evaluation of a thyroid nodule (ultrasonography and fine-needle aspiration).

CONCLUSION

The medical recommendation will hence result in the synthesis of these two different diagnostic tests, nevertheless fine-needle aspiration being essential and having priority in evaluating the risk of cancer.

Ultrasound-detected thyroid nodules in radiation-exposed patients: changes over time

The relationship between radiation exposure and thyroid cancer is well known, but whether all irradiated patients should have thyroid ultrasounds is unresolved. We have performed follow-up ultrasound examinations of patients in a cohort who were exposed to conventional external radiation during 1939-63 for benign conditions of the head and neck area prior to their 16th birthday. Of 54 subjects who had normal radionuclide scans in 1974-76 and were reexamined in 1996-97 by thyroid ultrasonography, 42 remained eligible and 34 agreed to participate in the present ultrasound study. After an additional 4-8 years of follow-up and using an ultrasound machine with increased resolution, we found 160 nodules (in 33 of these 34 subjects), compared with 96 nodules (in 29 of the 34 subjects) detected in the previous examination. Only four of the new nodules were > or =10 mm. Of the previously diagnosed large (> or =10 mm) nodules, four nodules in four subjects resolved; nine nodules in six subjects regressed to <10 mm; 14 nodules in 13 subjects remained at > or =10 mm. The four new large nodules appeared in four subjects, and six small nodules increased to > or =10 mm in six other subjects. The total volume of the thyroid nodules decreased in the 13 subjects on thyroid hormone (by 0.20 cm(3)) and increased in the 21 subjects who were not (by 0.34 cm(3), p < 0.05 by unpaired t-test). In summary, thyroid nodules are extremely common in irradiated subjects. Many new ones may be observed over time, but most are small and seen because of the increased resolution of ultrasound machines. Compared to patients on no medication, nodules in patients on thyroid hormone tended to regress. Since FNA of all thyroid nodules in irradiated patients is not feasible, ultrasound is useful in identifying those lesions that are growing.

[Incidence of malignant lesions in patients with clinically benign thyroid nodules: observational and prospective study in a cohort of 50 patients followed during two years]

INTRODUCTION

To study the frequency of malignant lesions in patients with clinically benign thyroid nodules and the value of the repetition of fine needle aspiration biopsy (FNAB).

METHODS

Observational and prospective 2-year study in a cohort of 50 patients with clinically benign thyroid nodules. Patients were initially submitted to clinical examination, ultrasound (US) and FNAB1 patients, followed by a second FNAB and US.

RESULTS

Palpation is not a good test for diagnosis and follow-up of thyroid nodules. On the other hand, the initial consideration that these patients should harbor benign lesions is a very useful parameter, since 47/50 patients (94%) did not present malignant lesions during the follow-up. FNAB1 and FNAB2 were concordant in 33/39 patients when FNAB1 was negative (85%); 11 patients were operated, 8 by suspicious FNAB and 3 due to nodule growth. We observed 2 patients with non-invasive papillary microcarcinoma and 1 patient with papillary carcinoma outside of the main nodules.

CONCLUSION

there was concordance between initial clinical benign diagnosis, FNAB and the follow-up. In one case there was a papillary carcinoma. In addition, ultrasonography should be considered for all patients with suspected thyroid nodules. Finally, we demonstrated that a second cytology usually confirms the result of the first cytology in benign thyroid nodules.