American Association of Clinical Endocrinologists, Associazione Medici Endocrinologi, and EuropeanThyroid Association Medical Guidelines for Clinical Practice for the Diagnosis and Management of Thyroid Nodules

Preoperative discrimination of benign from malignant disease in thyroid nodules with indeterminate cytology using elastic light-scattering spectroscopy

Thyroid nodules are common and often require fine needle aspiration biopsy (FNAB) to determine the presence of malignancy to direct therapy. Unfortunately, approximately 15-30% of thyroid nodules evaluated by FNAB are not clearly benign or malignant by cytology alone. These patients require surgery for the purpose of diagnosis alone; most of these nodules ultimately prove to be benign. Elastic light scattering spectroscopy (ESS) that measures the spectral differences between benign and malignant thyroid nodules has shown promise in improving preoperative determination of benign status of thyroid nodules. We describe the results of a large, prospective, blinded study validating the ESS algorithm in patients with thyroid nodules. An ESS system was used to acquire spectra from human thyroid tissue. Spectroscopic results were compared to the histopathology of the biopsy samples. Sensitivity and specificity of the ESS system in the differentiation of benign from malignant thyroid nodules are 74% and 90% respectively, with a negative predictive value of 97%. These data suggest that ESS has the potential for use in real time diagnosis of thyroid nodules as an adjunct to FNAB cytology.

Thyroid nodule with benign cytology: is clinical follow-up enough?

Objective

In this multicenter study, we investigated the management algorithm for thyroid nodules with benign cytology using US features from data collected from 7 institutions.

Materials and Methods

The institutional review board approved this retrospective study. Data on 700 focal thyroid nodules in 673 consecutive patients were collected from 7 university-affiliated hospitals. This study included nodules that were diagnosed as benign at initial cytologic evaluation and that underwent pathologic or follow-up study. The risk of malignancy was compared according to the US assessments of each institution as well as looking at all the nodules together as a whole.

Results

Of the 700 nodules, 688 (98.3%) were benign and 12 (1.7%) were malignant. If initial cytologic results were benign, the likelihood of the nodule actually being malignant was from 1 to 3%, varying by institution. The likelihood of a cytologically benign nodule with positive US being malignant (4.7%, 8/169) was higher than that of one without positive US (0.8%, 4/531) (P = .002).

Conclusion

Based on our multicenter study, repeat FNA should be performed in thyroid nodules with initial benign cytology showing suspicious US features in order to decrease the number of false negative cases.

Increased incidence of thyroid cancer in Latina, Italy: a possible role of detection of subclinical disease

OBJECTIVE

To describe the thyroid cancer incidence trends and geographical patterns in the Latina Province of Lazio, Italy using the population-based cancer registry.

METHODS

We extracted from the Latina cancer registry all cases of thyroid cancer from 1997 to 2006. Cases were classified according to morphological type and diameter. Data for diagnostic procedures for Latina Province residents from 2001 to 2006 were extracted from the regional outpatient procedures information system.

RESULTS

A total of 982 cases were diagnosed, for a standardized incidence of 8.3 and of 27.9 per 100,000 in males (n, 220) and in females (n, 762), respectively. The annual percent change (APC) was +16.7% (95% CI +7.2, +27.2) and +10.5% (95% CI +6.5, +14.6) in males and females, respectively. The increase was mostly due to papillary (n, 759) and small (≤20 mm) cancers (n, 617), with no difference by age (<45 years; n, 431). The APC of neck ultrasound performed was +8.7% (95% CI +0.1, +18.1) and +9.0% (95% CI +1.1, +17.4) and that of biopsy/cytology was +17.0% (95% CI +13.0, +21.3) and +16.6% (95% CI +6.2, +28.1) in men and women, respectively. The geographic pattern of biopsy/cytology was similar to that of cancer incidence but not to that of neck ultrasound.

CONCLUSIONS

In Latina, the increase in thyroid cancer incidence was more rapid than in the rest of Italy, particularly for types with a good prognosis. While tumor size and histotype suggest an increase in detection instead of an increase in disease occurrence, data on diagnostic procedure reimbursements cannot provide an explanation.

Standardized Ultrasound Report for Thyroid Nodules: The Endocrinologist's Viewpoint

BACKGROUND

Ultrasonography (US) plays a crucial role in the diagnostic management of thyroid nodules, but its widespread use in clinical practice might generate heterogeneity in ultrasound reports.

OBJECTIVES

The aims of the study were to propose (a) a standardized lexicon for description of thyroid nodules in order to reduce US reports of interobserver variability and (b) a US classification system of suspicion for thyroid nodules in order to promote a uniform management of thyroid nodules.

METHODS

RELEVANT PUBLISHED ARTICLES WERE IDENTIFIED BY SEARCHING MEDLINE AT PUBMED COMBINING THE FOLLOWING SEARCH TERMS: ultrasonography, thyroid, nodule, malignancy, carcinoma, and classification system. Results were supplemented with our data and experience.

RESULTS

A STANDARDIZED US REPORT SHOULD ALWAYS DOCUMENT POSITION, EXTRACAPSULAR RELATIONSHIPS, NUMBER, AND THE FOLLOWING CHARACTERISTICS OF EACH THYROID LESION: shape, internal content, echogenicity, echotexture, presence of calcifications, margins, vascularity, and size. Combining the previous US features, each thyroid nodule can be tentatively classified as: malignant, suspicious for malignancy, borderline, probably benign, and benign.

CONCLUSIONS

We propose a standardized US report and a tentative US classification system that may become helpful for endocrinologists dealing with thyroid nodules in their clinical practice. The proposed classification does not allow to bypass the required cytological confirmation, but may become useful in identifying the lesions with a lower risk of neoplasm.

Thyroid cancer in Plummer's disease

Thyroid cancer with concomitant hyperthyroidism is rare. Most foci of malignancy are small and seen postoperatively as incidental findings after surgery for hyperthyroidism. Thyroid masses with clinical features of malignancy and concomitant hyperthyroidism are less-commonly reported. We report two cases of multinodular toxic goitre or Plummer's disease with clinical features of malignancy. Both patients had large multinodular goitres with evidence of metastasis to the manubrium for the first patient and to the lymph node and lungs for the second patient. Both were clinically euthyroid but with free hormone excess and suppressed thyroid stimulating hormone (TSH) on laboratory testing. Both patients received methimazole prior to thyroidectomy. Histopathology revealed follicular variant of papillary cancer with metastasis to the manubrium for the first patient and follicular thyroid cancer with lymph node metastasis for the second. While rare, thyrotoxicosis can occur with malignancy, Plummer's disease may harbour cancer and behave aggressively.

Follicular variant of papillary thyroid carcinoma presenting as toxic nodule in an adolescent: coexistent polymorphism of the TSHR and Gsα genes

BACKGROUND

Autonomously functioning, "hot", thyroid nodules are not common in children and adolescents. Such nodules are not considered alarming because they are assumed to be benign adenomas. Herein, we present a 15-year-old girl with a papillary thyroid carcinoma of 3.5 cm in diameter, which was functionally autonomous and scintigraphically hot.

PATIENT FINDINGS

The patient, initially referred to our Endocrine Unit because of a thyroid nodule, returned 6 months later for symptoms of hyperthyroidism. Hyperthyroidism was confirmed biochemically. Radioactive iodine ((131)I) thyroid scintigraphy was consistent with an autonomous thyroid nodule. As per guidelines, the patient underwent surgery and a pathological examination revealed papillary carcinoma, follicular variant. The excised nodule was examined for activating mutations of the thyrotropin receptor (TSHR), Gsα (GNAS1), H-RAS, N-RAS, K-RAS, and BRAF genes by direct sequencing. No mutations were found. Nevertheless, two combined nonfunctioning mutations were detected: a single-nucleotide polymorphism (SNP) of the TSHR gene, in exon 7, at codon 187 (AAT→AAC, both encoding asparagine), and a SNP within exon 8 of the Gsα gene at codon 185 (ATC→ATT, both encoding isoleucine). Both SNPs were also identified in the germline DNA of the patient. The same SNPs were sought in the parents and brother of our patient. Her father was heterozygous for the TSHR SNP, her mother heterozygous for the Gsα SNP, and her brother was wild type.

CONCLUSIONS

This case demonstrates that the presence of hyperfunctioning thyroid nodule(s) does not rule out cancer and warrants careful evaluation, especially in childhood and adolescence to overlook malignancy.

A randomized trial of hemithyroidectomy versus Dunhill for the surgical management of asymmetrical multinodular goiter

OBJECTIVE

To assess the immediate and long-term clinical results of 2 different surgical procedures for the treatment of asymmetrical multinodular goiter (AMG).

BACKGROUND

Half of the patients presenting with a single benign thyroid nodule have contralateral subclinical disease. There is a controversy whether these patients should be treated with hemithyroidectomy (HMT) or with a more extensive procedure.

METHODS

Adult patients with a benign unilateral dominant nodule and contralateral nodule(s) with a diameter of less than 10 mm detected on neck ultrasonography were randomized to HMT or Dunhill (DUN). Rates of complications, remnant growth, incidental carcinoma, and reoperation were assessed.

RESULTS

A total of 118 patients (F/M:110/8, mean age 43 years) were included and randomized: 65 to HMT and 53 to DUN. After randomization, 28 patients were excluded leaving 47 HMT and 43 DUN long-term (55 ± 35 months) evaluable patients. Mean nodule size was 38 and 6 mm for the dominant and contralateral nodules, respectively. No differences were found in operative time, accidental parathyroidectomy, parathyroid autotransplantation, or wound complications. Transient hypocalcemia was more common in DUN (30% vs 8%; P < 0.001). No permanent complications were observed. At the last follow-up visit, thyroid-stimulating hormone was similar in both groups. Remnant growth (20 vs 0%; P < 0.001), appearance of new nodules (55 vs 14%; P < 0.001), and overall reoperation rate (9.2 vs 1.8%, P = 0.2) were more common in HMT, mostly because of undiagnosed cancer requiring completion thyroidectomy. Thirty percent of HMTs developed hypothyroidism and required long-term T4 supplementation.

CONCLUSIONS

DUN appears superior to HMT for the treatment of AMG in terms of early reoperation for missed carcinomas and disease progression. Both procedures have a similarly uneventful postoperative course.

Overview of molecular biomarkers for enhancing the management of cytologically indeterminate thyroid nodules and thyroid cancer

OBJECTIVE

To provide information on molecular biomarkers that can help assess cytologically indeterminate thyroid nodules.

METHODS

Published studies on immunohistologic, somatic mutation, gene expression classifier, microRNA, and thyrotropin receptor messenger RNA biomarkers are reviewed, and commercially available molecular test panels are described.

RESULTS

Thyroid nodules are common, and clinical guidelines delineate an algorithmic approach including serum thyroid-stimulating hormone measurement, diagnostic ultrasound examination, and, when appropriate, fine-needle aspiration (FNA) biopsy for determination of a benign versus malignant status. In clinical practice, approximately 20% of FNA-derived cytology reports are classified as "indeterminate" or follicular nodules that do not fulfill either benign or malignant criteria. In this setting, the actual risk for malignancy of a cytologically indeterminate nodule ranges from approximately 15% to 34%. Research describing molecular biomarkers from thyroid cancer tissue has been applied to FNA-derived thyroid nodule material. There is also a serum molecular marker that has been reported with goals similar to those for the FNA-derived molecular markers: to enhance the preoperative diagnosis of thyroid cancer and reduce the large number of patients who have a diagnostic surgical procedure for benign thyroid nodules.

CONCLUSION

Progress toward the foregoing goals has been made and continues to evolve with the recent appearance of molecular biomarker tests that can be selectively applied for further assessment of cytologically indeterminate thyroid nodules.

Intrinsic factors affecting adequacy of thyroid nodule fine-needle aspiration cytology

OBJECTIVE

To evaluate intrinsic nodule features predictive of an inadequate report in fine-needle aspiration cytology (FNAC).

DESIGN

Single-centre cross-sectional study.

METHODS

Between May 2005 and April 2011, 3279 ultrasonography-assisted FNACs were carried out and features of nodules recorded prospectively. Univariate logistic regression analyses were performed to estimate the association between nondiagnostic cytology and variables such as age, gender, single nodule, maximum nodule diameter and estimated volume.

RESULTS

Inadequate or nondiagnostic samples were reported in 1195 FNACs. All diameters were found to be predictors of nondiagnostic cytology; estimated nodule volume, on the other hand, was not. Nodules with a diameter <10 mm were more frequently nondiagnostic (OR 1.65, 95% CI 1.40-1.94, P < 0.001). Neither micro- nor macrocalcification increased the risk of inadequacy. On the contrary, mixed lesions were more frequently diagnostic (OR 0.68, 95% CI 0.85-0.80, P < 0.001). Solid nodule aspiration was performed more easily on isoechogenic nodules (OR 0.64, 95% CI 0.54-0.77, P < 0.001); the same procedure was more cumbersome on hypoechogenic lesions (OR 1.87, 95% CI 1.62-2.16, P < 0.001). Increased vascularization did not cause a significant increase in the nondiagnostic results. Blurred margins increased the inadequacy rate (OR 1.45, 95% CI 1.24-1.69, P < 0.001), while presence of a hypoechogenic halo decreased it (OR 0.67, 95% CI 0.54-0.82, P < 0.001).

CONCLUSIONS

Some ultrasonographic features suggestive of malignancy may be predictive of inadequate cytology. Patients must be notified that the FNA report may be nondiagnostic and that this represents a limitation of the technique related to the structure of lesions.

Use of radiofrequency ablation in benign thyroid nodules: a literature review and updates

Successful thermal ablation using radiofrequency has been reported in various tumors including liver or kidney tumors. Nonsurgical minimally invasive ablative therapy such as radiofrequency ablation (RFA) has been reported to be a safe and efficient treatment option in managing symptomatic cold thyroid nodules or hyperfunctioning thyroid nodules. Pressure and cosmetic symptoms have been shown to be significantly improved both in the short and long terms after RFA. For hyperfunctioning thyroid nodules, RFA is indicated for whom surgery or radioiodine are not indicated or ineffective or for those who refuse surgery or radio-iodine. Improvement of thyroid function with decreased need for antithyroid medications has been reported. Complication rate is relatively low. By reviewing the current literature, we reported its efficacy and complications and compared the efficacy of RFA relative to other ablative options such as ethanol ablation and laser ablation.

'Suspicious for a follicular neoplasm' before and after the Bethesda System for Reporting Thyroid Cytopathology: impact of standardized terminology

BACKGROUND

The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) standardized the terminology for indeterminate diagnoses, but the performance of the indeterminate categories before and after TBSRTC has not been compared. This study evaluates the 'suspicious for a follicular or Hürthle cell neoplasm' (SFN/HCN) category before and after the introduction of TBSRTC at a single institution and in a meta-analysis of the literature.

METHODS

A meta-analysis compiled findings from publications on SFN/HCN or similar diagnoses before and after the introduction of TBSRTC. The pathology database at our institution identified all SFN/HCN or similar diagnoses in the 8 years surrounding the introduction of TBSRTC, and those cases were correlated with the surgical follow-up.

RESULTS

In the meta-analysis, the fraction of cases called SFN/HCN or the equivalent increased from 6.1 to 7.4% (p = 0.0002); the surgical follow-up rate increased from 55 to 61% (p < 0.00001), and the histological malignancy rate among the cases that were resected increased from 22 to 28% (p = 0.03) after TBSRTC. In our institutional experience, the introduction of TBSRTC did not coincide with any significant changes.

CONCLUSION

Standardized terminology clearly coincided with increases in follow-up and the malignancy rate of SFN/HCN. A change in the same statistics was not seen in our institutional experience.

Image reporting and characterization system for ultrasound features of thyroid nodules: multicentric Korean retrospective study

OBJECTIVE

The objective of this retrospective study was to develop and validate a simple diagnostic prediction model by using ultrasound (US) features of thyroid nodules obtained from multicenter retrospective data.

MATERIALS AND METHODS

Patient data were collected from 20 different institutions and the data included 2000 thyroid nodules from 1796 patients. For developing a diagnostic prediction model to estimate the malignant risk of thyroid nodules using suspicious malignant US features, we developed a training model in a subset of 1402 nodules from 1260 patients. Several suspicious malignant US features were evaluated to create the prediction model using a scoring tool. The scores for such US features were estimated by calculating odds ratios, and the risk score of malignancy for each thyroid nodule was defined as the sum of these individual scores. Later, we verified the usefulness of developed scoring system by applying into the remaining 598 nodules from 536 patients.

RESULTS

Among 2000 tumors, 1268 were benign and 732 were malignant. In our multiple regression analysis models, the following US features were statistically significant for malignant nodules when using the training data set: hypoechogenicity, marked hypoechogenicity, non-parallel orientation, microlobulated or spiculated margin, ill-defined margins, and microcalcifications. The malignancy rate was 7.3% in thyroid nodules that did not have suspicious-malignant features on US. Area under the receiver operating characteristic (ROC) curve was 0.867, which shows that the US risk score help predict thyroid malignancy well. In the test data set, the malignancy rates were 6.2% in thyroid nodules without malignant features on US. Area under the ROC curve of the test set was 0.872 when using the prediction model.

CONCLUSION

The predictor model using suspicious malignant US features may be helpful in risk stratification of thyroid nodules.

[MicroRNA profiles in fine needle biopsy of the thyroid]

MicroRNAs (miRNAs) are small (20-24 nucleotides), non-coding ribonucleid acids, which regulate gene expression on the post-transcriptional level, thus influencing physiological processes including cellular growth, differentiation and apoptosis. Several miRNAs (e. g. miRNAs 146b, 221 and 222) have been shown to be consistently over-expressed in papillary thyroid carcinoma. The present overview describes and discusses the utilization and problems of miRNA analysis in material from thyroid nodules obtained by fine needle biopsy. Particularly the analysis of defined sets of miRNAs should improve the diagnostic value of this procedure and contribute to a better management of patients with cold thyroid nodules.

The influence of fine-needle aspiration biopsy of the thyroid gland on the size of the examined nodule and its ultrasound image

INTRODUCTION

The aim of the study was to assess the influence of thyroid fine-needle aspiration biopsy (FNAB) on the size and ultrasound (US) features of the lesions and to examine whether the possible effects are persistent.

MATERIAL AND METHODS

One hundred and fifty biopsied and 50 control thyroid nodules underwent two US examinations, 10-20 days and 8-10 weeks after the biopsy. The study took into account lesion volume alterations, both absolute and relative (with reference to its initial value), and the presence of US features of malignancy: hypoechogenicity, microcalcifications, internal blood flow, irregular or blurred margins and suspicious shape of the lesions. The analysis covered only those nodules which immediately after FNAB did not change their appearance owing to cyst fluid evacuation or intranodular hemorrhage.

RESULTS

The increase of the lesion volume was more frequent in the group of biopsied lesions than the control one (58.0% vs. 24.0%, p < 0.0001) with the highest increase of 61.5%. The mean change percentage, however, was determined below 5% and a tendency of the lesions to resume their initial volume was noticeable. Neither a persistent increase in nodule volume of above 50% nor significant changes in the presence of malignancy suggestive US features were observed after FNAB. None of the biopsied nodules developed any microcalcifications, irregular or blurred margins, internal blood flow, or suspicious shape.

CONCLUSIONS

Fine-needle aspiration biopsy does not cause permanent changes in the US image of biopsied lesions, provided that the sampling technique is appropriate and there are no significant changes observed during the biopsy.

Virtual touch tissue quantification of acoustic radiation force impulse: a new ultrasound elastic imaging in the diagnosis of thyroid nodules

Objective

Virtual touch tissue quantification (VTQ) of acoustic radiation force impulse (ARFI) is a new quantitative technique to measure tissue stiffness. The study was aimed to assess the usefulness of VTQ in the diagnosis of thyroid nodules.

Methods

173 pathologically proven thyroid nodules in 142 patients were included and all were examined by conventional ultrasound (US), conventional elasticity imaging (EI) and VTQ of ARFI. The tissue stiffness for VTQ was expressed as shear wave velocity (SWV) (m/s). Receiver-operating characteristic curve (ROC) analyses were performed to assess the diagnostic performance. Intra- and inter-observer reproducibility of VTQ measurement was assessed.

Results

The SWVs of benign and malignant thyroid nodules were 2.34±1.17 m/s (range: 0.61–9.00 m/s) and 4.82±2.53 m/s (range: 2.32–9.00 m/s) respectively (P<0.001). The mean SWV ratios between each nodule and the adjacent thyroid tissue were 1.19±0.67 (range: 0.31–6.87) for benign and 2.50±1.54 (range: 0.85–6.69) for malignant nodules (P<0.001). ROC analyses indicated that the area under the curve was 0.861 (95% CI : 0.804, 0.918) (P<0.001) for SWV and 0.831(95% CI : 0.761, 0.900)(P<0.001) for the SWV ratio. The cutoff points for the differential diagnosis were 2.87 m/s for SWV and 1.59 for SWV ratio. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for EI were 65.9%, 66.7%, 66.5%, 40.3%, and 85.1%, respectively, and were 63.6%–75%, 82.2%–88.4%, 80.3%–82.1%, 58.9%–65.1%, and 87.7%–90.5%, respectively, for VTQ. The diagnostic value of VTQ is the highest for nodules >20 mm and lowest for those ≤10 mm. The correlation coefficients were 0.904 for intraobserver measurement and 0.864 for interobserver measurement.

Conclusions

VTQ of ARFI provides quantitative and reproducible information about the tissue stiffness, which is useful for the differentiation between benign and malignant thyroid nodules. The diagnostic performance of VTQ is higher than that of conventional EI.

Clinical-pathological changes in differentiated thyroid cancer (DTC) over time (1997-2010): data from the University Hospital "Maggiore della Carità" in Novara

Differentiated thyroid cancer (DTC) is an important clinical entity in our population (Novara, Piedmont, Italy) which is characterized by important environmental influences, as iodine deficiency (ID) and subsequent supplementation, thyroiditis and occupational exposure. To evaluate the features of DTC in our population 20 years after the iodine-prophylaxis pondering the effects of the introduction of the new guidelines for diagnosis and management of DTC after 2005. 322 patients [244 females, age: mean (±SD) 53.8 ± 15.8 years] treated for DTC in a tertiary care center between 1997 and 2010 were retrospectively evaluated. Medical history, demographics, and pathological features were considered. Patients were subdivided into two groups: A (n = 139, diagnosis 1997–2005) and B (n = 183, diagnosis 2006–2010). The population of group A showed a mild ID, while normal iodine status was recorded in group B. A significant increase in histological tumor-associated thyroiditis was found from group A to B (p = 0.021). Recurrent or persistent diseases were found to be correlated with lymph nodes metastases and/or a distant disease at diagnosis, stimulated thyroglobulin levels at the first follow-up and an additional radioiodine therapy. Twenty percent of our patients were females employed in textile industries. The tumor-related inflammation and the occupational exposure should be considered as important factors in the pathogenesis of DTC. Further studies are required in order to confirm our findings.

Acoustic radiation force impulse imaging for differentiation of thyroid nodules

BACKGROUND

Acoustic Radiation Force Impulse (ARFI)-Imaging is an ultrasound-based elastography method enabling quantitative measurement of tissue stiffness. The aim of the present study was to evaluate sensitivity and specificity of ARFI-imaging for differentiation of thyroid nodules and to compare it to the well evaluated qualitative real-time elastography (RTE).

METHODS

ARFI-imaging involves the mechanical excitation of tissue using acoustic pulses to generate localized displacements resulting in shear-wave propagation which is tracked using correlation-based methods and recorded in m/s. Inclusion criteria were: nodules ≥5 mm, and cytological/histological assessment. All patients received conventional ultrasound, real-time elastography (RTE) and ARFI-imaging.

RESULTS

One-hundred-fifty-eight nodules in 138 patients were available for analysis. One-hundred-thirty-seven nodules were benign on cytology/histology, and twenty-one nodules were malignant. The median velocity of ARFI-imaging in the healthy thyroid tissue, as well as in benign and malignant thyroid nodules was 1.76 m/s, 1.90 m/s, and 2.69 m/s, respectively. While no significant difference in median velocity was found between healthy thyroid tissue and benign thyroid nodules, a significant difference was found between malignant thyroid nodules on the one hand and healthy thyroid tissue (p = 0.0019) or benign thyroid nodules (p = 0.0039) on the other hand. No significant difference of diagnostic accuracy for the diagnosis of malignant thyroid nodules was found between RTE and ARFI-imaging (0.74 vs. 0.69, p = 0.54). The combination of RTE with ARFI did not improve diagnostic accuracy.

CONCLUSIONS

ARFI can be used as an additional tool in the diagnostic work up of thyroid nodules with high negative predictive value and comparable results to RTE.

Partially cystic thyroid nodules: ultrasound findings of malignancy

Objective

To seek for the ultrasound (US) findings of partially cystic thyroid nodules that are associated with malignancy.

Materials and Methods

We reviewed the US characteristics of 22 surgically confirmed partially cystic papillary carcinomas, and compared them with those of 80 benign partially cystic nodules. The review cases were selected in a random order from a total of 1029 partially cystic nodules that were diagnosed with an US-guided fine needle aspiration biopsy over a period of 8 years (June 2003 to October 2010) at our institution.

Results

In partially cystic thyroid nodules, a taller-than-wide shape (100%, p < 0.001) and spiculated or microlobulated margin (58.3%, p = 0.003) were significantly associated with malignancy. In terms of internal solid portion of the nodule, eccentric configuration (68.0%, p < 0.001), non-smooth margin (81.3%, p < 0.001), hypoechogenecity (30.0%, p < 0.042), and microcalcification (89.5%, p < 0.001) were more frequently demonstrated in malignant nodules than benign ones.

Conclusion

In partially cystic thyroid nodules, understanding the characteristics of US findings is important to make a precise diagnosis of malignant nodules.

Prestimulation with recombinant human thyrotropin (rhTSH) improves the long-term outcome of radioiodine therapy for multinodular nontoxic goiter

OBJECTIVE

The objective of the study was to evaluate the long-term outcome of recombinant human TSH (rhTSH)-augmented radioiodine ((131)I) therapy for benign multinodular nontoxic goiter.

PATIENTS AND METHODS

Between 2002 and 2005, 86 patients with a multinodular nontoxic goiter were treated with (131)I in two randomized, double-blind, placebo-controlled trials. (131)I-therapy was preceded by 0.3 mg rhTSH (n = 42) or placebo (n = 44). In 2009, 80 patients completed a follow-up (FU) visit, including determination of thyroid volume, thyroid function, and patient satisfaction by a visual analog scale.

RESULTS

In both groups, thyroid volume was further reduced from 1 yr to final FU (71 months). The mean goiter volume reductions obtained at 1 yr and final FU [59.2 ± 2.4% (sem) and 69.7 ± 3.1%, respectively] in the rhTSH group were significantly greater than those obtained in the (131)I-alone group (43.2 ± 3.7 and 56.2 ± 3.6%, respectively, P = 0.001 and P = 0.006), corresponding to a gain of 24% at final FU. At last FU the mean reduction in compression visual analog scale score was significantly greater in patients receiving rhTSH (P = 0.049). Additional therapy (thyroid surgery or (131)I) was required more often in the placebo group (nine of 44) compared with the rhTSH group (two of 42) (P = 0.05). The prevalence of hypothyroidism at 1 yr [9 and 43% in the placebo and rhTSH groups, respectively (P < 0.0001)] increased to 16 and 52%, respectively, at final FU (P = 0.001).

CONCLUSION

Enhanced goiter volume reduction with rhTSH-augmented (131)I therapy improves the long-term reduction in goiter-related symptoms and reduces the need for additional therapy compared with plain (131)I therapy. Overall patient satisfaction is benefited, despite a higher rate of permanent hypothyroidism.

Correlation of TSH with the risk of paediatric thyroid carcinoma

OBJECTIVE

Risk factors for the rare and unique entity of paediatric thyroid cancer are becoming more clearly defined. This study investigated the association of thyroid-stimulating hormone (TSH) with the diagnosis of differentiated thyroid carcinoma in the paediatric population. No previous studies have correlated the paediatric thyroid cancer risk with TSH levels.

DESIGN

Retrospective case-controlled study.

PATIENTS

A total of 116 paediatric patients with an indication for thyroidectomy referred to Seattle Children's Hospital, a major paediatric tertiary medical centre, between January 1997 and January 2011 were assessed. Excluding confounders that would directly affect TSH values, 78 patients (29 patients with and 49 patients without thyroid cancer) between the ages of 3 and 20 years were evaluated.

MEASUREMENTS

Preoperative TSH values correlated with pathology review of en bloc resected thyroid tissue specimens.

RESULTS

The diagnosis of paediatric thyroid carcinoma was significantly associated with elevated TSH levels. The average TSH level (2·32 ± 0·51 mIU/l) was significantly greater than the TSH level (1·08 ± 0·14 mIU/l) noted in patients without malignancy (P = 0·03). A rightward skew of TSH was associated with paediatric patients harbouring paediatric thyroid carcinoma, with a TSH level ≥2·50 mIU/l correlating with a significantly increased odds ratio of thyroid cancer (OR 8·05, 95% CI 1·41-81·39, P = 0·0073) relative to a normal TSH range of 0·40-2·49 mIU/l.

CONCLUSIONS

Paediatric thyroid carcinoma is associated with TSH level ≥ 2·50 mIU/l, which may be useful to identify a higher risk of malignancy in a paediatric patient with a thyroid nodule.

The role of nuclear medicine in differentiated thyroid cancer

In differentiated thyroid cancer (DTC) nuclear medicine is able to cover the spectrum from diagnosis and treatment to follow up keeping patient's management in one institution. Nowadays, DTC is often diagnosed per chance, presenting as small indolent nodule diagnosed on routinely performed ultrasound. Ultrasound and ultrasonography-guided fine-needle aspiration biopsy together with scintigraphy are probably the most adequate tools for diagnosis. After thyroidectomy, treatment with iodine-131 is routinely performed in a nuclear medicine therapy institution as a standard procedure in most of the cases with regard to histology. In case of iodine positive metastases, repeated therapies can be performed in order to reduce tumour burden. In the follow up of DTC thyroglobulin (tumour marker), ultrasound and diagnostic whole body scan are established procedures. With the development of SPECT/CT and PET/CT ((18)F-FDG, (68)Ga-somatostatin receptor) combining functional and anatomic imaging the nuclear medicine spectrum has further increased.

Mixed echoic thyroid nodules on ultrasound: approach to management

PURPOSE

To evaluate malignancy risk according to ultrasound (US) features and size change on follow-up US in mixed echoic thyroid nodules and to suggest management guidelines thereof.

MATERIALS AND METHODS

Among patients who underwent US-guided fine needle aspiration biopsy, 316 mixed echoic nodules in 303 patients were included after excluding the patients with pure solid or cystic nodules or without further cytopathologic evaluation. We evaluated malignancy risk according to US features and changes in size and shape on follow-up US.

RESULTS

The malignancy rate was 31.6% (6 of 19) for nodules with suspicious US features and 2.7% (8 of 297) for nodules without suspicious US features (p<0.001). Among 265 nodules with no suspicious US features and initial benign cytology, 15 nodules with suspicious US change and decreased size, 25 nodules with no suspicious US change and increased size, and 225 nodules with no suspicious US change and no change in size were observed on follow-up USs. The malignancy risk thereof was 0%, 0% and 0.4%, respectively (p=1.000).

CONCLUSION

Mixed echoic nodules with no suspicious US features and benign cytology can be followed up using US, as they revealed very low malignancy rates, even if they showed growth on follow-up US.

A high-resolution melting protocol for rapid and accurate differential diagnosis of thyroid nodules

A large majority of thyroid nodules are benign, and only 5% have malignant features on cytological examination. Unfortunately, fine-needle aspiration is inconclusive in approximately 30% of all thyroid biopsies, because the cytological features are indeterminate (suspicious for malignancy but not completely diagnostic or nondiagnostic). Wide panels of somatic mutations have been identified in thyroid cancers, and detection of genetic alterations in fine-needle aspirate has been demonstrated to improve diagnostic accuracy. Nevertheless, the relatively high number of genetic targets to be investigated, in comparison with the low percentage of malignant samples, makes the usual diagnostic protocol both time-consuming and expensive. We developed a reliable and sensitive protocol based on high-resolution melting analysis for the rapid screening of mutations of KRAS, HRAS, NRAS, and BRAF oncogenes in thyroid fine-needle aspirations. The entire procedure can be completed in approximately 48 hours, with a dramatic reduction in costs. The proposed protocol was applied to the analysis of 260 consecutive fine-needle aspiration biopsy (FNAB) samples. In 35 of 252 samples, 36 sequence variants were detected for BRAF (17 samples), NRAS (6 samples), HRAS (3 samples), KRAS codon 12 (9 samples), and KRAS codon 61 (1 sample).

Pathological findings of thyroid nodules after percutaneous laser ablation : a series of 22 cases with cyto-histological correlation

Ultrasound (US)-guided percutaneous laser ablation (LA) of benign thyroid nodules may be a potential alternative to surgery in patients with compressive symptoms, at high surgical risk, or in patients who refuse to undergo surgery. We evaluated the morphological effects of LA procedure on 22 patients and compared the cytological findings before and after LA with the histological features on surgical specimens. Twenty-two (4.9%; 19 women, three men, mean age 53.2 years) out of 452 patients treated with LA for benign thyroid nodules in our Hospital underwent surgery after LA procedure, either because nodule regrowth (treatment failure, n = 17) or indeterminate cytology (Thy3) after LA (n = 5). Morphological findings varied according to the time between LA and surgical intervention. Within 2 months, the area was occasionally cavitated and filled in with dark amorphous material. The inflammatory response was abundant and composed of neutrophils, lymphocytes, and macrophages. After 18 months or more since LA, the expected laser-induced histologic changes in thyroid morphology consisted of a well-defined area surrounded by a fibrous capsule and filled in by amorphous material. No significant pathologic features were found in the thyroid tissue adjacent to the treated area. Histological evaluation of thyroid tissues after LA shows that thermal damage is restricted to the ablated area, with no involvement of the nearby parenchyma. Our long-term histopathological findings indicate that LA treatment of benign thyroid nodules is safe, and patients undergoing LA may also be followed up by fine needle aspiration.

Ultrasound guided fine-needle aspiration biopsy of thyroid nodules: Guidelines and recommendations vs clinical practice; a 12-month study of 89 patients

INTRODUCTION

Given the high prevalence of thyroid nodules in the general population it is essential to develop a method for identifying those nodules which require fine-needle aspiration biopsy (FNAB) due to suspicion for malignancy in order to avoid over- or under treatment of this disease. The ultrasound (US) criteria identified by Kim et al. and the American Association of Clinical Endocrinologists appear to be the most sensitive and most specific. The purpose of this study was to analyze a sample of patients who underwent FNAB of the thyroid and to compare the obtained data with the international guidelines and the recommendations for management of thyroid nodules.

MATERIALS AND METHODS

This study analyzed the clinical, anamnestic and US reasons for which 97 nodules located in 89 patients underwent FNAB, and the data were compared with the criteria set by the guidelines and with the cytological results.

RESULTS

Echogenicity was indication for FNAB in 99% of cases, appearance of the margins in 75.3%, presence of calcifications in 93.8% and presence of vascularity in 73.2%. In a total of 4.1% of cases, cytological outcome was positive for malignancy, 21.6% necessitated monitoring, 4.1% were referred to surgery and histological examination of the surgical specimen and 63.9% resulted negative for malignancy.

DISCUSSION

The finding of hypoechoic nodules often leads to continued investigation; the presence of intranodular vascularization detected at Doppler US is perceived as suspicious and the presence of microcalcifications always leads to further investigation. On the request of the endocrinologist the dominant nodule in a goiter is in most cases subjected to FNAB even if the volume has not increased. Adequate US criteria can help identify potentially malignant nodules and guide implementation of FNAB. However, identification of malignant nodules using instrumental investigation cannot disregard medical records and clinical laboratory tests. According to the authors' experience, a close collaboration between endocrinologists, radiologists and pathologists is essential for a correct evaluation of patients with thyroid nodules in order to avoid over or under estimation of the risk of malignancy of a nodule and therefore of the necessity to perform further examinations.

Ultrasound-guided percutaneous thyroid nodule core biopsy: clinical utility in patients with prior nondiagnostic fine-needle aspirate

BACKGROUND

Five percent to 20% of thyroid nodule fine-needle aspiration (FNA) samples are nondiagnostic. The objective of this study was to determine whether a combination of FNA and core biopsy (CFNACB) would yield a higher proportion of diagnostic readings compared with FNA alone in patients with a history of one or more prior nondiagnostic FNA readings.

METHODS

We conducted a retrospective study of 90 core biopsies (CBs) performed in 82 subjects (55 women and 27 men) between 2006 and 2008 in an outpatient clinic.

RESULTS

CFNACB yielded a diagnostic reading in 87%. The diagnostic reading yield of the CB component of CFNACB was significantly superior to the concurrent FNA component, with CB yielding a diagnosis in 77% of cases and FNA yielding a diagnosis in 47% (p<0.0001). The combination of CB and FNA had a higher diagnostic reading yield than either alone. In 69 nodules that had only one prior nondiagnostic FNA, CB was diagnostic in 74%, FNA was diagnostic in 52%, CFNACB was diagnostic in 87%, and CB performed significantly better than FNA (p=0.0135). In 21 nodules with two or more prior nondiagnostic FNAs, CFNACB and CB were diagnostic in 86%, FNA was diagnostic in 29%, and CB was significantly better than FNA (p=0.0005). Clinical, ultrasound, or histopathologic follow-up was available for 81% (73/90) of the CFNACB procedures. No subject with a benign CFNACB reading was diagnosed with thyroid malignancy in the follow-up period (range 4-37 months, mean 18 months), although one subject had minimal increase in nodule size and was awaiting repeat sonography at study conclusion.

CONCLUSION

Thyroid nodule CFNACB is safe and clinically useful in selected patients when a prior FNA reading is nondiagnostic. CFNACB is superior to either CB or FNA alone. CFNACB should be strongly considered as an alternative to surgery in individuals with two prior nondiagnostic FNAs.

A case of autoimmune hepatitis and bisphosphonate-related osteonecrosis of the jaw

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease of unknown aetiology usually requiring long-term immunosuppressive therapy. We present the case of an AIH patient who received long-term corticosteroids and azathioprine. As treatment for concomitant osteoporosis she was also treated with potent intravenous bisphosphonate (BP). This treatment was complicated by the development of BP-related osteonecrosis of the jaw (BRONJ). BRONJ is an uncommon complication of BP treatment regimes that occurs at increased frequency in the presence of other risk factors, including chronic inflammatory conditions. Our patient suffered from a severe and complicated clinical course of BRONJ which, despite adequate therapy, resulted in death of the patient. Here we discuss the risk factors for the development and clinical course of BRONJ in AIH and the implications for management of these patients.

American Thyroid Association consensus review and statement regarding the anatomy, terminology, and rationale for lateral neck dissection in differentiated thyroid cancer

BACKGROUND

Cervical lymph node metastases from differentiated thyroid cancer (DTC) are common. Thirty to eighty percent of patients with papillary thyroid cancer harbor lymph node metastases, with the central neck being the most common compartment involved. The goals of this study were to: (1) identify appropriate methods for determining metastatic DTC in the lateral neck and (2) address the extent of lymph node dissection for the lateral neck necessary to control nodal disease balanced against known risks of surgery.

METHODS

A literature review followed by formulation of a consensus statement was performed.

RESULTS

Four proposals regarding management of the lateral neck are made for consideration by organizations developing management guidelines for patients with thyroid nodules and DTC including the next iteration of management guidelines developed by the American Thyroid Association (ATA). Metastases to lateral neck nodes must be considered in the evaluation of the newly diagnosed thyroid cancer patient and for surveillance of the previously treated DTC patient.

CONCLUSIONS

Lateral neck lymph nodes are a significant consideration in the surgical management of patients with DTC. When current guidelines formulated by the ATA and by other international medical societies are followed, initial evaluation of the DTC patient with ultrasound (or other modalities when indicated) will help to identify lateral neck lymph nodes of concern. These findings should be addressed using fine-needle aspiration biopsy. A comprehensive neck dissection of at least nodal levels IIa, III, IV, and Vb should be performed when indicated to optimize disease control.

Diagnostic performance of gray-scale US and elastography in solid thyroid nodules

PURPOSE

To evaluate the diagnostic performance of gray-scale ultrasonography (US) and elastography in differentiating benign and malignant thyroid nodules.

MATERIALS AND METHODS

This was an institutional review board-approved retrospective study with waiver of informed consent. A total of 703 solid thyroid nodules in 676 patients (mean age, 49.7 years; range, 18-79 years) were included; there were 556 women (mean age, 49.5 years; range, 20-74 years) and 120 men (mean age, 50.7 years; range, 18-79 years). Nodules with marked hypoechogenicity, poorly defined margins, microcalcifications, and a taller-than-wide shape were classified as suspicious at grayscale US. Findings at elastography were classified according to the Rago criteria and the Asteria criteria. The diagnostic performances of gray-scale US and elastography were compared. For comparison between the diagnostic performances of gray-scale US and the combination of gray-scale US and elastography, three sets of criteria were assigned: criteria set 1, nodules with any suspicious grayscale US feature were assessed as suspicious; criteria set 2, Rago criteria were added as suspicious features to criteria set 1; and criteria set 3, Asteria criteria were added as suspicious features to criteria set 1. The diagnostic performances of gray-scale US, elastography with Rago criteria, and elastography with Asteria criteria, and odds ratios (ORs) with 95% confidence intervals for predicting thyroid malignancy were compared using generalized estimating equation analysis.

RESULTS

Of 703 nodules, 217 were malignant and 486 were benign. Sensitivity, negative predictive value (NPV), and OR of gray-scale US for the 703 nodules were 91.7%, 94.7%, and 22.1, respectively, and these values were higher than the 15.7% and 65.4% sensitivity, 71.7% and 79.1% NPV, and 3.7 and 2.6 ORs found for elastography with Rago and Asteria criteria, respectively. Specificity, positive predictive value, and accuracy for criteria set 1 were significantly higher than those for criteria sets 2 and 3 for most of the nodule subgroups that were considered.

CONCLUSION

Elastography alone, as well as the combination of elastography and gray-scale US, showed inferior performance in the differentiation of malignant and benign thyroid nodules compared with gray-scale US features; elastography was not a useful tool in recommending fine-needle aspiration biopsy.

Prevalence of malignancy in thyroid nodules with an initial nondiagnostic result after ultrasound guided fine needle aspiration

The objective of this study was to determine the rate of malignancy in thyroid nodules with an initial nondiagnostic fine needle aspiration. From October 2001 to April 2007, biopsies were performed on 1344 thyroid nodules in our practice. Biopsies were performed on nodules using 25-27 gauge needles, ultrasound guidance and multiple passes using both suction and capillary action. We retrospectively reviewed the results of these biopsies as well as any further management of nodules that received nondiagnostic results (IRB HUM00006459). Following initial biopsy, 295/1344 (21.9%) of nodules received nondiagnostic pathologic results. Of this population, 39 nodules (13.1%) were lost to follow-up. Of the remaining 256 nodules that received a repeat FNA, surgical excision, or greater than 24 months of clinical and imaging follow-up, only five cancers were detected, representing only 2% of the population that received an initial nondiagnostic biopsy result. All of these cancers were papillary neoplasms. When rigorous, ultrasound-guided, fine needle aspiration of thyroid nodules is performed, a nondiagnostic histopathologic result should not be interpreted as suspicious for thyroid cancer. Given the low rate of malignancy in this population (2%), we suggest that clinical and imaging follow-up of these nodules, opposed to repeat sampling, is warranted.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

KEY POINTS

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

Radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: consensus statement and recommendations

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 has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus.

Clinical implication of elastography as a prognostic factor of papillary thyroid microcarcinoma

BACKGROUND

A firm and hard thyroid nodule on palpation is known to be associated with an increased risk of thyroid malignancy. Elastography has been introduced to evaluate the tissue hardness objectively. We investigated the clinical implications of elastography as a prognostic factor in patients with papillary thyroid microcarcinoma.

METHODS

Elastography images were classified according to Rago scores of 1-5. Malignancies with Rago scores of 4 or 5 were considered as "hard" and remaining malignancies as "soft." Clinicopathologic characteristics were compared between patients with hard or soft malignancies according to the extrathyroidal extension and central and lateral lymph node metastasis by using chi-square tests, Fisher's exact test, and independent t tests. Odds ratios with 95% confidence intervals were calculated for evaluating the factors for predicting extrathyroidal extension and central and lateral lymph node metastasis.

RESULTS

A hard malignancy on the Rago score was significantly associated with pathologic extrathyroidal extension compared with a soft malignancy (P=0.001). The odds ratio of a hard malignancy on the Rago score for predicting extrathyroidal extension was 5.060 (95% confidence interval, 1.565-16.358). A hard malignancy on Rago scores was not associated with central or lateral lymph node metastasis.

CONCLUSIONS

A hard malignancy on the Rago score of elastography was an independent factor for predicting pathologic extrathyroidal extension on pathology.

Positron emission tomography/computed tomography in patients treated for differentiated thyroid carcinomas

Differentiated thyroid cancer (DTC) generally has a favorable prognosis; however, the chance of a recurrence in patients with DTC is 20%, and 8% of patients with recurrence will subsequently die of the disease. After thyroid remnant ablation, detectable serum thyroglobulin levels are a sensitive marker for residual or recurrent disease, while imaging procedures, primarily neck ultrasound and an iodine-131 (¹³¹I) or iodine-123 diagnostic whole-body scan, are useful to localize recurrent disease. However, ultrasound cannot identify lesions outside the neck, and diagnostic whole-body scan is of limited value if progressive dedifferentiation of thyroid carcinoma cells occurs. In these patients, fluorine-18 (¹⁸F)-fluorodeoxyglucose PET/computed tomography (¹⁸FDG-PET/CT) has been shown to improve detection and localization of tumor foci. Additionally, ¹⁸FDG-PET/CT is also of value in selecting patients unlikely to benefit from additional ¹³¹I therapy and those at highest risk of disease-specific mortality, which may prompt more alternative therapies. Recently, iodine-124 (¹²⁴I)-PET/CT was proved to perform better than low-dose diagnostic ¹³¹I scans. Additionally, ¹²⁴I PET/CT succesfully predicts the results of subsequent high-dose post-treatment ¹³¹I scans and allows lesion-based dosimetric calculations. The present article reviews the utility and limitations of PET/CT techniques in DTC management and offers practical recommendations.

Thyroid nodules: risk stratification for malignancy with ultrasound and guided biopsy

Replacing palpating fingers with an ultrasound (US) probe has resulted in an epidemic of thyroid nodules. Despite the high prevalence of thyroid nodules in the general population, thyroid malignancy is rare. Although no imaging modality can accurately predict the nature of every nodule, high-resolution US is the most sensitive, easily available and cost-effective diagnostic test available to detect thyroid nodules, measure their dimensions and identify their structure. The presence of calcifications, irregular spiculated outline, hypoechogenicity in a solid nodule, chaotic intranodular vascularity and an elongated shape are well-known US features of malignancy in thyroid nodules. Cervical lymph node metastasis and extrathyroidal extension of a thyroid nodule are highly specific for malignancy but seen infrequently. Spongiform nodules, purely or predominantly cystic nodules, nodules with well-defined hypoechoic halo and echogenic as well as isoechoic nodules are usually benign. None of the US characteristics have 100% accuracy in detecting or excluding malignancy. Fine-needle biopsy is currently the best triage test for pre-operative evaluation of a thyroid nodule. There is no significant difference in the risk for malignancy between palpable and non-palpable nodules and size is not a reliable indicator for their malignant potential. The best tool for risk stratification for malignancy in thyroid nodules is US and guided biopsy of nodules with suspicious imaging features. This is especially relevant in patients with multinodular goitre.

Hypothyroidism among former workers of a nuclear weapons facility

BACKGROUND

Ionizing radiation alters thyroid function, and workers at a nuclear weapons facility may be exposed to above environmental levels of radiation.

METHODS

Hypothyroid status was determined for 622 former workers of a nuclear weapons facility located in Texas, using a combination of measured thyroid stimulating hormone (TSH) levels and thyroid medication history, as part of an on-going health surveillance program. We classified 916 unique job titles into 35 job categories.

RESULTS

According to the most stringent TSH definition used in this study (0.3-3.0 IU/ml), 174 (28.0%) former workers were considered to be hypothyroid; of these 66 (41.8%) were females and 108 (23.3%) were males. In logistic regression analysis adjusted for age, gender, and smoking status, only having worked as a material handler (n = 18) exhibited an elevated risk of developing hypothyroidism compared to other jobs (OR 3.88, 95% CI 1.43-11.07). This is one of the jobs with suspected exposure to radiation. No excess risk of hypothyroidism was observed for any of the other job categories.

CONCLUSIONS

There is suggestive evidence that only material handlers at this nuclear weapons facility may have elevated risk of hypothyroidism; further evaluation of thyroid health in this population is warranted.

Thyroid disorders in pregnancy

Maternal hypothyroidism, thyroid antibody positivity, and hyperthyroidism may pose significant risks in terms of pregnancy complications and fetal adverse effects. Treatment of hyperthyroidism with thionamides remains the standard of care during pregnancy. Radioiodine use is contraindicated in pregnancy, including in the treatment of thyroid carcinoma, because of the risk of fetal hypothyroidism, subsequent cognitive impairment, and even fetal death. Normal thyroid function during pregnancy is essential to ensure delivery, to the best extent possible, of a healthy baby, which may be achieved with frequent monitoring of thyroid function during gestation and cautious adjustment of medications during treatment.

Screening for medullary thyroid carcinoma with serum calcitonin measurements in patients with thyroid nodules in the United States and Canada

BACKGROUND

Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy with the potential for aggressive behavior. Measurement of serum calcitonin (Ct) in the thyroid nodule population is the most sensitive way to detect occult MTC. An important and controversial question is whether all patients with thyroid nodules should undergo Ct measurements to detect occult MTC.

SUMMARY

The prevalence of MTC detected by performing surgery on unselected individuals with thyroid nodules with elevated serum Ct is 0.4%. The central role of pentagastrin (PG) stimulation for triaging patients with minimally elevated serum Ct to prevent unnecessary surgery is reviewed. Data concerning a large reservoir of medullary thyroid microcarcinomas are discussed.

CONCLUSION

Given the unavailability of PG in the United States and Canada, the available data argue against routine Ct measurements in all individuals with thyroid nodules in these countries because of the potential for unnecessary surgery and the uncertain benefit in diagnosing medullary microcarcinoma.

Immunocytochemistry with cytokeratin 19 and anti-human mesothelial cell antibody (HBME1) increases the diagnostic accuracy of thyroid fine-needle aspirations: preliminary report of 150 liquid-based fine-needle aspirations with histological control

BACKGROUND

Thyroid nodules are relatively common (7% of the population) but are malignant in only 5%-10% of cases. Fine-needle aspiration (FNA) to detect cancer can have > 90% sensitivity but only 50%-65% specificity because of false-positive results, which necessitates surgical controls. We aimed to assess the diagnostic accuracy of immunocytochemistry (ICC) of thyroid FNA to improve its sensitivity and specificity.

METHODS

We prospectively collected 2038 thyroid FNAs, of which 1397 were FNA biopsies with liquid-based cytology (Thin-Prep-Hologic®). ICC with cytokeratin 19 and HBME1 antibodies (Dako® A/S) was used for all malignant cases and cases of atypical cells of undetermined significance (AUS), follicular neoplasm (FN), and nodules suspicious for malignancy-papillary thyroid carcinoma (SM-PTC) as well as some benign cases (abnormal features on radiography or benign on secondary FNA). ICC results were defined as "non-contributory," "favoring benign," "favoring malignant," or "indeterminate." Results for 150 cases were compared with histological controls for diagnostic accuracy.

RESULTS

Of these 150 cases ICC was helpful for benign or malignant triage of 48 cases of AUS, FN, and SM-PTC (42% of these lesions). Six (4%) ICC results were false positive (favoring malignant with benign histology) but none were false negative (favoring benign with malignant histology). Results for indeterminate cytological cases favored malignant or benign disease with sensitivity, specificity, and negative and positive predictive values of 100%, 85.2%, 100%, and 86.2%, respectively.

CONCLUSIONS

ICC of thyroid FNAs with cytokeratin 19 and HBME1 antibodies can reduce the false-positive and false-negative results of single morphological analyses. It can increase the sensitivity and specificity of diagnosis, thus improving diagnostic accuracy and reducing the need for surgical controls.