Solitary thyroid nodule. Comparison between palpation and ultrasonography

Approach to Thyroid Nodules: Diagnosis and Treatment

Thyroid nodules (TNs) are prevalent and found in up to 50% of individuals. While most TNs are benign, some can be malignant. The evaluation of TNs is crucial to rule out malignancy and identify those requiring surgical intervention. This study aimed to clarify the reported prevalence of TNs, focusing specifically on their various types, assessment and diagnostic processes, current evaluation methods, and evidence-based management. It also provides recommendations for follow-up. TNs are typically found during physical exams or incidentally during imaging procedures. Routine laboratory and clinical evaluations of TNs are common. Ultrasound is the preferred imaging method to determine if a TN needs a biopsy. Fine-needle aspiration (FNA) is crucial in deciding whether surgery or surveillance is necessary. TNs that show suspicious features on the ultrasound may require cytologic analysis to assess the risk of malignancy. The effectiveness of several supplementary molecular tests is still uncertain, although some studies report promising results. The management and treatment approach for TNs primarily depends on the results of FNA cytology and ultrasound characteristics. The optimal treatment strategy for TNs ranges from straightforward follow-ups for low-risk cases to surgical intervention for high-risk patients. Rather than adopting a uniform approach, clinicians should assess each patient on a case-by-case basis using current knowledge and a collaborative, multidisciplinary method.

The Role of Ultrasound, Scintigraphy, and Cytology in Evaluating Thyroid Nodules

Abstract Background: Thyroid function testing and imaging studies guide the initial management of thyroid nodules. Our study aims to assess the role that ultrasound (US) and scintigraphy play in thyroid nodules. Methods: We conducted a prospective case series study of 212 consecutive patients presented with thyroid nodules at the tertiary University Hospital of Tirana (“Mother Teresa”) for further evaluation between January 2018 and March 2018.  All patients were examined with US and scintigraphy with 99mTc and underwent fine- needle aspiration cytology. Generalized Linear Model (ordinal logistic) was used to predict the dependent variable with 'ordered' multiple categories and independent variables. Results: The majority of patients (85%) were female, and (15%) males, p<0.001. The ordered logit for US finding’s presence of microcalcifications, adenopathy, solid or solidcystic nodules, being in a higher TIR category was 1.27, 4.56, 2.70 and 1.70 more than absence of microcalcifications, adenopathy and cystic nodules, respectively. Conversely, a one unit (year) increase in age would result in a 0.035 unit decrease in the ordered log-odds of being in a higher TIR category.  For the scintigraphy findings, the ordered logit for isohypofunctional and hypofunctional nodules (vs. isofunctional), in a higher TIR category, was 1.70 and 2.10 higher, respectively. Conclusions: In thyroid glandular nodules, only a small percentage are malignant, therefore examination with ultrasound, scintigraphy and FNA are important to lower the number of patients undergoing surgery. Given the study's results, scintigraphy has a significant value, but in order to diagnose malignant nodules ultrasound remained an initial and important diagnostic tool, which, when combined with FNA, rounds out a clear diagnosis of thyroid nodules.

Standardisation of thyroid cytology terminology and practice: are modifications necessary?-a narrative review

Universally accepted guidelines for diagnosis and management of any disease are desirable. Standardization of thyroid cytology reporting is aimed at guiding and improving clinical decision-making and management. However, socio-economic, and local factors and differences in disease prevalence and patterns require modification to suit local settings. 'One size fit all' approach is not possible for any disease diagnosis or management. The same concept is applicable in diagnosis and management of thyroid nodules. An additional special issue is the well-known high inter and intra-observer variability in the histological and cytological diagnosis of thyroid neoplasms. Despite this, thyroid cytology has a very significant influence in the management of thyroid diseases. An approach based on common principals with appropriate modifications that suits countries or continents is desirable and sustainable. The principals of TBSRTC have served as a framework for similar tiered classifications for reporting thyroid cytopathology. This article discusses globally available professional guidelines based on a common framework with appropriate modifications, with the universal aim of risk stratification of thyroid nodules.

Thyroid nodules and cancer during pregnancy, post-partum and preconception planning: Addressing the uncertainties and challenges

Thyroid nodules and thyroid cancer have become increasingly common worldwide. When discovered during pregnancy, they pose unique diagnostic and therapeutic challenges for both the treating physician and the patient. The benefits of treatment should be carefully weighed against risks that may adversely impact maternal and fetal health. In this review, we present current knowledge and controversies surrounding the management of thyroid nodules and thyroid cancer in pregnancy, in the post-partum period and during preconception planning.

CAD system based on B-mode and color Doppler sonographic features may predict if a thyroid nodule is hot or cold

OBJECTIVES

The aim of this study was to evaluate if the analysis of sonographic parameters could predict if a thyroid nodule was hot or cold.

METHODS

Overall, 102 thyroid nodules, including 51 hyperfunctioning (hot) and 51 hypofunctioning (cold) nodules, were evaluated in this study. Twelve sonographic features (i.e., seven B-mode and five Doppler features) were extracted for each nodule type. The isthmus thickness, nodule volume, echogenicity, margin, internal component, microcalcification, and halo sign features were obtained in the B-mode, while the vascularity pattern, resistive index (RI), peak systolic velocity, end diastolic velocity, and peak systolic/end diastolic velocity ratio (SDR) were determined, based on Doppler ultrasounds. All significant features were incorporated in the computer-aided diagnosis (CAD) system to classify hot and cold nodules.

RESULTS

Among all sonographic features, only isthmus thickness, nodule volume, echogenicity, RI, and SDR were significantly different between hot and cold nodules. Based on these features in the training dataset, the CAD system could classify hot and cold nodules with an area under the curve (AUC) of 0.898. Also, in the test dataset, hot and cold nodules were classified with an AUC of 0.833.

CONCLUSIONS

2D sonographic features could differentiate hot and cold thyroid nodules. The CAD system showed a great potential to achieve it automatically.

KEY POINTS

• Cold nodules represent higher volume (p = 0.005), isthmus thickness (p = 0.035), RI (p = 0.020), and SDR (p = 0.044) and appear hypoechogenic (p = 0.010) in US. • Nodule volume with an AUC of 0.685 and resistive index with an AUC of 0.628 showed the highest classification potential among all B-mode and Doppler features respectively. • The proposed CAD system could distinguish hot nodules from cold ones with an AUC of 0.833 (sensitivity 90.00%, specificity 70.00%, accuracy 80.00%, PPV 87.50%, and NPV 75.00%).

Real-Time Vision-Based Stiffness Mapping †

This paper presents new findings concerning a hand-held stiffness probe for the medical diagnosis of abnormalities during palpation of soft-tissue. Palpation is recognized by the medical community as an essential and low-cost method to detect and diagnose disease in soft-tissue. However, differences are often subtle and clinicians need to train for many years before they can conduct a reliable diagnosis. The probe presented here fills this gap providing a means to easily obtain stiffness values of soft tissue during a palpation procedure. Our stiffness sensor is equipped with a multi degree of freedom (DoF) Aurora magnetic tracker, allowing us to track and record the 3D position of the probe whilst examining a tissue area, and generate a 3D stiffness map in real-time. The stiffness probe was integrated in a robotic arm and tested in an artificial environment representing a good model of soft tissue organs; the results show that the sensor can accurately measure and map the stiffness of a silicon phantom embedded with areas of varying stiffness.

Thyroid nodule update on diagnosis and management

Thyroid nodules are common. The clinical importance of thyroid nodules is related to excluding malignancy (4.0 to 6.5% of all thyroid nodules), evaluate their functional status and assess for the presence of pressure symptoms. Incidental thyroid nodules are being diagnosed with increasing frequency in the recent years with the use of newer and highly sensitive imaging techniques. The high prevalence of thyroid nodules necessitates that the clinicians use evidence-based approaches for their assessment and management. New molecular tests have been developed to help with evaluation of malignancy in thyroid nodules. This review addresses advances in thyroid nodule evaluation, and their management considering the current guidelines and supporting evidence.

Striving toward standardization of reporting of ultrasound features of thyroid nodules and lymph nodes: a multidisciplinary consensus statement

BACKGROUND

The use of high-resolution ultrasound (US) imaging is a mainstay of the initial evaluation and long-term management of thyroid nodules and thyroid cancer. To fully capitalize on the diagnostic capabilities of a US examination in the context of thyroid disease, many clinicians consider it desirable to establish a universal format and standard of US reporting. The goals of this interdisciplinary consensus statement are twofold. First, to create a standardized set of US features to characterize thyroid nodules and cervical lymph nodes accurately, and second, to create a standardized system for tracking sequential changes in the US examination of thyroid nodules and cervical lymph nodes for the purpose of determining risk of malignancy.

SUMMARY

The Thyroid, Head and Neck Cancer (THANC) Foundation convened a panel of nine specialists from a variety of medical disciplines that are actively involved in the diagnosis and treatment of thyroid nodules and thyroid cancer. Consensus was achieved on the following topics: US evaluation of the thyroid gland, US evaluation of thyroid nodules, US evaluation of cervical lymph nodes, US-guided fine needle aspiration (FNA) of thyroid nodules, and US-guided FNA of cervical lymph nodes.

CONCLUSION

We propose that this statement represents a consensus within a multidisciplinary team on the salient and essential elements of a comprehensive and clinically significant thyroid and neck US report with regards to content, terminology, and organization. This reporting protocol supplements previous US performance guidelines by not only capturing categories of findings that may have important clinical implications, but also delineating findings that are clinically relevant within those categories as specifically as possible. Additionally, we have included the specific features of diagnostic and therapeutic interventions that have not been previously addressed.

Hyperfunction thyroid nodules: their risk for becoming or being associated with thyroid cancers

OBJECTIVE

To retrospectively evaluate the risk of thyroid cancer in patients with hyperfunctioning thyroid nodules through ultrasonographic-pathologic analysis.

MATERIALS AND METHODS

Institutional review board approval was obtained and informed consent was waived. From 2003 to 2007, 107 patients consecutively presented with hot spots on thyroid scans and low serum thyroid-stimulating hormone levels. Among them, 32 patients who had undergone thyroid ultrasonography were analyzed in this study. Thyroid nodules depicted on ultrasonography were classified based on size and categorized as benign, indeterminate, or suspicious malignant nodules according to ultrasonographic findings. The thyroid nodules were determined as either hyperfunctioning or coexisting nodules and were then correlated with pathologic results.

RESULTS

In 32 patients, 42 hyperfunctioning nodules (mean number per patient, 1.31; range, 1-6) were observed on thyroid scans and 68 coexisting nodules (mean, 2.13; range, 0-7) were observed on ultrasonography. Twenty-five patients (78.1%) had at least one hyperfunctioning (n = 17, 53.1%) or coexisting (n = 16, 50.0%) nodule that showed a suspicious malignant feature larger than 5 mm (n = 8, 25.0%), or an indeterminate feature 1 cm or greater (n = 20, 62.5%) in diameter, which could have been indicated by using fine needle aspiration (FNA). Seven patients were proven to have 11 thyroid cancers in 3 hyperfunctioning and 8 coexisting nodules. All of these had at least one thyroid cancer, which could have been indicated by using FNA. The estimated minimal risk of thyroid cancer was 6.5% (7/107).

CONCLUSION

Patients with hyperfunctioning nodules may not be safe from thyroid cancer because hyperfunctioning nodules can coexist with thyroid cancer nodules. To screen out these cancers, ultrasonography should be performed.

Thyroid incidentaloma

Because of emerging investigation modalities many of the thyroid lesions are picked up and that poses a big dilemma about management of such lesions. Majority of these lesions especially in iodine-deficient regions, are not significant and may be only followed up without any active treatment but, sometimes the small lesions may be microcarcinoma. This article discusses about the reliability of clinical examination of neck for detection of such lesions, the controversy of such lesion being benign or malignant, and how to evaluate these lesions and the recommendation as per American Thyroid Association guidelines.

Thyroid nodules

Thyroid nodules are common entities, clinically important primarily because of their malignant potential. Serum thyrotropin and thyroid ultrasonography are pivotal in evaluating thyroid nodules. Fine-needle aspiration biopsy is the most accurate tool for diagnosing malignancy and selecting candidates for surgery. An approach to the initial evaluation and management of single nodules, functioning nodules, multinodular glands, incidental nodules, and cysts is discussed, as are therapeutic interventions for benign nodules. Thyroid cancer discovered during pregnancy is also discussed.

Non-surgical approach to the benign nodular goiter: new opportunities by recombinant human TSH-stimulated 131I-therapy

The optimal treatment strategy in a goiter patient depends--among other factors--on goiter size, the degree of cosmetic or compressive symptoms, the age of the patient, the impact on the upper airways, the wish to maintain normal thyroid function, the ability of the thyroid gland to take up (131)I, and the possibility of thyroid malignancy. When treatment is warranted in a patient with benign goiter, the choice usually stands between surgery and (131)I-therapy. Focal destructive treatment, by ethanol sclerotherapy or interstitial laser photocoagulation, may be considered in patients with a solitary benign nodule. If thyroid hyperfunction due to nodular autonomy is the dominant problem, life-long anti-thyroid drug treatment may be relevant in elderly individuals. With the advent of recombinant human TSH (rhTSH) stimulation the goiter reduction following (131)I-therapy is significantly enhanced and this treatment is of particular benefit, as compared with conventional (131)I-therapy, in patients with a low baseline thyroid (131)I uptake and a large goiter. If the rhTSH dose does not exceed 0.1 mg the risk of temporary hyperthyroidism and acute thyroid swelling is low. Since patient satisfaction seemingly is not improved by the greater goiter reduction obtained by rhTSH-stimulated (131)I-therapy, and permanent hypothyroidism is more frequent, it may be more relevant to reduce the administered radioactivity equivalent to the rhTSH-induced increase in the thyroid (131)I uptake. Future large-scale well-controlled studies should explore this strategy, with focus on cost-benefit and quality of life. A major hindrance of widespread and routine use of rhTSH-stimulated (131)I-therapy is its present status as an off-label treatment.

Predictors of malignancy in patients with cytologically suspicious thyroid nodules

BACKGROUND

Fine needle aspiration (FNA), although very reliable for cytologically benign and malignant thyroid nodules, has much lower predictive value in the case of suspicious or indeterminate nodules. We aimed to identify clinical predictors of malignancy in the subset of patients with suspicious FNA cytology.

METHODS

We reviewed the electronic medical records of 462 patients who had FNA of thyroid nodules at our institution with a suspicious cytological diagnosis, and underwent surgery at Mayo Clinic between January 2004 and September 2008. Demographic data including age, gender, history of exposure to radiation and use of thyroid hormone was collected. The presence of single versus multiple nodules by ultrasonography, nodule size, and serum thyroid-stimulating harmone (TSH) level before thyroid surgery were recorded. Analysis of the latter was limited to patients not taking thyroid hormone or antithyroid drugs at the time of FNA.

RESULTS

Of the 462 patients, 327 had lesions suspicious for follicular neoplasm (S-FN) or Hürthle cell neoplasm (S-HCN), 125 had cytology suspicious for papillary carcinoma (S-PC) and 10 had a variety of other suspicious lesions (medullary cancer, lymphoma and atypical). Malignancy rate for suspicious neoplastic lesions (FN+HCN) was ∼15%, whereas malignancy rate for lesions S-PC was 77%. Neither age, serum TSH level, or history of radiation exposure were associated with increased malignancy risk. The presence of multiple nodules (41.1% vs. 26.4%, p=0.0014) or smaller nodule size (2.6±1.8 cm vs. 2.9±1.6 cm, p=0.008) was associated with higher malignancy risk. In patients with cytology suspicious for neoplasm (FN, HCN) malignancy risk was higher in those receiving thyroid hormone therapy than in nonthyroid hormone users (37.7% vs. 16.5%, p=0.0004; odds ratio: 3.1), although serum TSH values did not differ significantly between thyroid hormone users and nonusers.

CONCLUSION

In patients with cytologically suspicious thyroid nodules, the presence of multiple nodules or smaller nodule size was associated with increased risk of malignancy. In addition, our study demonstrates for the first time, an increased risk of malignancy in patients with nodules suspicious for neoplasm who are taking thyroid hormone therapy. The reason for this association is unknown.

The patient with a thyroid nodule

Nodular thyroid disease is common in the United States and throughout the world. Although most thyroid nodules are benign in nature, certain clinical, radiographic, and cytologic features are associated with an increased risk of malignancy. A clear understanding of these risk factors assists in the decision-making process when evaluating a patient with a thyroid nodule. It is this process that ultimately determines whether or not a patient is referred for surgery. This article provides a framework for clinicians to risk-stratify and appropriately manage patients with thyroid nodules.

Real-time ultrasound elastography--a noninvasive diagnostic procedure for evaluating dominant thyroid nodules

PURPOSE

Ultrasound elastography (USE) is a newly developed technique for the evaluation of tissue stiffness. It is known that malignancies often show a low-strain value. So far, only limited data for thyroid nodules is available.

METHODS

This study included 309 prospective evaluated patients with dominant, nontoxic thyroid nodules. All patients were referred to surgery. USE was performed preoperatively. Three measuring groups were formed: hard (< 0.15), intermediate (0.16-0.3), and soft (> 0.31). The measurements were correlated to the final histological findings.

RESULTS

The strain rated from 0.01 to 0.84 (mean 0.26 ± 0.13). A total of 50 thyroid malignancies (35 papillara carcinoma, 9 medullary carcinoma, and 6 follicular carcinoma) were observed. Patients (81) were within the hard group, 35 of them (43.2%) had thyroid cancer (TC) in final histology. Out of 132 patients in the intermediate group, 15 patients had TC (11.4%). All 96 patients from the soft group showed benign histological results (NPV 100%). Seventy percent of patients with TC were within the hard group (PPV 42%). These results were highly significant (p < 0.001). Coarse calcifications and cystic nodules were not connected with reliable measurements and therefore are not suitable for USE.

CONCLUSION

USE is a useful adjunctive tool in the workup of thyroid nodules. A low strain value needs surgical intervention, whereas a high strain value predicts a benign histology. It might substitute fine-needle aspiration cytology in the future.

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.

Levothyroxine therapy in preventing nodular recurrence after hemithyroidectomy: a retrospective study

AIM

To determine the effect of levothyroxine (L-T4) therapy on the recurrence rate of nodular disease in patients previously treated with lobectomy for benign nodular goiter.

METHODS

Two hundred and thirty-tree patients (38 males, 195 females; age 49.9+/-13.1 yr) with no post-surgical evidence of nodular disease in the remnant, were followed- up yearly with serum TSH and ultrasound (US). Nodular recurrence was defined as a lesion of at least 5 mm at US. Patients were divided in 2 groups based on whether or not they had been treated with L-T4 after surgery: Group 1 (45 patients) who did not receive any L-T4, and Group 2 (188 patients) treated with L-T4. Group 2 was further subdivided in Group 2a (123 patients) receiving L-T4 substitutive therapy (TSH>or=0.5 and <or=3 mUI/l) and Group 2b (65 patients) receiving L-T4 at TSH-suppressive dose (TSH<0.5 mUI/l).

RESULTS

Mean observation period was 5.8+/-4.7 yr. Overall, 71 out of 233 (30.5%) patients experienced recurrence of thyroid nodular disease: 29 patients (64.4%) in Group 1, 24 (19.5%) patients in Group 2a, and 18 (27.7%) patients in Group 2b. The recurrence rate was significantly lower (p<0.001) in Group 2 compared with Group 1, but no significant difference was observed between Groups 2a and 2b.

CONCLUSION

In patients who have undergone hemithyroidectomy for benign monolobar nodular disease, L-T4 therapy may prevent recurrence of nodular disease. TSH suppression may not be required for prevention of recurrence in the remnant thyroid tissue.

Evidence-based assessment of the role of ultrasonography in the management of benign thyroid nodules

BACKGROUND

Although ultrasonographic (US) evaluation is currently recommended for the workup of all palpable thyroid nodules, little guidance exists regarding the manner in which US data are to be used. Herein, we examine the available evidence and recommend how US can be used most effectively to predict malignancy. We discuss the role of US-guided fine needle aspiration (FNA) and other special topics regarding US evaluation and management of benign nodules.

METHODS

We also present a systematic review of the literature using evidence-based criteria.

RESULTS

US features alone cannot predict malignancy or benignity, but techniques that combine US features and FNA cytology are most effective and most accurate for predicting malignancy (Level III and IV evidence). US features suggesting malignancy include a blurred or ill-defined margin, irregular shape, solid echo structure, hypoechogenicity, absent halo, fine calcifications, and intranodular vascular pattern. Most patients with malignancies have more than two US features characteristic of malignancy. US-guided FNA has nonsignificantly higher sensitivity, specificity, and accuracy than the palpation-guided technique (Level III and IV evidence). US guidance is particularly beneficial in patients with nonpalpable, multiple, or heterogeneous nodules for preferentially aspirating a specific segment of the nodule (large or partially cystic nodule) or when nodule palpation is difficult (patients with diffuse glandular disease or obesity).

CONCLUSIONS

US is an essential component of thyroid nodule evaluation and management. Techniques that combine US features and FNA cytology for thyroid nodule workup are more accurate than either technique alone. US-guided FNA can decrease the rate of nondiagnostic aspirates.

The role of imaging in Graves’ disease: A cost-effectiveness analysis

According to many guidelines, scintigraphy remains the first suggested diagnostic procedure in hyperthyroid patients in spite of the widespread availability of ultrasounds. The aim of this study was to evaluate the cost-effectiveness of sonography versus scintigraphy in the management of Graves's disease, and to assess ultrasound features suggesting cancer in detecting thyroid nodules. Among 1470 hyperthyroid patients evaluated in our department from 2002 to 2005, 426 (29%) had Graves' disease: echographic and scintigraphic features were not suggestive of GD in 20/426 (4.8%) and 11/426 (2.6%) patients, respectively (p=0.763), even if one of the two procedures was almost always diagnostic. Ultrasound identified 68/426 (16%) patients with a concomitant solid lesion, while scintigraphy detected only 9/426 (2.1%) "cold" nodules (p<0.001). Thyroid cancer was diagnosed in 30/68 (47.7%) patients. Malignancy presented at ultrasound investigation blurred margins (26.7% versus 15.8%), microcalcifications (33.3% versus 28.9%) and an anteroposterior and transverse diameter ratio>or=1 (73.3% versus 71.1%); more frequently than benign nodules, but this was not statistically significant. The total cost to obtain a diagnosis by ultrasound was euro14645.34 (euro13312.5 for echography+euro1332.84 for scintigraphy in the 29 patients "negative" at echographic evaluation for GD) versus euro19922.71 by scintigraphy (euro19578.96 for scan+euro343.75 for ultrasounds in the 11 patients "negative" at scintigraphy). Our data show no difference in terms of diagnosis between sonography and scintigraphy. Indeed, scintigraphy was less sensitive in detecting nodules (often of malignant nature) than ultrasound, and, moreover, with a consequent increase of the direct cost of nodule management when scintigraphy is the first line procedure. In conclusion, according to our results, we suggest that ultrasounds with color-Doppler evaluation should be performed as first step in all hyperthyroid patients, and that scintigraphic examination should be limited only to the uncommon cases, where physician's observation, laboratory assays and/or ultrasounds are not diagnostic.

[Thyroid incidentaloma. Overdiagnosis and overtreatment of healthy persons with thyroid illness?]

Thyroid incidentalomas have been found in about 20% of cases screened by neck ultrasound, and asymptomatic thyroid cancer is detected in about 10% of autopsies. The incidence of clinically treated thyroid cancer in Germany is increasing without an increase in cancer-specific mortality. Presently the incidence is about 4500 cases per year (7.3/100,000, 3000 females). For early detection and treatment of clinical thyroid cancer ultrasonography-guided fine needle aspiration cytology of suspicious nodules therefore is crucial. Thyroid lobectomy is the treatment of choice for suspicious nodules to lower the risk of morbidity in case of reoperation due to a postoperative diagnosis of cancer. However, subtotal lobectomy may also be justified, especially with nodules in anterior position, because the risk of malignancy is only 3-5%. Frozen selection and/or early final histopathology should be available to avoid two-stage thyroid cancer operations.

Role of apparent diffusion coefficient values in differentiation between malignant and benign solitary thyroid nodules

BACKGROUND AND PURPOSE

Accurate imaging characterization of a solitary thyroid nodule has been clearly problematic. The purpose of this study was to evaluate the role of the apparent diffusion coefficient (ADC) values in the differentiation between malignant and benign solitary thyroid nodules.

MATERIALS AND METHODS

A prospective study was conducted in 67 consecutive patients with solitary thyroid nodules who underwent diffusion MR imaging of the thyroid gland. Diffusion-weighted MR images were acquired with b factors of 0, 250, and 500 s/mm(2) by using single-shot echo-planar imaging. ADC maps were reconstructed. The ADC values of the solitary thyroid nodules were calculated and correlated with the results of histopathologic examination. Statistical analysis was performed.

RESULTS

The mean ADC value of malignant solitary thyroid nodules was 0.73 +/- 0.19 x 10(-3) mm(2)/s and of benign nodules was 1.8 +/- 0.27 x 10(-3) mm(2)/s. The mean ADC values of malignant nodules were significantly lower than those of benign ones (P = .0001). There were no significant differences between the mean ADC values of various malignant thyroid nodules, but there were significant differences between the subtypes of benign thyroid nodules (P = .0001). An ADC value of 0.98 x 10(-3) mm(2)/s was proved as a cutoff value differentiating between benign and malignant nodules, with 97.5%, 91.7%, and 98.9% sensitivity, specificity, and accuracy, respectively.

CONCLUSION

The ADC value is a new promising noninvasive imaging approach used for differentiating malignant from benign solitary thyroid nodules.

Feasibility, Accuracy, and Clinical Relevance of a Rapid Thyroid Evaluation During Carotid Duplex Ultrasonography in Hypertensive Patients

Carotid ultrasonography can detect thyroid nodules without increasing examination duration. The authors analyzed whether management is influenced by reporting such findings during routine carotid ultrasonography in hypertensive patients vs waiting for 6 months to repeat them. This is a population-based study of 1216 hypertensive patients. During carotid ultrasonography, nodule cystic/solid characteristics and size of thyroid changes were recorded. Patients with nodules were divided into those with nodules reported at the moment of diagnosis (group A) and those reported 6 months after diagnosis (group B). The authors monitored patients who underwent thyroid treatment 12 months after carotid ultrasonography. A total of 255 participants had thyroid nodules detected on screening and 99 patients started therapy after discovery. Six months later, as expected, there were more patients undergoing thyroid treatment in the group with nodules reported at time of diagnosis. This difference between groups was not significant, however, 6 months after reporting the nodules, in group B, because the number of patients on therapy significantly increased. Thyroid nodules cannot be ignored during carotid ultrasonography, and reporting their presence is valuable to general practitioners. Thyroid screening during carotid ultrasonography is cost-effective, rapid, sensitive, and specific and may affect the patient's diagnostic and therapeutic management.

[The role of intraoperative ultrasound in surgery for benign nodular goiter]

BACKGROUND

In treating benign nodular goiter, selective surgery taking into account morphology and function is better than standard subtotal resection for reducing the frequency of nodules in the thyroid remnant. Intraoperative ultrasound (IOPUS) may additionally influence operative radicality and also the incidence of remaining nodules.

METHODS

One hundred consecutive patients with benign nodular goiter were operated on with IOPUS; the specimens were compared with results of preoperative ultrasound and intraoperative palpation. Of these patients, 80 were reinvestigated after 3+/-1.6 years. A series of 80 patients with the same operative strategy but without IOPUS was used as control group, having been reinvestigated sonographically 1 year postoperatively, and was compared to the IOPUS group with respect to operative procedures, size of remnants, and sonography of lesions in thyroid remnants.

RESULTS

In 35% of the thyroid lobes, preoperatively undetected nodules could be identified additionally by IOPUS, which also provided information on extent and structure in a further 20%. It resulted in the indication for more radical surgery in 24% and greater tissue preservation in 10%. Compared to surgery without IOPUS, IOPUS-guided surgery was more radical (total lobectomy in 40% vs 24%, nonresected lobes in 16% vs 26%, P<0.05) and showed a lower incidence of nodules in remnants at follow-up (2.5% vs 12.5%, P<0.05).

CONCLUSIONS

With IOPUS, more nodules are detectable, size and structure of the remnants are optimized, and the number of nodular lesions in thyroid remnants is lower. Thus, an even lower risk of recurrence can be expected for long-term follow-up. All in all, the routine use of IOPUS can be advocated, with maintenance of the selective operative strategy.

The thyroid incidentaloma: an increasingly frequent consequence of radiologic imaging

Incidentally discovered thyroid lesions have become increasingly common with the development and more frequent utilization of highly sensitive imaging modalities throughout the clinical practice of medicine. Determining the most appropriate management of these "incidentalomas" has presented a significant challenge to both endocrinologists and endocrine surgeons. Algorithms with which to accurately identify those malignant lesions hidden amongst the overwhelming majority of those which are benign have not yet been established. This article will review the existing literature concerning the subject of thyroid incidentalomas and recommend a methodical approach to evaluating these patients such that the greatest number of malignancies may be detected while subjecting the fewest patients with benign lesions to unnecessary testing. Additionally, the role of the radiologist as an integral part of the multidisciplinary team of surgeons, endocrinologists, and cytologists working together to identify those patients with the highest risk of malignancy will be explored.

Ultrasound in head and neck surgery: thyroid, parathyroid, and cervical lymph nodes

Ultrasound (US) of the neck is extremely sensitive in detecting thyroid, parathyroid, and cervical lymph node pathology, and is regarded as the most complete and cost-effective imaging method for evaluating the thyroid and parathyroid glands, as well as for the diagnostic evaluation of the cervical lymph node basin. US is widely used in screening high-risk individuals, evaluation of palpable and nonpalpable thyroid nodules, needle guidance for biopsy of nonpalpable and suspicious nodules, and preoperative evaluation of the extent of thyroid neoplasms, as well as in the detection of residual, recurrent, or metastatic thyroid tumors, and in observing nonsurgical cases. It has thus become an important adjunct to the practice of head and neck surgery.

Management of thyroid incidentalomas

The discovery of a thyroid incidentaloma warrants a systematic approach for those nodules most likely to be cancerous. An optimal management strategy for thyroid incidentalomas should be guided by four questions: (1) Does the incidentally detected thyroid nodule put the patient at risk for an adverse outcome; (2) Can those individuals with malignant thyroid nodules be identified; (3) Is the treatment of thyroid malignancy more effective in presymptomatic patients; and (4) Do the beneficial effects of presymptomatic detection and treatment in these patients justify the costs incurred Physicians caring for patients with thyroid disease should participate in data acquisition in national databases and properly randomized studies, to address the optimal management strategy in the treatment of incidentally-detected thyroid nodules.

Prevalence, clinical and ultrasonographic characteristics of thyroid incidentalomas

High-resolution ultrasonography (US) has made possible the detection of asymptomatic small thyroid nodules. Thyroid incidentalomas have created a clinical dilemma as to how to properly manage such incidental findings. We investigated the prevalence, the clinical and US characteristics, and optimal diagnostic approach to incidentally detected benign and malignant thyroid nodules < 1.5 cm. Retrospective review was done on 1475 patients who had visited Samsung Medical Center, Soul Korea from January 1999 to December 2000. The prevalence of thyroid incidentalomas was 13.4%. The malignancy rate within thyroid incidentalomas was 28.8%. There were no significant differences in age, nodule size and number, thyroid function test, and Tc99m thyroid scan between benign and malignant incidentalomas. US characteristics of solid echostructure, irregular margin, and calcification showed meaningful diagnostic value in detecting malignancy in thyroid incidentalomas (p < 0.05). Most malignant incidentalomas were low stage. In conclusion, occult thyroid cancers are a fairly common finding. There were no significant differences in clinical and laboratory parameters between benign and malignant thyroid nodules <1.5 cm; however, US findings can be used in the decision of optimal management strategies.

Thyroid nodules: diagnosis and therapy

Less than 1% of all cancers are present in the thyroid, yet thyroid nodules are found in 4 to 10% of the adult population. Because thyroid nodules are relatively common, the diagnostic dilemma is to distinguish between a more common benign nodule, which usually does not require specific treatment, and a malignant nodule, which requires thyroidectomy and further treatment. Thyroid nodules usually are an incidental finding on a routine examination by a primary care physician. When patients seek treatment for symptomatic nodules, a more serious problem may be indicated, and thyroid cancer is suggested. However, additional studies have demonstrated the use of genetic markers and immunohistochemistry in the diagnosis of thyroid nodules, which may lead to a more rational approach to the treatment. This article reviews literature published in the last 12 months pertaining to the pathogenesis, diagnosis, and treatment of thyroid nodules.

Sonography and scintigraphy are necessary in diagnostics of cystic thyroid lesions

Thyroid sonography in an otherwise asymptomatic 50-year-old woman revealed a mainly cystic lesion within the right thyroid lobe. Thyroid (99)Tc scan showed an enhanced uptake over the right thyroid lobe with suppressed activity over the remaining thyroid tissue. Following aspiration of 6 ml of cyst fluid, a solid lesion became apparent in the location of the original cyst corresponding to the scintigraphically detected autonomous adenoma. This case report emphasizes that ultrasonography and scintigraphy are complementary methods and should be used as such in the primary evaluation of thyroid nodules.

Thyroid cancer following exposure to radioactive iodine

The thyroid gland is one of the most sensitive organs for radiation-induced oncogenesis and the magnitude of the risk from external radiation is well understood. This is not the case for internal radiation derived from the radioiodines, a matter of practical importance because of medical use and potential accidental exposure. This article reviews current knowledge derived from the follow-up of patients receiving diagnostic or therapeutic 131I and populations exposed to radioactive fallout. The latter includes the nuclear power station accident at Chernobyl and the results of atomic bomb development and testing at Hanford, the Nevada Test Site and the Marshall Islands. The most cogent information comes from Chernobyl where an epidemic of childhood thyroid cancer has followed exposure to radioiodine that was mainly 131I. Although much has been learned from this experience about the nature of radioiodine induced thyroid cancer in young children, the reconstruction of thyroid radiation doses is too preliminary to provide accurate knowledge of the risk in comparison to that from external radiation. In the Marshall Islands, much of the exposure was from short-lived radioiodines as well as external radiation, obviating the possibility to determine the risk from 131I. Exposure to 131I in the continental United States from atomic bomb testing is expected to have caused some thyroid cancers, but only in the immediate vicinity of the Nevada Test Site has any evidence of radiation-induced thyroid neoplasms been adduced. This evidence is minimally significant statistically, and not significant for thyroid cancer per se. Medical use of radioiodine has not been observed to cause thyroid cancer but very few of the patients studied were young children, the group most sensitive to thyroid radiation. Despite these limitations, this information is sufficient to make some suggestions concerning protective measures in the case of nuclear accidents and the follow up of individuals who have been exposed.

The use of fine-needle aspiration biopsy under ultrasound guidance to assess the risk of malignancy in patients with a multinodular goiter

PURPOSE

Fine-needle aspiration biopsy (FNAB) is a commonly performed procedure used in the evaluation of solitary thyroid nodules, in which the risk of malignancy is approximately 5% in most patients. Recently, the use of ultrasound (US) guidance in FNAB has been shown to enhance the diagnostic efficacy of this procedure. However, the risk of malignancy in thyroid nodules occurring within a multinodular goiter (MNG) has not been completely clarified, nor has the optimal means of investigating such nodules using FNAB.

SUBJECTS AND METHODS

We performed a retrospective study of all patients seen over a 4-year period with a MNG that had one or more nodules who underwent FNAB under US guidance. The results from the history and physical examination, thyroid function and antibody tests, radionuclide studies, thyroid sonogram, cytology of aspirated nodules, and surgical pathology were recorded and analyzed.

RESULTS

A total of 93 nodules were aspirated in 61 patients with MNG. Adequate material was obtained in 96% of aspirates on the first attempt. Sixty-seven aspirates in 44 patients yielded benign cytology and 22 aspirates in 15 patients yielded suspicious cytology. All patients with suspicious cytology underwent thyroid surgery. Thyroid cancer was found in 5 of these nodules, including 4 cases of papillary cancer and 1 case of Hürthle cell cancer, and 1 additional patient had occult papillary cancer discovered. The overall malignancy rate in thyroid nodules among the patients with MNG was approximately 5%.

CONCLUSIONS

FNAB under US guidance is a useful diagnostic modality in the evaluation of thyroid nodules in selected patients with MNG. Because the risk of thyroid malignancy in these nodules is comparable to that which exists in solitary thyroid nodules, the possibility of thyroid malignancy should be considered in all patients with MNG.

Use of thyroid ultrasound volume in calculating radioactive iodine dose in hyperthyroidism

One hundred twenty-one patients treated with 131I had a thyroid ultrasound to measure thyroid volume precisely. This volume measurement was used to determine the radioactive iodine dose. The average size (+/-SEM) of the thyroid glands measured in this manner was 39.7 cm3 +/- 1.9 cc. A significant correlation was found in the estimated size of the gland by the endocrinologists and the ultrasound volume. Of the 121 patients, 89 patients had the same 131I microcurie per gram of tissue factor to determine the radioactive iodine dose. This group of patients was further evaluated in this study. The average 131I dose (+/-SEM) given was 13.2 mCi +/- 0.5 mCi. The average time until hypothyroidism was achieved 2.85 +/- 0.14 months. Ultrasound provides a safe and precise way to determine actual thyroid size when calculating 131I doses.

Thyroid disease in women

Thyroid diseases occur more commonly in women than men, in part because of the autoimmune nature of many thyroid disorders. Hypothyroidism, and thyroid nodules occur frequently in both pre- and postmenopausal women. Pregnancy is also associated with changes in thyroid function. The goal of this article is to review the current information on the pathophysiology and treatment of thyroid disorders which are common in women.