The thyroid and parathyroid glands. CT and MR imaging and correlation with pathology and clinical findings

The Relationship between Renin-Angiotensin-Aldosterone System (RAAS) Activity, Osteoporosis and Estrogen Deficiency in Type 2 Diabetes

Type 2 diabetes (T2D) is associated with a plethora of comorbidities, including osteoporosis, which occurs due to an imbalance between bone resorption and formation. Numerous mechanisms have been explored to understand this association, including the renin-angiotensin-aldosterone system (RAAS). An upregulated RAAS has been positively correlated with T2D and estrogen deficiency in comorbidities such as osteoporosis in humans and experimental studies. Therefore, research has focused on these associations in order to find ways to improve glucose handling, osteoporosis and the downstream effects of estrogen deficiency. Upregulation of RAAS may alter the bone microenvironment by altering the bone marrow inflammatory status by shifting the osteoprotegerin (OPG)/nuclear factor kappa-Β ligand (RANKL) ratio. The angiotensin-converting-enzyme/angiotensin II/Angiotensin II type 1 receptor (ACE/Ang II/AT1R) has been evidenced to promote osteoclastogenesis and decrease osteoblast formation and differentiation. ACE/Ang II/AT1R inhibits the wingless-related integration site (Wnt)/β-catenin pathway, which is integral in bone formation. While a lot of literature exists on the effects of RAAS and osteoporosis on T2D, the work is yet to be consolidated. Therefore, this review looks at RAAS activity in relation to osteoporosis and T2D. This review also highlights the relationship between RAAS activity, osteoporosis and estrogen deficiency in T2D.

The possibilities of ultrasound imaging in the diagnosis of follicular neoplasia of the thyroid gland

Thyroid cancer is the most common cancer of the endocrine system. The diagnosis of thyroid cancer has taken a step forward due to the introduction of fine-needle biopsy of the thyroid gland with subsequent evaluation of cytological material using the Bethesda system. One category of this classification traditionally remains a gray area of diagnosis. The detection of a follicular tumor in the cytological material (category IV according to Bethesda) does not allow one to reliably classify the neoplasia as benign or malignant and requires surgical intervention. The traditional informative and widely used method for diagnosing thyroid tumors is ultrasound. However, the sensitivity and specificity of the method varies over a wide range. This review analyzes the literature on the possibilities of ultrasound diagnostics in assessing the malignant potential of follicular tumors of the thyroid gland.

The Role of Imaging in the Detection of Non-COVID-19 Pathologies during the Massive Screening of the First Pandemic Wave

During the COVID-19 pandemic induced by the SARS-CoV-2, numerous chest scans were carried out in order to establish the diagnosis, quantify the extension of lesions but also identify the occurrence of potential pulmonary embolisms. In this perspective, the performed chest scans provided a varied database for a retrospective analysis of non-COVID-19 chest pathologies discovered de novo. The fortuitous discovery of de novo non-COVID-19 lesions was generally not detected by the automated systems for COVID-19 pneumonia developed in parallel during the pandemic and was thus identified on chest CT by the radiologist. The objective is to use the study of the occurrence of non-COVID-19-related chest abnormalities (known and unknown) in a large cohort of patients having suffered from confirmed COVID-19 infection and statistically correlate the clinical data and the occurrence of these abnormalities in order to assess the potential of increased early detection of lesions/alterations. This study was performed on a group of 362 COVID-19-positive patients who were prescribed a CT scan in order to diagnose and predict COVID-19-associated lung disease. Statistical analysis using mean, standard deviation (SD) or median and interquartile range (IQR), logistic regression models and linear regression models were used for data analysis. Results were considered significant at the 5% critical level (p < 0.05). These de novo non-COVID-19 thoracic lesions detected on chest CT showed a significant prevalence in cardiovascular pathologies, with calcifying atheromatous anomalies approaching nearly 35.4% in patients over 65 years of age. The detection of non-COVID-19 pathologies was mostly already known, except for suspicious nodule, thyroid goiter and the ascending thoracic aortic aneurysm. The presence of vertebral compression or signs of pulmonary fibrosis has shown a significant impact on inpatient length of stay. The characteristics of the patients in this sample, both from a demographic and a tomodensitometric point of view on non-COVID-19 pathologies, influenced the length of hospital stay as well as the risk of intra-hospital death. This retrospective study showed that the potential importance of the detection of these non-COVID-19 lesions by the radiologist was essential in the management and the intra-hospital course of the patients.

An unusual case of neck hematoma and hypercalcemia

One of the most frequent cause of hypercalcemia is primary hyperparathyroidism, which can lead to systemic involvement and life-threatening conditions. We described a rare case of a parathyroid adenoma rupture with consequent bleeding and respiratory airway compression. An 84-year-old man presented to the emergency department complaining neck swelling and related dysphagia. A computer tomography of the neck revealed an extensive left lateral hematoma, and a neck ultrasonography evidenced a hemorrhagic parathyroid adenoma, later confirmed by a 99 mTc-MIBI scintigraphy. To date only 40 cases of ruptured parathyroid adenomas have been described in literature, however due to the possibility of massive bleeding and compression of the airways this diagnosis should always be ruled out. The rupture of a parathyroid adenoma is a rare, but possibly life-threatening event due to airways compression and hemodynamic instability. Testing for hypercalcemia and hyperparathyroidism is mandatory to obtain a correct diagnosis.

Incidental Thyroid Nodules on Imaging: Relevance and Management

Incidental thyroid nodules (ITNs) are commonly detected on imaging examinations performed for other reasons, particularly computed tomography (CT) (and now PET-CT and even PET-MR imaging), MR imaging, and sonography, primarily a consequence of the increasing sensitivity of these diagnostic modalities. Appropriate management of ITNs is crucial to avoid the cost and medical consequences of unnecessary workups.

The Value of Sonography in Distinguishing Follicular Thyroid Carcinoma from Adenoma

Purpose

Differentiation between follicular thyroid carcinomas (FTCs) and follicular thyroid adenomas (FTAs) is difficult and the sonographic features of FTC are not yet fully established. The purpose of this study is to explore the sonographic features of FTC and the value of sonography in differentiating FTCs from FTAs.

Patients and Methods

A total of 28 pathologically proven FTCs and 53 FTAs in 78 patients who were performed thyroid surgery were included in this retrospective study. The sonographic features of each tumor including an interrupted halo, satellite nodule(s) with or without halo ring, local irregularity of margin and cluster of grapes sign were evaluated. A mode image of FTC halo was built up in our study. The frequencies of the sonographic features were compared by chi-square test or Fisher exact test between FTCs and FTAs. The relative risk of malignancy was assessed by logistic regression analysis.

Results

Logistic regression analysis showed that a thick, irregular and/or interrupted halo with or without satellite nodule(s), hypoechoic or marked hypoechoic echogenicity, a predominantly solid pattern, cluster of grapes sign, micro-or macro-calcifications, rim calcifications correlated with significant increases in relative risk for FTCs (odds ratio 11.48 (1.37-96.56), 6.74 (1.05-43.30), 17.51 (1.78-172.53), 9.55 (1.44-63.46), 9.36 (1.25-70.15) and 17.45 (1.04-292.65), respectively, p<0.05). Two new sonographic features, an interrupted halo and satellite nodule(s) with or without halo ring, can only be found in FTCs.

Conclusion

An interrupted halo and satellite nodule(s) with or without halo ring are specific sonographic features for FTCs. Sonography could play a role in differentiating follicular thyroid carcinoma from adenoma.

Feasibility study of using virtual non-contrast images derived from dual-energy CT to replace true non-contrast images in patients diagnosed with papillary thyroid carcinoma

OBJECTIVE

To assess the feasibility of using virtual non-contrast (VNC) images derived from dual-energy computed tomography (DECT) to replace true non-contrast (TNC) images of papillary thyroid carcinoma (PTC) patients.

METHODS

Images of 96 PTC patients were retrospectively analyzed. TNC images were acquired under the single-energy mode of DECT after the plain scanning. The arterial and venous phase VNC (VNC-a and VNC-v) images were generated by the post-processing algorithm from the arterial phase and venous phase of contrast-enhanced CT images, respectively. Mean attenuation values, image noise, number and length of calcification were measured. Radiation dose was also calculated. Last, subjective score of image quality was evaluated by a 5-point scale.

RESULTS

Signal-to-noise ratio (SNR) of each tissue in TNC images is significantly higher than that of VNC images (p<0.050). Contrast-to-noise ratio (CNR) of fat, muscle, thyroid nodules and internal carotid artery in TNC images is significantly higher than that of VNC images, while CNR in TNC images is lower for cervical vertebra (p<0.001). Calcification is detected on TNC images of 44 patients, while it is omitted on VNC images of 14 patients (31.8%). The subjective score of TNC images is higher than VNC images (p<0.001). The effective dose reduction is 47.6% by avoiding plain scanning.

CONCLUSIONS

Considering the different attenuation value, SNR, CNR and especially reduced detection rate of calcification, we deem that VNC images cannot be directly used to replace TNC images in PTC patients, despite the reduced radiation dose.

Can quantitative diffusion-weighted MR imaging differentiate between different subtypes of benign and malignant solitary thyroid nodules?

Background

Diffusion-weighted MR imaging (DWI) is sensitive to changes in the microstructural organization of tissue that may influence water diffusion. It has been utilized in various forms to evaluate head and neck tumors. The apparent diffusion coefficient (ADC) value is a quantitative parameter for distinguishing malignant from benign thyroid nodule. Determination of different pathologic types of the thyroid nodules is crucial for appropriate therapeutic approach. Our point was to assess the utility of apparent diffusion coefficient values in discriminating different subtypes of benign and malignant solitary thyroid nodules using diffusion MRI with pathological correlation.

Results

This prospective study included 73 patients who had thyroid nodules. The size of the investigated lesions ranged from 0.6 to 3 cm. Most nodules were benign (79.45%), and most of these benign nodules were adenomatous nodules. There was a significant difference in ADC values of benign and malignant thyroid nodules (P 0.0001), with the mean ADC value for the benign group (1.7 ± 0.12 × 10-3) higher than that for malignant nodule (0.71 ± 0.15 × 10). The sensitivity, specificity, and accuracy of ADC in differentiating between benign and malignant thyroid nodules were 97.5, 94.4, and 99.2%, respectively. We noticed a significant overlap in the ADC value of pathological subtypes and upon reviewing the pathological results, we found insignificant differences in the ADC values of the various subtypes of malignant and benign nodules, with P value ranging from 0.054 to 0.062 between different pathological subtypes. A significant difference was only noted between non-complicated cysts and solid nodules P 0.0001. In our series, an ADC value of 0.92 × 10-3 mm2/s or less could be used as an indicator of malignancy, with a sensitivity of 97.5%, a specificity of 94.4%, and an accuracy of 99.2%.

Conclusion

Diffusion MRI including ADC values are helpful in differentiation between benign and malignant thyroid nodules but not helpful in differentiating between different subtypes of benign and malignant nodules.

AGGRESSIVE PAPILLARY CARCINOMA OF THE LATERAL ABERRANT THYROIDE: A CASE REPORT AND REVIEW OF THE LITERATTUREggressive papillary carcinoma of the lateral aberrant thyroide: A case report and review of the literatture

INTRODUCTION

Ectopic thyroid tissue can be found in many sites. Ectopic thyroid tissue may also be involved in the same processes as normal thyroid gland. These processes include tumors, inflammation and hyperplasia. The appearance of such tissue in rare locations may lead to diagnostic and therapeutic dilemmas.

PRESENTATION OF CCASE

We report a rare case of primary papillary carcinoma in an ectopic thyroid in the jugulocarotid regionbased on the bifurcation of the carotid artery, in a 62-year-old woman with history of diabetes and high blood pressure, with a normal thyroid gland.

DISCUSSION

The origin of lateral ectopic thyroid tissue is not fully understood and controversial.The lateral localisation is a rare entity and debated extensively in the literature.

CONCLUSION

Though rare, the possibility of an ectopic thyroid carcinoma must always be considered by the surgeon in cases of a pathological mass in the neck.

The Diagnostic Value of Ultrasound in Medullary Thyroid Carcinoma: A Comparison With Computed Tomography

Purpose:

To explore the clinical value of ultrasound in the diagnosis of medullary thyroid carcinoma by comparing with enhanced computed tomography.

Methods:

This retrospective study was performed on 62 patients with pathologically confirmed medullary thyroid carcinoma. All patients underwent ultrasound and enhanced computed tomography examinations before surgery. The findings of the pathologic examination of resected specimens were considered as gold standard and were compared with the results of these 2 methods.

Results:

There were 73 medullary thyroid carcinoma lesions and 29 benign lesions in 62 patients. In all, 55 of 73 medullary thyroid carcinoma lesions and 27 of 29 benign lesions were correctly diagnosed by ultrasound; and 45 of 73 medullary thyroid carcinoma lesions and 24 of 29 benign lesions were correctly diagnosed by enhanced computed tomography. The accuracy of ultrasound and enhanced computed tomography was 80.4% and 67.6%, respectively. There was significant difference between 2 methods (P < .05).

Conclusions:

Ultrasound can be used to observe the location, number, size, shape, border, internal echo, calcification, and blood flow of the lesion. It is a convenient, inexpensive, and nonradiative method with higher accuracy than enhanced computed tomography.

Usefulness of intraoperative determination of central lymph node metastasis by palpation in papillary thyroid cancer

Background

This study evaluated the usefulness of judgment of central lymph node (LN) metastasis by surgeon’s palpation in papillary thyroid cancer.

Methods

This study included 127 patients who underwent thyroidectomy and central compartment node dissection between October 2014 and February 2015. The criterion for suspicious LNs was hardness.

Results

Of the 20.5% (28/127) of suspicious for metastatic LNs according to surgeon determination, 92.8% (26/28) were confirmed to be metastatic in the final pathological examinations. Metastatic LNs were found in 38 (38.3%) of 99 patients without suspicious LNs, 29 of whom (76.3%) had micrometastases. The sensitivity, specificity, and positive and negative predictive values for the determination of LN metastasis by a surgeon were 40.6%, 96.8%, 92.9%, and 61.6%, respectively.

Conclusion

Determination of central LN metastasis by a surgeon’s palpation may be useful to evaluate LNs owing to the high specificity and positive predictive values, especially in macrometastasis or high-risk LN disease.

Parathyroid Cancer: A Review

Parathyroid cancer is one of the rarest causes of primary hyperparathyroidism and tends to present with more severe symptoms than its more benign counterparts. This article details various aspects of the disease process, including epidemiology, clinical presentation, and a step-wise diagnostic process for parathyroid cancer. This includes laboratory assessments as well as a proposed staging system. The en bloc principle of surgical intervention is detailed, as well as the current role of adjuvant treatments. A general guide to surveillance and the natural history of the disease is also outlined.

Parathyroid Cancer: A Review

Parathyroid cancer is one of the rarest causes of primary hyperparathyroidism and tends to present with more severe symptoms than its more benign counterparts. This article details various aspects of the disease process, including epidemiology, clinical presentation, and a step-wise diagnostic process for parathyroid cancer. This includes laboratory assessments as well as a proposed staging system. The en bloc principle of surgical intervention is detailed, as well as the current role of adjuvant treatments. A general guide to surveillance and the natural history of the disease is also outlined.

Endobronchial ultrasound-guided transbronchial needle aspiration for thyroid cyst therapy: A case report

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is of limited usefulness for diagnosing thyroid disease, and few studies have reported its use in diagnosing and treating thyroid cysts. The present study investigated a unique case of diagnosis and treatment of a thyroid cyst by EBUS-TBNA. A 67-year-old male presented with back pain. Positron emission tomography/computed tomography scanning revealed low-density signals in the right lobe of the thyroid. Needle aspiration biopsies and drainage at this site was performed, and EBUS was used for guidance in diagnosing the thyroid cyst. A follow-up chest computed tomography scan indicated that the thyroid lesion had subsequently disappeared. The present study concludes that EBUS-TBNA provides an alternative approach for diagnosing and treating deep thyroid cysts located close to the airway. In all other cases, percutaneous needle aspiration or surgery should be the first choice.

Analysis of arterial dynamic micro-vascularization with contrast-enhanced ultrasound (CEUS) in thyroid lesions using external perfusion software: First results

AIM

To determine different perfusion characteristics of histo-pathologically proven adenomas and carcinomas of the thyroid gland with CEUS and perfusion software.

MATERIAL AND METHODS

Retrospective perfusion analysis of 25 patients with carcinomas and 41 cases of adenomas of the thyroid gland (30 males, 36 females; aged 18 - 85 years, mean 56 years). All cases were histologically analyzed. Perfusion analysis was independently performed using external perfusion software (VueBox®). TTP, mTT, Peak and Rise time were calculated.

RESULTS

Lesions' sizes ranged from 0.2 to 10.2 cm in carcinomas (mean 2.18 cm), and from 0.6 to 5.0 cm in adenomas (mean 2.25 cm). In 20 out of 25 carcinomas that were evaluated with CEUS, a complete wash-out in the late venous phase was found. Adenomas showed wash-out at the border.Perfusion analysis in VueBox® revealed some parameters which tend to show differences between adenomas and carcinomas, however did not reach the level of significance.Median Peak in carcinomas was highest at the margins (2945 rU), and lowest in the surroundings (1110 rU). Mean Transit Time (mTT) values showed no differences between center, margin and surrounding.In adenomas healthy tissue showed higher mTT values compared to the center (24.6 vs. 20.7 sec). Median Peak was highest in the surrounding tissue and lowest in the margins (1999 vs. 1129 rU). No statistical differences could be found in the comparisons.

CONCLUSION

CEUS with perfusion analysis offers new possibilities for the dynamic evaluation of micro-vascularization in thyroid adenomas and carcinomas. Using VueBox® the perfusion analysis of the arterial phase provides new parameters that help determine a lesion's malignancy or benignity. However a final assessment regarding malignancy and benignity of thyroid lesions using only CEUS and perfusion analysis of the arterial phase is not yet possible.

Clinicopathological characteristics of thyroid cancer misdiagnosed by fine needle aspiration

Fine-needle aspiration (FNA) is commonly used as a preoperative assessment to diagnose thyroid cancer. However, misdiagnosis of malignancy by FNA is not rare, even if image examination suggests the possibility of thyroid cancer. In the present study, the clinicopathological factors of patients whose preoperative FNA examination had not led to a diagnosis of thyroid cancer were examined. In total, 125 patients with thyroid cancer who underwent FNA and surgery (total thyroidectomy, subtotal thyroidectomy or hemithyroidectomy) at the Department of Surgery, Surgical Oncology and Science of the Sapporo Medical University Hospital between 2006 and 2013 were retrospectively analyzed. The patients were divided into two groups: Group A, malignancy determined by FNA, and group B, no malignancy. The groups were then compared by gender, age, tumor size, stage, tumor stage, lymph node metastasis, histology, surgical procedure methods, presence or absence of calcification and thyroglobulin levels. The mean age of the patients in group A (5 males and 59 females) was 53.0 years. The mean age in group B (11 males and 49 females) was 54.2 years. The mean tumor size in both groups was 1.6 cm. The mean thyroglobulin levels were 82.7 ng/ml in Group A and 525.5 ng/ml in group B. There were also significant differences between the groups for tumor stage (P=0.046), histological type (P=0.024) and thyroglobulin levels (P=0.035). The results of the present study suggested that it may be difficult to diagnose thyroid cancer by FNA in cases with non-papillary carcinoma and higher thyroglobulin levels.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ASSOCIAZIONE MEDICI ENDOCRINOLOGI MEDICAL GUIDELINES FOR CLINICAL PRACTICE FOR THE DIAGNOSIS AND MANAGEMENT OF THYROID NODULES--2016 UPDATE

Thyroid nodules are detected in up to 50 to 60% of healthy subjects. Most nodules do not cause clinically significant symptoms, and as a result, the main challenge in their management is to rule out malignancy, with ultrasonography (US) and fine-needle aspiration (FNA) biopsy serving as diagnostic cornerstones. The key issues discussed in these guidelines are as follows: (1) US-based categorization of the malignancy risk and indications for US-guided FNA (henceforth, FNA), (2) cytologic classification of FNA samples, (3) the roles of immunocytochemistry and molecular testing applied to thyroid FNA, (4) therapeutic options, and (5) follow-up strategy. Thyroid nodule management during pregnancy and in children are also addressed. On the basis of US features, thyroid nodules may be categorized into 3 groups: low-, intermediate-and high-malignancy risk. FNA should be considered for nodules ≤10 mm diameter only when suspicious US signs are present, while nodules ≤5 mm should be monitored rather than biopsied. A classification scheme of 5 categories (nondiagnostic, benign, indeterminate, suspicious for malignancy, or malignant) is recommended for the cytologic report. Indeterminate lesions are further subdivided into 2 subclasses to more accurately stratify the risk of malignancy. At present, no single cytochemical or genetic marker can definitely rule out malignancy in indeterminate nodules. Nevertheless, these tools should be considered together with clinical data, US signs, elastographic pattern, or results of other imaging techniques to improve the management of these lesions. Most thyroid nodules do not require any treatment, and levothyroxine (LT4) suppressive therapy is not recommended. Percutaneous ethanol injection (PEI) should be the first-line treatment option for relapsing, benign cystic lesions, while US-guided thermal ablation treatments may be considered for solid or mixed symptomatic benign thyroid nodules. Surgery remains the treatment of choice for malignant or suspicious nodules. The present document updates previous guidelines released in 2006 and 2010 by the American Association of Clinical Endocrinologists (AACE), American College of Endocrinology (ACE) and Associazione Medici Endocrinologi (AME).

The differential diagnosis of central compartment radioactive iodine uptake after thyroidectomy: anatomic and surgical considerations

OBJECTIVE

Foci of increased radioactive iodine (RAI) uptake in the thyroid bed following total thyroidectomy (TT) indicate residual thyroid tissue that may be benign or malignant. The use of postoperative RAI therapy in the form of remnant ablation, adjuvant therapy, or therapeutic intervention is often followed by a posttherapy scan. Our objective is to improve the clinician's understanding of the anatomic complexity of this region and to enhance the interpretation of postoperative scans.

METHODS

We conducted a comprehensive review of the literature evaluating RAI uptake in the central compartment following thyroid cancer treatment and literature related to anatomic nuances associated with this region. Thirty-eight articles were selected.

RESULTS

Through extensive surgical experience and a literature review, we identified the 5 most important anatomic considerations for clinicians to understand in the interpretation of foci of increased RAI uptake in the thyroid bed on a diagnostic scan: 1) residual benign thyroid tissue at the level of the posterior thyroid ligament, 2) residual benign thyroid tissue at the superior portion of the pyramidal lobe and/or superior poles of the lateral thyroid lobes, 3) residual benign thyroid tissue that was left attached to a parathyroid gland in order to preserve its vascularity, 4) ectopic benign thyroid tissue, and 5) malignant thyroid tissue that has metastasized to central compartment nodes or invaded visceral structures.

CONCLUSION

By correlating anatomic description, medical illustrations, surgical photos, and scans, we have attempted to clarify the reasons for foci of increased uptake following TT to improve the clinician's understanding of the anatomic complexity of this region.

Parathyroid adenoma arising within the sternocleidomastoid muscle: a rare complication of autotransplantation

A 19-year-old patient presented with slowly enlarging, painless, left-sided cervical mass. She had a background of multiple endocrine neoplasia 2B and had undergone a total thyroidectomy for medullary thyroid carcinoma during childhood. A cervical recurrence was therefore suspected. Ultrasonographic and MRI examination revealed a well-defined lesion within the left sternocleidomastoid muscle. Further evaluation with sestamibi and single-photon emission CT revealed elevated tracer uptake within the lesion. Cytological analysis, following ultrasound-guided sampling, revealed absent staining for calcitonin and blood samples confirmed a normal serum calcitonin level; however, the serum parathyroid hormone level was elevated. Overall, summative findings were consistent with a diagnosis of a parathyroid adenoma arising within the left sternocleidomastoid muscle. Given that this is not a location for a physiological parathyroid tissue, the adenoma might have arisen within the autotransplanted parathyroid tissue, injected into the muscular sheath during thyroidectomy. The clinical, radiological and pathological features are considered in this article.

Thyroid computed tomography imaging: pictorial review of variable pathologies

Abstract

Focal and diffuse thyroid abnormalities are commonly encountered during the interpretation of computed tomography (CT) exams performed for various clinical purposes. These findings can often lead to a diagnostic dilemma, as the CT reflects the nonspecific appearances. Ultrasound (US) examination has a superior spatial resolution and is considered the modality of choice for thyroid evaluation. Nevertheless, CT detects incidental thyroid nodules (ITNs) and plays an important role in the evaluation of thyroid cancer.

In this pictorial review, we cover a wide spectrum of common and uncommon, incidental and non-incidental thyroid findings from CT scans. We also discuss the most common incidental thyroid findings, best practices for their evaluation, and recommendations for their management. In addition, we explore the role of imaging in the assessment of thyroid carcinoma (before and after treatment) and preoperative thyroid goiter, as well as localization of ectopic and congenital thyroid tissue.

Teaching Points

• Thyroid disorders tend to have non-specific CT appearances.

• ITNs are common on neck CT.

• ITN management depends on nodule size, age, health status, lymphadenopathy, and invasion.

• CT is used in assessment of cancer extension, mass effect, invasion, and recurrence.

• CT plays a role in preoperative planning in patients with symptomatic goiter.

Feasibility Study of a Contrast-Enhanced Multi-Detector CT (64 Channels) Protocol for Papillary Thyroid Carcinoma: The Influence of Different Scan Delays on Tumor Conspicuity

BACKGROUND

Recently, a number of studies have advocated the diagnostic benefit of contrast-enhanced computed tomography (CECT) in the current ultrasound (US)-based preoperative evaluation of thyroid cancer. However, no study has been conducted to optimize a CECT protocol focusing on tumor conspicuity using a multi-detector CT scanner. This study aimed at determining the optimal scan delay for increased CT attenuation differences between thyroid cancer and parenchymal background using a biphasic CECT examination.

METHODS

This study retrospectively enrolled 84 patients (M:F = 7:77; Mage = 44.8 ± 10.9 years) with 87 papillary thyroid carcinomas (Msize = 14.1 mm) who consecutively underwent US and CECT examination prior to surgery. In each patient, CT scanning was taken twice-once with a 40-second delay and once with a 70-second delay-using a 64-channel multi-detector scanner. After obtaining the mean attenuation value (MAV) of the thyroid cancer and the ipsilateral parenchyma by drawing regions of interest on the CECT images based on their cytopathologic results and US findings, the parenchyma-cancer differences (PCD) between the early and delayed scans were simply compared using a paired t-test. Then, the mean differences in the MAVs of the thyroid cancer and ipsilateral parenchyma (hereafter abbreviated as Group) between the early and delayed scans (abbreviated as Time) were compared after adjusting for the other factors that significantly affected MAVs, such as concentration of iodinated contrast medium (abbreviated as CCM) and size of thyroid cancer (abbreviated as Size) using a repeated-measures general linear model.

RESULTS

Because the ipsilateral parenchyma exhibited significantly higher attenuation on the early scan and further decline on the delayed scan compared with thyroid cancer (p < 0.001), the PCD for thyroid cancer was significantly better with a 40-second scan delay than a 70-second delay (58.8 ± 36.6 Hounsfield units [HU] vs. 40.4 ± 25.6 HU; p < 0.001). Similar results were obtained from the repeated-measures general linear model that considered the effects of CCM, Size, Group, and Time, and the interaction of Group and Time.

CONCLUSION

Based on this CECT study that adjusted for the effects of CCM and size on MAV, early scans (e.g., 40-second scan delay) are helpful for improving the tumor conspicuity of thyroid cancer on CECT images.

Sonographic scoring of solid thyroid nodules: effects of nodule size and suspicious cervical lymph node

Introduction

Ultrasound is the most frequently used imaging method to evaluate thyroid nodules. Sonographic characteristics of thyroid nodules which are concerning for malignancy are important to define the need for fine needle aspiration biopsy or open surgery.

Objective

To evaluate malignancy risk of solid thyroid nodules through sonographic scoring. The effects of nodule size ≥2 cm and associated pathologic cervical lymph node in scoring were examined in addition to generally excepted suspicious features.

Methods

Medical data of 123 patients underwent thyroid surgery were reviewed, and 89 patients (58 females, 31 males) were included in the study. The presence and absence of each suspicious sonographic feature of thyroid nodules were scored as 1 and 0, respectively. Total ultrasound score was obtained by adding the positive ultrasound findings. Differently from the literature, nodule size ≥2 cm and associated pathologic cervical node were added in scoring criteria. The diagnostic performance of nodule characteristics for malignancy and the effect of total US score to discriminate malignant and benign disease were calculated.

Results

A significant relationship was found between malignancy and hypoechogenity, border irregularity, intranodular vascularity, and microcalcification (p < 0.05). Pathologic cervical node was observed predominantly in association with malignant nodules. Positive predictive value of suspicious cervical node for malignancy was 67%, similar to microcalcification. Nodule size ≥2 cm was not distinctive for diagnosis of malignancy. The number of suspicious sonographic features obtained with receiver operating characteristic analysis to discriminate between malignant and benign disease was three.

Conclusion

Sonographic scoring of thyroid nodules is an effective method for predicting malignancy. The authors suggest including associated pathologic node in the scoring criteria. Further studies with larger cohorts will provide more evidence about its importance in sonographic scoring.

Parathyroid adenoma causing spontaneous cervical hematoma: two case reports

BACKGROUND

Although spontaneous rupture of a cervical parathyroid adenoma with extracapsular hemorrhage is rare, it may cause cervical and mediastinal hematoma, leading to potentially fatal consequences.

CASE PRESENTATION

The first case was a 76-year-old Asian female who presented with pharyngeal discomfort and anterior chest ecchymosis. Endoscopic investigation showed submucosal hemorrhage in the pharynx and larynx. The second case was a 62-year-old Asian male who presented with anterior chest ecchymosis and suspected of a ruptured blood vessel. Both cases were diagnosed parathyroid adenoma with extracapsular bleeding by hypercalcemia, high levels of intact parathyroid hormone and presence of a nodule behind the thyroid. Both cases were treated with excision of tumor 7 months after initial presentation. After surgery, serum calcium and parathyroid hormone levels had decreased to normal level in both cases.

CONCLUSION

Extracapsular bleeding of a parathyroid adenoma should be considered in the differential diagnosis of non-traumatic neck hematoma.

The thyroid: review of imaging features and biopsy techniques with radiologic-pathologic correlation

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

Gamma probe-assisted excision of an ectopic parathyroid adenoma located within the thymus: case report and review of the literature

Primary hyperparathyroidism due to parathyroid adenomas may be associated with ectopic parathyroid gland localization in 20-25% of the patients. We report herein the excision of an ectopic parathyroid adenoma which was detected in the thymus gland by gamma probe intraoperatively. A 38-year-old patient presented to our clinic with a history of bilateral nephrolithiasis, chronic hypercalcaemia, and PTH elevation. A combination of Technetium-99 m sestamibi scintigraphy and Computed Tomography scan of the chest and neck revealed an ectopic parathyroid adenoma of 8.5 mm in its greatest dimension. The patient underwent sternotomy and the adenoma was found within the right lobe of the thymus gland with the intraoperative use of gamma probe. PTH detection and frozen biopsy were performed during surgery and confirmed the successful excision of the adenoma, while mild hypocalcaemia was noticed postoperatively. We conclude that accurate preoperative and intraoperative localization of an ectopic parathyroid adenoma is crucial to successful surgery. The use of at least two diagnostic modalities before surgical excision minimizes the risk of re-operation for recurrent hyperparathyroidism, while the intraoperative use of gamma probe offers a significant advantage over conventional techniques by reducing surgical time, morbidity and/or complications associated with surgical exploration.

Sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma

OBJECTIVES

The purpose of this study was to determine the sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma.

METHODS

This retrospective study included 36 pathologically proven follicular carcinomas (5 widely invasive and 31 minimally invasive) and 52 follicular adenomas in 88 patients who underwent thyroid surgery. We analyzed the sonographic features of each tumor, including maximum diameter, peripheral halo, echogenicity, echo texture, calcifications, and nodularity. The frequencies of the sonographic features were compared by χ(2) and Fisher exact tests between follicular adenomas and carcinomas. The relative risk of malignancy was evaluated by logistic regression analysis.

RESULTS

Predominantly solid contents, hypoechoic echogenicity, a heterogeneous echo texture, the presence of calcifications, and an absent or irregular thick halo were associated with follicular carcinoma (P < .05). Logistic regression analysis demonstrated that predominantly solid contents, a heterogeneous echo texture, and the presence of calcifications were associated with significant increases in the relative risk of follicular carcinoma (odds ratios, 9.4, 24.9, and 25.6, respectively; P < .01).

CONCLUSIONS

Sonography could provide useful information for differentiating follicular carcinoma from follicular adenoma.

Ultrasonographic features associated with malignancy in cytologically indeterminate thyroid nodules

CONTEXT

Thyroid nodules with indeterminate cytology usually are treated with surgery, but most are benign. Neck ultrasonography has varied results in predicting malignancy.

OBJECTIVE

To evaluate the predictive value of ultrasonography and the frequency of malignancy in patients who had indeterminate thyroid nodules.

DESIGN

Retrospective study.

SETTING

University hospital.

PATIENTS

There were 78 patients who had thyroid nodules that were diagnosed on cytology (fine needle aspiration) as a follicular lesion (atypia of undetermined significant) or follicular neoplasm. Ultrasonography was available in 69 patients (88%).

INTERVENTION AND MAIN OUTCOME MEASURES

Diagnostic fine needle aspiration (cytology), ultrasonography, and surgical pathology of thyroid nodules.

RESULTS

Fine needle aspiration was indeterminate in all patients, with follicular lesions in 60 patients (77%) and follicular neoplasm in 18 patients (23%). Ultrasonography showed micro calcification in 6 patients (9%), irregular border in 15 patients (22%), size ≥ 3 cm in 31 patients (45%), and hypoechogenicity in 43 patients (62%). Surgical pathology showed that the nodules were benign in 50 patients (64%) and malignant in 28 patients (36%). Malignancy was significantly associated with male sex (relative risk, 2.3), solid nodule structure (relative risk, 2.6), and irregular border (relative risk, 3.6). Compared with other ultrasonographic characteristics, irregular borders had the highest specificity (93%), positive predictive value (80%), and accuracy (78%) for malignancy.

CONCLUSIONS

The frequency of malignancy is high in indeterminate thyroid nodules. Based on the limited accuracy or predictive value of ultrasonographic risk factors, surgery is the treatment of choice for indeterminate thyroid nodules.

Pitfalls in the staging of cancer of thyroid

Thyroid cancer includes several neoplasms originating from the thyroid gland-from indolent and curable histologies of differentiated thyroid carcinoma to aggressive anaplastic thyroid carcinoma. Differentiation of thyroid nodules is problematic on CT and MR imaging unless there is evidence of extrathyroidal extension. Evaluation of regional lymph nodes is often performed clinically or with ultrasound. The retropharyngeal and mediastinal lymph nodes are better evaluated by CT and MR imaging. Nuclear scintigraphy is useful for staging and treatment of distant metastasis in differentiated thyroid carcinoma. PET may have a role in aggressive cancers. Accurate staging affects surgical management and subsequent therapy.

Recombinant human thyrotropin-aided radioiodine therapy in tracheal obstruction by an invading well-differentiated thyroid carcinoma

Papillary thyroid carcinomas (PTCs) usually extend to lymph nodes in the neck and mediastinum. Rarely, they invade the neighboring upper airway anatomical structures. We report a 56-year-old woman who presented with symptoms of upper airway obstruction. Imaging studies revealed a lesion derived from the thyroid which invaded and obstructed the trachea, which appeared to be a highly differentiated PTC. Total thyroidectomy was performed, with removal of the endotracheal part of the mass along with the corresponding anterior tracheal rings. Two months later, a whole body I(131) scan after recombinant human thyroid-stimulating hormone (rh-TSH) administration was performed and revealed a residual mass in upper left thyroid lobe. Subsequently, 150 mCi I(131) were given following rh-TSH administration. Nine months later, there was no sign of residual tumor. This case is the first one reported in the literature regarding rh-TSH administration prior to RAI ablation in a PTC obstructing the trachea.

Diagnosis and management of parathyroid cancer

Parathyroid cancer is rare, but often fatal, as preoperative identification of malignancy against the backdrop of benign parathyroid disease is challenging. Advanced genetic, laboratory and imaging techniques can help to identify parathyroid cancer. In patients with clinically suspected parathyroid cancer, malignancy of any individual lesion is established by three criteria: demonstration of metastasis, specific ultrasonographic features, and a ratio >1 for the results of third-generation:second-generation parathyroid hormone assays. Positive findings for all three criteria dictate an oncological surgical approach, as appropriate radical surgery can achieve a cure. Mutation screening pinpoints associated conditions and asymptomatic carriers. Molecular profiling of tumour cells can identify high-risk features, such as differential expression of specific micro-RNAs and proteins, and germ line mutations in CDC73, but is unsuitable for preoperative assessment owing to the potential risks associated with biopsy. A validated, histopathology-based prognostic classification can identify patients in need of close follow-up and adjuvant therapy, and should prove valuable to stratify clinical trial cohorts: low-risk patients rarely die from parathyroid cancer, even on long-term follow-up, whereas 5-year mortality in high-risk patients is around 50%. This insight has improved the approach to parathyroid cancer by enabling risk-adapted surgery and follow-up.

Diagnostic performance of planar scintigraphy using ⁹⁹mTc-MIBI in patients with secondary hyperparathyroidism: a meta-analysis

OBJECTIVE

Parathyroid scintigraphy using (99m)Tc-MIBI is not currently considered a valuable diagnostic tool for the localization of involved glands in patients with secondary hyperparathyroidism (SHPT). However, published data about its diagnostic accuracy are discordant and a meta-analysis about this topic is still lacking. The aim of our study is to meta-analyze the published data about the diagnostic performance of (99m)Tc-MIBI parathyroid scintigraphy in patients with SHPT.

METHODS

A comprehensive computer literature search of studies published in PubMed/MEDLINE, Scopus and Embase databases through September 2011 and regarding the diagnostic accuracy of (99m)Tc-MIBI parathyroid scintigraphy in patients with SHPT was carried out. Only articles in English language in which at least 10 patients with SHPT underwent planar (99m)Tc-MIBI parathyroid scintigraphy were selected. Pooled sensitivity, pooled specificity and area under the ROC curve on a per lesion-based analysis were calculated to measure the diagnostic accuracy of (99m)Tc-MIBI parathyroid scintigraphy in SHPT patients.

RESULTS

Twenty-four studies comprising 471 patients were included in this meta-analysis. The pooled sensitivity and specificity of (99m)Tc-MIBI parathyroid scintigraphy in detecting hyperplastic glands in SHPT patients were 58 % [95 % confidence interval (95 % CI) 52-65 %] and 93 % (95 % CI 85-100 %), respectively, on a per lesion-based analysis. Area under ROC curve was 0.75.

CONCLUSIONS

In patients with SHPT and diffuse or nodular hyperplasia, planar parathyroid scintigraphy using (99m)Tc-MIBI has demonstrated an inadequate diagnostic accuracy. Therefore, it should not be considered as a first-line diagnostic imaging method in the pre-surgical detection of hyperplastic parathyroid glands.

Parathyroid cysts: a clinical and radiological challenge

Parathyroid cysts are rare causes of neck swelling accounting for 0.6% of thyroid and parathyroid lesions. They may be functional, resulting in the release of parathyroid hormone, or non-functional. Non-functional cysts may be cosmetically unacceptable or cause dysphagia, dyspnoea or recurrent laryngeal nerve palsy as a result of compression. This article presents a young woman who was diagnosed with a thyroid cyst both on examination and imaging. However, the final histology confirmed this to be parathyroid in origin and this should be considered in the differential of such neck swellings.

Thyroid paragangliomas are locally aggressive

BACKGROUND

Thyroid paraganglioma (TP) is a very rare neoplasm that can be misdiagnosed. We evaluated the clinical and pathologic characteristics of three patients with TP.

PATIENT FINDINGS

The records of all patients from 1981 to 2008 who had thyroidectomy with a final histologic diagnosis of TP were retrieved, and histology was reviewed by a single pathologist. Head and neck paragangliomas arising outside of the thyroid were excluded. TP accounted for 3 of all 6782 (0.04%) patients undergoing thyroidectomy during three decades. One patient has been previously reported and will not be discussed. In the remaining two patients and a surgical pathology consult case that we also describe herein, the mean age at diagnosis was 56 years (40-67) and two patients were men. Presenting features were indicative of advanced local invasion, including stridor, tracheal invasion, compression of the great vessels, and hemoptysis. The diagnosis of TP was not suspected preoperatively; in two patients, fine-needle aspiration (FNA) cytology was inadequate for diagnosis because of excessive blood. Intraoperative frozen section analysis suggested medullary thyroid cancer in two patients and oncocytic (Hurthle) cell carcinoma in one patient. Local invasion was common, requiring concurrent tracheal resection in two of three patients, and present histologically in all three patients. In all three cases, immunohistochemical analysis was negative for cytokeratin AE1/3, calcitonin, and thyroglobulin but positive for S100, highlighting sustentacular cells. After resection of a large TP with tracheal and vascular invasion, a 67-year-old woman experienced a 7-year disease-free interval.

CONCLUSIONS

Primary TP is indeed rare. It does occur in men, frequently presents with compressive symptoms, and is typically locally aggressive, but does not appear to cause symptoms suggestive of catecholamine excess. Despite invasion of adjacent structures, aggressive resection can achieve a long disease-free interval.

FDG-PET/CT and parathyroid carcinoma: Review of literature and illustrative case series

Parathyroid cancer is an uncommon malignant cancer and is associated with a poor prognosis. The staging of parathyroid cancer represents an important issue both at initial diagnosis and after surgery and medical treatment. The role of positron emission tomography/computed tomography (PET/CT) with 18F-Fluorodeoxyglucose (18F-FDG) as an imaging tool in parathyroid cancer is not clearly reported in the literature, although its impact in other cancers is well-defined. The aim of the following illustrative clinical cases is to highlight the impact of PET/CT in the management of different phases of parathyroid cancer. We describe five patients with parathyroid malignant lesions, who underwent FDG PET/CT at initial staging, restaging and post-surgery evaluation. In each patient we report the value of PET/CT comparing its findings with other common imaging modalities (e.g., CT, planar scintigraphy with 99mTc-sestamibi, magnetic resonance imaging) thus determining the complementary benefit of FDG PET/CT in parathyroid carcinoma. We hope to provide an insight into the potential role of PET/CT in assessing the extent of disease and response to treatment which are the general principles used to correctly evaluate disease status.

Imaging of the thyroid and parathyroid glands

Current multimodal imaging techniques offer practicing providers the adequate framework to plan and accomplish care for patients with thyroid and parathyroid disorders. Available imaging modalities include ultrasonography (US), nuclear scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI). US remains the most cost-effective and the safest approach for the initial evaluation of the thyroid gland. Parathyroid subtraction scintigraphy provides localization of pathologic parathyroid glands with the greatest sensitivity. Localizing imaging studies allow for surgical planning with minimal risk and morbidity to the patient. CT scan and MRI play an adjunctive role in the further characterization of neck pathology.

Squamous cell carcinoma of the thyroid gland: primary or secondary disease?

OBJECTIVE

To review the aetiopathogenesis, clinical characteristics, immunohistochemical profile, prognosis and treatment options for primary thyroid squamous cell carcinoma, and to compare it with squamous cell carcinoma metastatic to the thyroid, thus providing the reader with a framework for differentiating primary and secondary disease.

METHOD

Review of English language literature from the past 25 years.

SEARCH STRATEGY

A search of the Medline, Embase and Cochrane databases (April 1984 to April 2009) was undertaken to enable a comprehensive review.

RESULTS

After applying strict criteria for the diagnosis of primary thyroid squamous cell carcinoma, 28 articles were identified reporting 84 cases. When reviewing secondary thyroid squamous cell carcinoma, we only analysed cases of squamous cell carcinoma metastatic to the thyroid gland, and found 28 articles reporting 78 cases.

CONCLUSION

It is possible to differentiate between primary and secondary thyroid squamous cell carcinoma, on the basis of combined evidence from clinical examination and endoscopic, pathological and radiological evaluation. Such differentiation is important, as the prognosis for primary squamous cell carcinoma is uniformly poor irrespective of treatment, and the most suitable option may be supportive therapy. Treatment for secondary squamous cell carcinoma of the thyroid varies with the site and extent of spread of the primary tumour.

Focus on parathyroid carcinoma

Parathyroid carcinoma is a malignant neoplasm affecting 05-2 per cent of all patients with primary hyperparathyroidism that was first described by de Quevain in 1904. To day it continues to defy diagnosis and treatment. It is difficult to diagnose in part because of its rarity, lack of definitive diagnostic markers and overlapping clinical features of benign primary hyperparathyroidism. As a result initial surgical treatment is inadequate essentially leading to disease recurrence where complete cure is unlikely. En bloc surgical resection remains the only curative treatment, and high priorities are improving diagnostic methods, and clinical staging for resection once the disease is suspected. Margin status at resection is related to prognosis. Thus, a trend towards aggressive surgical management has improved outcomes. The recurrence rate of parathyroid carcinoma is as high as 80% with survival rates <50% at 10 years. Results of chemotherapy are disappointing. However, recent trials using radiation therapy are promising, but require further study.

Locally advanced thyroid cancer: can CT help in prediction of extrathyroidal invasion to adjacent structures?

OBJECTIVE

The purpose of this study was to determine the diagnostic accuracy of CT for detecting extrathyroidal invasion of thyroid cancer to adjacent structures.

MATERIALS AND METHODS

Eighty-four patients (19 men, 65 women; age range, 19-84 years; mean, 54.2 +/- 15.4 years) with 86 malignant tumors of the thyroid with extracapsular extension (37 T3, 49 T4) were retrospectively enrolled in this study. Two radiologists independently evaluated the CT findings of invasion of thyroid cancer into the trachea, esophagus, common carotid artery, internal jugular vein, and recurrent laryngeal nerve. These results were compared with the surgical and histopathologic findings.

RESULTS

The mean sensitivity, specificity, and accuracy of CT were as follows: 59.1%, 91.4%, and 83.2% for tracheal invasion; 28.6%, 96.2%, and 90.7% for esophageal invasion; 75.0%, 99.4%, and 98.8% for invasion of the common carotid artery; 33.3%, 98.8%, and 97.1% for invasion of the internal jugular vein; and 78.2%, 89.8%, and 85.5% for invasion to the recurrent laryngeal nerve. Interobserver agreement was moderate to good in the five categories of extrathyroidal invasion with a mean kappa value of 0.65 (range, 0.49-0.77).

CONCLUSION

Although the effectiveness is limited by low sensitivity, CT may be a valuable tool for evaluation of extrathyroidal invasion of thyroid cancer to adjacent structures.

Parathyroid carcinoma

Parathyroid carcinoma is a rare tumor that is prone to recurrence and poor local-regional control. Despite advances in technologies that have shown promise for accurate diagnosis, the mainstay of initial diagnosis remains pathologic analysis and clinical assessment. A surgeon's intraoperative analysis is important in managing patients with parathyroid carcinoma. If parathyroid carcinoma is suspected intraoperatively, a more aggressive surgical strategy should be implemented. This article presents a case series and summary of the existing parathyroid carcinoma literature.

Parathyroid carcinoma

Parathyroid carcinoma is a rare endocrine malignancy. The reported incidence is from 0.5 to 5% of primary hyperparathyroidism cases in various series. The cause is unknown, but clinical correlations with different genetic syndromes exist. Mutations in the HPRT2 gene seem to play a significant role in the pathogenesis of this disease. Men and women are equally affected, usually in the fourth or fifth decade of life. Most patients will present with signs and symptoms of hypercalcaemia. Cases of non-functioning carcinoma are exceedingly rare. Surgical resection is the most effective method of treatment and palliation. A significant proportion of patients will experience recurrence, and will need further surgical and, eventually, medical management of hypercalcaemia. The disease is progressive but slow growing. Most patients will require multiple operations to resect recurrent disease. The main cause of morbidity and mortality is the sequela of uncontrolled chronic hypercalcaemia rather than tumour burden. The current paper will review the epidemiology, pathogenesis, clinical presentation and diagnostic work-up of this disease. Surgical management in different scenarios is reviewed in detail, followed by other types of treatment and management of incurable disease.

Thyroid follicular neoplasms: can sonography distinguish between adenomas and carcinomas?

PURPOSE

The purpose of this study was to determine whether sonography (US) can usefully differentiate thyroid follicular adenoma (FA) and follicular carcinoma (FC).

METHODS

This retrospective study included 60 pathologically proven FAs and 66 FCs in 123 consecutive patients (17 males and 106 females) with a mean age of 47 +/- 13 years, (17-73 years) who underwent thyroid surgery. We analyzed US features of each nodule, including maximum diameter, echogenicity, composition, presence of calcification, margins, and presence of halo. The frequencies of each US feature were compared by using the chi(2) test or Fisher's exact test between FAs and FCs. The relative risk of malignancy was evaluated by logistic regression analysis.

RESULTS

Isohypoechoic echogenicity, predominantly solid or mixed echotexture, and presence of microcalcifications or rim calcifications were associated with FC (p < 0.05). Logistic regression analysis demonstrated that predominantly solid or mixed echotexture and microcalcifications or rim calcifications were associated with significant increases in relative risk for FC (odds ratio 8.1 and odds ratio 13.5, respectively, p < 0.01).

CONCLUSIONS

The US features of isohypoechoic echogenicity, predominantly solid or mixed echotexture, and microcalcifications or rim calcifications are more common in FC than in FA.