Scintigraphically detected "hot" thyroid nodules in the specimens from patients of the Thyroid Disease Clinic in Gda'nsk--clinico- histopathological analysis

A group of 153 patients with scintigraphically detected autonomic "hot" nodules of the thyroid has been subjected to clinical and histopathological analysis. Substantial part of these patients (30.1%) had hyperthyroidism, partly (in 19.9% of cases) in the form of the thyrocardiac syndrome. A most frequent histopathological lesion found within "hot" nodules was follicular adenoma. The occurrence of malignancy in the form of highly differentiated thyroid carcinoma was observed in 2.6% of cases. The incidence of thyroid carcinoma within "hot" nodules was in our material only two and half times smaller than in a previously analyzed group of patients with "cold" nodules of the thyroid.     

Scintigrams of the thyroid gland; the diagnosis of morphologic abnormalities with I131

Functioning thyroid tissue containing sufficient radioiodine can be visualized by scanning the gland with a directional scintillation counter.(4) This visual representation of the gland is called a "scintigram." Scintigrams have been invaluable in the detection and study of both "toxic" and non-functioning nodules, diffuse enlargement in hyperthyroidism and the subsequent reduction in gland size after treatment, carcinoma, and aberrant thyroid tissue.     

Inappropriate indication for surgical treatment of goiter diagnosed as hyperactive

Aim of this report is a stress of over-hasty classification to the surgical treatment of goiter diagnosed as hyperactive. The authors suppose that the cause of such errors is an incorrect interpretation of the current diagnostic tests, especially scintigraphy, and not very careful clinical evaluation of cases diagnosed as hyperthyroidism, being vegetative neurosis which is sometimes accompanied by the arterial blood hypertension. Examples of patients misclassified from the surgical treatment after proper diagnosis based on the clinical symptoms confirmed with thyroid gland diagnostic test are given. The authors stress that the detailed knowledge on the clinical course of hyperthyroidism and proper interpretation of the diagnostic tests help to avoid such errors.     

SCINTIGRAMS OF THE THYROID GLAND—The Diagnosis of Morphologic Abnormalities with I131

Functioning thyroid tissue containing sufficient radioiodine can be visualized by scanning the gland with a directional scintillation counter.⁴ This visual representation of the gland is called a “scintigram.” Scintigrams have been invaluable in the detection and study of both “toxic” and non-functioning nodules, diffuse enlargement in hyperthyroidism and the subsequent reduction in gland size after treatment, carcinoma, and aberrant thyroid tissue.     

METASTATIC CARCINOMA OF THE THYROID GLAND AS THE INITIAL MANIFESTATION OF THE DISEASE

During the past 38 years, 260 patients with thyroid carcinoma have been operated upon at the University of California Hospital. In 26 of these patients the first symptom was a mass distant from the thyroid gland, and the gland was considered normal on clinical examination.In all but three of the 26 cases a small carcinoma of the thyroid gland was observed at operation or in pathological examination.Radical neck dissection with either total lobectomy or total thyroidectomy would seem to be the operation of choice in the treatment of these patients.The ultimate prognosis, even in the presence of metastases, is relatively good.Primary carcinoma of the thyroid gland should be considered in the presence of tumors of the side of the neck even in the absence of palpable nodules in the gland itself.     

Extra-articular features in early rheumatoid disease.

One hundred and two patients who presented with rheumatoid disease within the first year of onset were studied prospectively every four months for a mean 4.5 years to assess the incidence of extra-articular features. The features that seemed to be common in the early stages included hand-muscle wasting, carpal tunnel syndrome, lymphadenopathy, non-specific ankle swelling, and rheumatoid nodules, and to a lesser extent hepatomegaly, being underweight, conjunctivitis, skin transparency, and a palpable thyroid gland. Those features which seldom occurred early included scleromalacia, temporal artery inolvement, salivary gland enlargement, distal-motor neuropathy, splenomegaly, digital vasculitis, and pulmonary and cardiac complications. Being underweight indicated a significantly more severe outcome.     

Hyperthyroidism in the elderly: aspecific signs may cause a delay in diagnosis

The clinical manifestations of thyroid diseases in the elderly are often atypical and can easily be attributed to other medical conditions or 'normal aging'. Two nursing home patients with hyperthyroidism are described. Due to the atypical presentation of the thyroid disease their complaints were attributed to other conditions. In both patients there was a significant delay in diagnosis and treatment of hyperthyroidism. In elder patients signs and symptoms of thyreotoxicosis are frequently related to cardiovascular, gastrointestinal and neuropsychiatric disorders. Most often occur atrial fibrillation, worsening of cardiac failure and angina pectoris, weight loss, anorexia, constipation, cognitive impairment and delirium. Delay of diagnosis and treatment of hyperthyroidism may be potentially harmful to the patient. Untreated thyreotoxicosis may lead to serious cardiovasculair complications (particularly cardiac failure and cerebrovascular accidents), mental deterioration and osteoporosis. In elder people with unexplained and vague signs and symptoms thyroid function should always be checked. The TSH assay is a very accurate diagnostic test for screening thyroid function. A normal TSH indicates euthyroidism with an accuracy of almost 100%. The medical treatment for hyperthyreoidism in the elderly are antithyroid drugs. When an euthyroid state is rendered, suppletion with L-thyroxine may be nessecary. Radioactive iodine treatment is preferred in some cases though there may be practical difficulties with the application of this treatment in nursing home patients because temporary isolation is necessary.     

Thyroid function in patients during long-term treatment with amiodarone]

Thyroid function was evaluated in 31 patients with disturbances of heart rhythm both before and after 13 months of treatment with amiodarone. An increase in blood serum T4 concentration and transient increase (only during the first three months of treatment) in TSH concentration have been observed in almost all the patients studied. Clinically evident form of hyperthyroidism was found only in one female patient. In two patients the changes in hormone concentrations suggesting hyperthyroidism were not accompanied by clinical manifestations, and in four patients there was no clinical hypothyroidism despite hormone levels suggesting such a state. In addition to the determinations of T3, T4 and TSH also the results of TRH-TSH test played an important role in diagnosing both hypo- and hyperthyroidism.     

Intermittent hyperthyreosis -- a heat stress syndrome.

Intermittent hyperthyreosis occurs under various forms of stress, especially heat stress. The clinician may diagnose such cases as masked or apathetic hyperthyroidism or "forme fruste" hyperthyreosis or thyroid autonomy. As most routine and standard tests may here yield inconsistent results, it is the patients' anamnesis which may provide the clue. Our Bioclimatology Unit has now seen over 100 cases in which thyroid hypersensitivity towards heat was the most prominent syndrome: 10-15% of weather-sensitive patients are affected. The patients complain before or during heat spells of such contradictory symptoms as insomnia, irritability, tension, tachycardia, palpitations, precordial pain, dyspnoe, flushes with sweating or chills, tremor, abdominal pain or diarrhea, polyuria or pollakisuria, weight loss in spite of ravenous appetite, fatigue, exhaustion, depression, adynamia, lack of concentration and confusion. Determination of urinary neurohormones allows a differential diagnosis, intermittent hyperthyreosis being characterized by three cardinal symptoms: 1. tachycardia -- every case with more than 80 pulse beats being suspect (not specific); 2. urinary histamine -- every case excreting more than 90 mug/day being suspect. Again the drawback of this test is its lack of specificity, as histamine may also be increased in cases of allergy and spondylitis; 3. urinary thyroxine -- every case excreting more than 20 mug/day T-4 being suspect. This is the only specific test. Therapy should make use of lithium carbonate and beta-blockers. Propyl thiouracil is rarely required.     

An unusual ‘bow tie’ image in pacemaker implantation

Upper venous system anatomic variations may cause difficulties during cardiac pacemaker implantation. Persistent left superior vena cava (PLSVC) and absent right superior vena cava could be an arrhythmogenic source of atrial arrhythmias and cardiac conduction disease. We represent dual-chamber pacemaker implantation in a patient with a very rare upper venous system anomaly, paroxysmal atrial fibrillation, sick sinus syndrome, that cause unusual fluoroscopic image.     

Unusual Case of Amiodarone-Induced Thyrotoxicosis “Illicit” use of a Technetium Scan to Diagnose a Transiently Toxic Thyroid Nodule

ObjectiveTo present an unusual case of amiodarone-induced thyrotoxicosis (AIT) associated with an autonomously functioning thyroid nodule, which was detected by means of a technetium scan; review the existing literature regarding the association of AIT with autonomous thyroid nodules; and explore the use of radioisotope imaging studies in patients with AIT.MethodsWe describe a 62-year-old man with paroxysmal atrial fibrillation, receiving long-term amiodarone therapy, who was referred by his cardiologist for evaluation of abnormal thyroid function tests. He was found to have an unusual case of AIT, associated with an autonomously functioning thyroid nodule.ResultsThyroid function studies obtained by the patient’s cardiologist had shown a completely suppressed thyrotropin level and a free thyroxine level of 3.5 ng/dL. A 24-hour thyroid iodine 123 uptake and technetium Tc 99m pertechnetate scan revealed a “single, strong focus in the right thyroid lobe, with the rest of the thyroid gland...not well visualized.” Thyroid ultrasonography disclosed a single, well-defined 1.5-cm solid nodule. Repeated thyroid function studies revealed a normal thyrotropin level of 2.87 μIU/mL and a normal free thyroxine level of 2.4 ng/dL. The patient was managed conservatively with follow-up surveillance.ConclusionProspective studies should be performed to better ascertain the value of Tc 99m thyroid scanning in determining the cause of AIT. Until such studies have been completed, we suggest that nuclear studies are unlikely to be cost-effective for assessing all patients with AIT. One logical strategy would be to gain experience with scans in only those patients with known thyroid nodules, which have been detected during physical examination or by ultrasonography. The potential clinical utility of such an approach would be of considerable interest. (Endocr Pract. 2007;13:413-416)     

Ultrasonographic and scintigraphic studies of "hot" autonomic thyroid nodules

Scintigraphic and gammagraphic (gamma-camera) techniques have been applied in diagnosing "hot" non-TSH dependent thyroid nodules. On the basis of frequent uneven accumulation of isotopic tracer observed in scintigraphic studies it was concluded that the structure of these nodules is heterogeneous. In some cases paradoxical patterns have been obtained following the dynamic tests of suppression and stimulation of the thyroid: after the administration of thyroid preparations paranodular thyroid tissue appears, while TSH administration causes an increase in the iodine uptake by the nodule. Ultrasonographic and gamma-camera studies have been carried out in 50 cases of "hot" autonomic thyroid nodules previously diagnosed by scintigraphy. Ultrasonographic studies revealed a weaker echogenicity in some cases and an intensified echo in the other. Sometimes by using this technique it was possible to demonstrate the occurrence of heterogeneous structures suggesting a cystic degeneration of the nodule. Paranodular thyroid tissue, invisible in scintigraphic scanning, could usually be observed by applying gamma-camera. It was concluded that both gamma camera and ultrasonographic studies confirm heterogeneous structure of intranodular tissue producing paradoxical patterns in scintigraphic scanning, with the latter technique usually aiding the detection of paranodular thyroid tissue without the necessity of application of the TSH test.     

Autoimmune thyroid disease: new models of cell death in autoimmunity

Autoimmunity to thyroid antigens leads to two distinct pathogenic processes with opposing clinical outcomes: hypothyroidism in Hashimoto's thyroiditis and hyperthyroidism in Graves' disease. The high frequency of these diseases and easy accessibility of the thyroid gland has allowed the identification of key pathogenic mechanisms in organ-specific autoimmune diseases. In early investigations, antibody- and T-cell-mediated death mechanisms were proposed as being responsible for autoimmune thyrocyte depletion. Later, studies on apoptosis have provided new insights into autoimmune target destruction, indicating the involvement of death receptors and cytokine-regulated apoptotic pathways in the pathogenesis of thyroid autoimmunity.     

The pathology of the nodular goiter

Pathologic studies of thyroid nodules indicate that a definite percentage of nodular goiters are malignant, and that an even higher percentage are true neoplasms. Malignant tumors may arise from adenomas, involutionary nodules or possibly from nodules of the unclassified type. Some carcinomas of the thyroid gland are undoubtedly malignant processes from the start. Because of the high incidence of neoplasms, benign and malignant, in a group of single nodules of the thyroid gland, the presence of such nodules should warrant radical resections of the involved lobe and adjacent isthmus. The high incidence of epithelial growth activity in nodular involutionary goiters may revise the accepted practice of removing non-toxic nodular goiters only when clinical evidence of growth or local pressure is present.     

The prevalence of incidentaloma--asymptomatic thyroid nodules in the Tricity (Gdansk, Sopot, Gdynia) population

INTRODUCTION: The increased sensitivity of imaging devices raised number of incidentally discovered lesions in various organs of the human body. Thyroid gland is one of them. Reported prevalence of ultrasonographically detected thyroid nodules (incidentalomas) in general population ranges from 5.2 to 67.0%. Our study demonstrated occurrence of this clinical problem in the general population of the Tricity. MATERIAL AND METHODS: 135 healthy adults (95 women and 40 men) were examined. Neck palpation, ultrasonographic examinations of thyroid gland and serum tyreotropin (TSH) level measurement were made. RESULTS: In 8.9% of examine (12/135) persons nodules were palpable whereas in 14.8% (20/135) they were detectable only in ultrasonographic examination. Altogether thyroid ultrasound and palpation revealed nodules in 23.7% (32/135) of all cases. Multiple nodules were present in 12.0% of the cases. The pathology was more common in the elderly and in women. TSH serum level was within normal range in all cases of incidentaloma with otherwise normal thyroid gland. CONCLUSIONS: Prevalence of thyroid gland nodules (palpation--8.9% plus ultrasonography--14.8%) in healthy population of Gdansk, Gdynia and Sopot is close to data reported in southern Finland (27.0%) and Belgium (19.0%), where iodine deficiency is small, like in the Tricity area. The revealed lesions were over two times more frequent in the female population. Most of the nodules were not palpable.     

Thyroid cancer in patients with hyperthyroidism

Thyroid cancer can be associated with thyrotoxicosis caused by Graves' disease, toxic multinodular goiter, or autonomously functioning thyroid adenoma. The objective of this study was to summarize current evidence regarding the association of thyroid cancer and hyperthyroidism, particularly with respect to the type of hyperthyroidism found in some patients, and whether this affects the outcome of the patient. A PubMed search was performed up to August 2011. Articles were identified using combinations of the following keywords/phrases: thyroid cancer, papillary thyroid cancer, follicular thyroid cancer, medullary thyroid cancer, anaplastic thyroid cancer, hyperthyroidism, Graves' disease, auto-nomous adenoma, toxic thyroid nodule, and toxic multinodular goiter. Original research papers, case reports, and review articles were included. We concluded that the incidence, as well as the prognosis of thyroid cancer associated with hyperthyroidism is a matter of debate. It seems that Graves' disease is associated with larger, multifocal, and potentially more aggressive thyroid cancer than single hot nodules or multinodular toxic goiter. Patients with Graves' and thyroid nodules are at higher risk to develop thyroid cancer compared to patients with diffuse goiter. Every suspicious nodule associated with hyperthyroidism should be evaluated carefully.     

Melatonin prevents oxidant damage in various tissues of rats with hyperthyroidism

Impairment of thyroid functions brings about pathological changes in different organs of body. Findings of in vivo and in vitro studies indicate that thyroid hormones have a considerable impact on oxidative stress. Melatonin reduces oxidative damage through its free radical eliminating and direct anti-oxidant effects. The present study was undertaken to determine how a 3-week period of intraperitoneal melatonin administration affected oxidative damage caused in experimental hyperthyroidism in rat. The experimental animals were divided into 3 groups (control, hyperthyroidism, hyperthyroidism+melatonin). Malondialdehyde (MDA) and glutathione (GSH) levels were determined in different tissues. MDA levels in cerebral, liver and cardiac tissues in hyperthyroidism group were significantly higher than those in control and hyperthyroidism+melatonin supplemented groups (p<0.001). The highest GSH levels were observed in the group that was administered melatonin in addition to having hyperthyroidism (p<0.001). These results show that hyperthyroidism increased oxidative damage in cerebral, hepatic and cardiac tissues of rat. Melatonin supplementation may also suppress oxidative damage.     

Comparison between a shortened TRH-TSH test and thyroid suppression test in the diagnosis of hyperthyroidosis]

In a selected group of fifty-one persons suspected to be hyperthyroid the comparison between a shortened variant of TRH-TSH stimulation test and thyroid suppression test was made. In patients whose other functional tests gave no univocal results, the agreement between suppressibility of radioiodine uptake and TSH response in 90,2% of cases could be established. High degree of correlation between both parameters (coefficient V = 0.791) permits to regard these tests as practically equivaluablein giving evidence of dysregulation between pituitary and thyroid gland. In persons with TSH-dependent thyroid function, however, no correlation between numerical values of radioiodine uptake and TSH concentrations after stimulations was found.     

Gene expression profile in thyroid of transgenic mice overexpressing the adenosine receptor 2a

Mutations of the TSH receptor leading to constitutive activation of the cAMP cascade are responsible for the development of hot nodules, if arising in a somatic cell, and nonautoimmune hyperthyroidism, when occurring in a germinal cell. An animal model of constitutive activation of the thyroid cAMP cascade has been obtained by generating transgenic mice expressing the adenosine receptor (Tg-A2aR) under the control of the thyroglobulin promoter. These mice develop huge goiters and die prematurely due to hyperthyroidism induced cardiac failure. To identify new genes involved in the tumorigenic pathway of the thyroid, we designed a protocol using microarray technology to study the differential expression, between normal and transgenic thyroid, of +/-13,000 genes. A total of 360 genes or expressed sequence tags showed a strong modulation with background corrected values of fluorescence superior to 2-fold change. The modulated genes were classified according to their proposed gene ontology functions. Approximately half of them were up-regulated. The function of the majority of these genes in thyroid physiology is still to be determined. Some of them, like IGF-I or IGF binding protein 3 or 5, may play an important role in the development of thyroid nodules through paracrine mechanisms. This study demonstrates the feasibility of sequentially following the cascade of events leading to the formation of benign tumors such as hot thyroid nodule or hyperfunctional goiter.     

THE PATHOLOGY OF THE NODULAR GOITER

Pathologic studies of thyroid nodules indicate that a definite percentage of nodular goiters are malignant, and that an even higher percentage are true neoplasms. Malignant tumors may arise from adenomas, involutionary nodules or possibly from nodules of the unclassified type. Some carcinomas of the thyroid gland are undoubtedly malignant processes from the start. Because of the high incidence of neoplasms, benign and malignant, in a group of single nodules of the thyroid gland, the presence of such nodules should warrant radical resections of the involved lobe and adjacent isthmus. The high incidence of epithelial growth activity in nodular involutionary goiters may revise the accepted practice of removing non-toxic nodular goiters only when clinical evidence of growth or local pressure is present.