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PubMed1992

Non-suppressed thyroidal radioactive iodine uptake (RAIU) in thyrotoxic phase in a case of subacute thyroiditis with thyroid-stimulating antibodies (TSAb).

In this paper, we report a 49-year-old female with subacute thyroiditis who had thyroid-stimulating antibodies (TSAb) and thyroid-stimulation-blocking antibodies (TSBAb) in serum. Although she was in the thyrotoxic phase and TSH was suppressed in May, 1990, her radioactive iodine uptake (RAIU) was not suppressed (35.5%) and a thyroid scan disclosed a diffuse goiter with no defect. Serum assays revealed the presence of TSAb, but TSBAb were negative. In August, 1990, the right lobe became undetectable by thyroid scan when the RAIU was 20.7% with the TSH level remaining suppressed. At that time, TSAb were negative, while TSBAb were positive. When the RAIU was 31.1% in October, 1990, both thyroid lobes became visible and the TSH level was normalized. TSBAb became negative, and although TSAb reappeared it later became undetectable. These results indicate that the changes in the patient's thyroid scan and RAIU were attributable to the presence of TSAb.

Autoantibodies↗
PubMed1982

Syngeneic sensitization of mouse lymphocytes on monolayers of thyroid epithelial cells. III. Induction of thyroiditis by thyroid-sensitized T lymphoblasts.

During in vitro sensitization of CBA spleen lymphocytes on syngeneic monolayers of either thyroid epithelial cells (TEC) or fibroblasts, stimulation occurs, as assessed by thymidine incorporation and lymphoblast generation. When lymphoblasts generated on syngeneic TEC are injected either into thyroid lobes of intact CBA recipients or i.v., thyroiditis appears at least 21 days after injection. Thyroiditis is assessed by both optical and electron microscopic blind studies and by the presence of antibodies in the sera directed against mouse thyroglobulin. In contrast, control animals which received identical numbers of lymphoblasts generated on syngeneic fibroblasts behaved as normal. Thyroiditis was also induced using pure thyroid-sensitized T lymphoblasts. This is the first report showing the role of T lymphocytes in the induction of experimental autoimmune thyroiditis.

Animals↗
PubMed2000

Overlapping expression of amphioxus homologs of the thyroid transcription factor-1 gene and thyroid peroxidase gene in the endostyle: insight into evolution of the thyroid gland.

The endostyle is a pharyngeal organ of uro- chordates, cephalochordates, and primitive vertebrates. This organ has iodine-concentrating and iodine-metabolism activities, and therefore the endostyle is considered to be homologous to the follicle of the thyroid gland. In higher vertebrates the genes for both thyroid transcription factor-1 (TTF-1) and thyroid peroxidase (TPO) are expressed in the thyroid gland follicle. TTF-1 regulates the expression of TPO, which encodes an iodinating enzyme associated with thyroid hormone synthesis. A recent study showed that the ascidian TTF-1 and TPO genes are specifically expressed in the endostyle, but that the expression domains of these genes are not overlapping, suggesting that ascidian TPO is not regulated by TTF-1. To investigate the molecular mechanisms involved in the formation and function of the endostyle, with special reference to the evolution of the follicle of the thyroid gland, I isolated and characterized cDNA clones for the amphioxus homologs of the TTF-1 gene (BbTTF-1) and TPO gene (BbTPO) from Branchiostoma belcheri. Reverse transcriptase-polymerase chain reaction/Southern blotting revealed that both amphioxus TTF-1 and TPO genes are expressed mainly in the adult endostyle. Spatial and temporal expression patterns assessed by in situ hybridization revealed that BbTTF-1 is expressed in the endodermal cells during early embryogenesis and is maintained in all zones of the adult endostyle. On the other hand, expression of BbTPO is chiefly in zones 5 and 6 of the adult endostyle where it overlaps with that of BbTTF-1, and to a lesser extent in zones 1 and 3. This restriction of the expression of BbTTF-1 and BbTPO to the endostyle strongly suggests that the endostyle is homologous to the follicle of the thyroid gland. Moreover, the spatial and temporal expression patterns of these genes suggest that TTF-1 regulates TPO expression. The coexpression of these genes in amphioxus suggests that regulation of TPO by TTF-1 was present in the common ancestor of cephalochordates (acraniates) and craniates.

Amino Acid Sequence↗
PubMed1999

In vivo expression of thyroid transcription factor-1 RNA and its relation to thyroid function and follicular heterogeneity: identification of follicular thyroglobulin as a feedback suppressor of thyroid transcription factor-1 RNA levels and thyroglobulin synthesis.

We used in situ hybridization to evaluate thyroid transcription factor-1 (TTF-1) RNA expression in individual follicles and related this to thyroglobulin (Tg) synthesis in vivo, as estimated by immunohistochemical analysis. We studied the thyroids of Wistar rats treated with thyroxine (T4) or propylthiouracil (PTU), each of which modulates TSH levels, but affects follicular function and Tg accumulation in the follicular lumen very differently. We show that TTF-1 RNA levels in vivo correlate directly with an increase in the cytoplasmic accumulation of Tg within the cells of individual follicles. Because TTF-1 increases Tg gene expression, RNA levels, and protein synthesis in thyroid cell cultures and because there is no correlation with TSH-increased Tg degradation within the follicular lumen, the increased cytoplasmic accumulation of Tg in vivo is interpreted to reflect TTF-1-increased Tg synthesis. Increases in serum TSH levels in the PTU or T4 treated animals did not always correlate with increases in this measure of increased Tg synthesis; and TSH levels did not always correlate with changes in TTF-1 RNA levels that would be expected to accompany increased Tg synthesis. As one possibility, this suggested there might be a hitherto unrecognized suppressor of TTF-1 RNA levels and TSH-induced Tg synthesis in individual follicles. The immunohistochemical data suggested that this suppressor might be follicular Tg itself. Supporting this possibility, we show that physiological concentrations of highly purified 19S follicular Tg decrease TTF-1 RNA levels in rat FRTL-5 thyroid cells and inhibit the action of TSH to increase Tg synthesis. We therefore suggest that follicular Tg is a feedback autoregulator of thyroid function that can counterregulate TSH actions on thyroid function in vivo and in thyroid cells in culture. We suggest this phenomenon contributes to follicular heterogeneity in vivo.

Animals↗
PubMed1977

Thyrotropin binding and long acting thyroid stimulator absorbing activities in subcellular fractions from isolated thyroid cells and thyroid homogenates.

The ability of various thyroid subcellular fractions to bind [125I]iodo TSH and to absorb long-acting thyroid stimulator (LATS) and thyroid stimulating immunoglobulins (TSI) activities was examined. Membranes purified from thyroid homogenates or isolated thyroid cells absorbed LATS/TSI activities and specifically bound [125I]iodo TSH. Purified thyroglobulin, nuclei, mitochondria and ribosomes did not bind [125I]iodo TSH nor did they absorb LATS/TSI activities. Cell sap obtained by gentle lysis of isolated thyroid cells failed to absorb LATS/TSI activities and to bind labeled hormone. However, freeze-thawing of the cells fragmented the membranes, releasing [125I]iodo TSH binding as well as LATS/TSI absorbing activities into the soluble (cell sap) fraction. The results suggest that the LATS/TSI antigen is of cell surface origin, includes the TSH receptor or larger membrane fragments containing the receptor, and that its release into the soluble fraction is due to the fragmentation of the thyroid membrane during homogenization and preparative procedures.

Animals↗
PubMed2006

Thyroid-stimulating hormone receptor messenger ribonucleic acid measurement in blood as a marker for circulating thyroid cancer cells and its role in the preoperative diagnosis of thyroid cancer.

CONTEXT: Thyroid cancer cells express TSH receptor (TSHR) mRNA, and its measurement in the circulation may be useful in the diagnosis/management of differentiated thyroid cancer (DTC). OBJECTIVE: Our objective was to assess the diagnostic value of circulating TSHR mRNA for preoperative detection of DTC in patients with thyroid nodules. PATIENTS: We measured TSHR mRNA levels by RT-PCR in 258 subjects: 51 healthy subjects and 207 patients (thyroid nodules, n = 180; recurrent thyroid cancer, n = 27) with fine-needle aspirations (FNA) and/or thyroid/neck surgery. Eighty-nine patients also had d-1 postoperative levels assessed. OUTCOME MEASURES: TSHR mRNA levels were compared with FNA cytology for cancer detection preoperatively and serum thyroglobulin and/or whole-body 131I scans postoperatively. RESULTS: Based on cytology/pathology, 88 patients had DTC and 119 had benign thyroid disease. The TSHR mRNA levels in cancer patients were significantly higher than in benign disease (P < 0.0001). At a cutoff value of 1.02 ng/microg total RNA, the TSHR mRNA correctly classified 78.7% of patients preoperatively (sensitivity = 72.0%; specificity = 82.5%). Of 131 patients with FNA and surgery, 51 were FNA positive (all cancer), 17 were FNA negative (15 benign, two cancer), and 63 were indeterminate. TSHR mRNA correctly diagnosed DTC in 16 of 24 (67%) and benign disease in 29 of 39 (74%) patients with indeterminate FNA (combined sensitivity = 90%; specificity = 80%). Combining TSHR mRNA and ultrasound features for follicular lesions correctly classified all follicular cancers and could have spared surgery in 31% of these patients with benign disease. TSHR mRNA has a short life in circulation, and normalized levels on postoperative d 1 correlated with disease-free status, whereas elevated levels predicted residual/metastatic disease. CONCLUSIONS: TSHR mRNA measured with FNA enhances the preoperative detection of cancer in patients with thyroid nodules, reducing unnecessary surgeries, and immediate postoperative levels can predict residual/metastatic disease.

Adenocarcinoma, Follicular↗
PubMed1991

Anti-thyroid peroxidase antibodies in thyroid disorders and non-thyroid autoimmune diseases.

A new commercial method for measurement of anti-thyroid peroxidase (anti-TPO DYNOtest, Henning, Berlin) was evaluated in normal subjects and in patients with autoimmune thyroid and non-thyroid diseases, and compared to an immune fluorescence method for measurement of anti-microsomal antibodies (MicAb), and a radioimmunological method for quantifying thyroglobulin antibodies (TgAb). The majority of normal subjects had anti-TPO levels below 52 U/ml and patients with Hashimoto's thyroiditis had levels above 200 U/ml, with a good correlation to MicAb. In other autoimmune thyroid diseases the correlation was less pronounced. In non-thyroid autoimmune diseases MicAb showed falsely positive reactions in the presence of other autoantibodies, e.g. mitochondrial antibodies. The present study indicates that the anti-TPO method should probably replace measurements of MicAb for routine clinical use, thus providing a sensitive, precise, antigen specific method with the ability to reveal quantitative fluctuations. The study also indicates that TgAb could be abolished in routine diagnosis of autoimmune thyroid diseases and be reserved for special clinical situations, research purposes as well as measurement in sera before evaluation of serum thyroglobulin levels.

Adolescent↗
PubMed1997

Iodine metabolism and thyroid-related functions in organisms lacking thyroid follicles: are thyroid hormones also vitamins?

Thyroid-related functions in organisms devoid of follicular thyroid tissue have been reviewed. In the lamprey, a primitive vertebrate, the larva concentrates iodide and synthesizes thyroid hormones (TH) by iodoperoxidase (IP)-mediated iodination of a thyroglobulin (TG)-like molecule in a subpharyngeal afollicular endostyle. The endostyle is the thyroid homolog, and it reorganizes into a follicular thyroid at metamorphosis to the adult. Ascidians and amphloxus, invertebrate protochordate relatives of vertebrates, also concentrate iodide and synthesize TH in a subpharyngeal afollicular endostyle, but the endostyle never transforms to follicles. Ascidian plasma contains L-thyroxine and its more biologically active derivative 3,5,3'-triiodo-L-thyronine, and TH receptors exist, but TH effects are poorly understood. No other invertebrates possess an endostyle. Several invertebrates concentrate iodide at other sites and form protein-incorporated iodohistidines and iodotyrosines; however, de novo iodothyronine biosynthesis through IP-mediated TG iodination has not been established. Nevertheless, TH occur in invertebrates, and exogenous iodothyrosines or iodothyronines have effects on jellyfish, insects, and sea urchins. Furthermore, gut bacteria metabolize TH, and plants may synthesize TH by nonenzymatic oxidative iodination. Thus, TH occur in many organisms and, after ingestion and enteric absorption, can enter the food chain. Indeed, sea urchin larvae obtain TH required to induce metamorphosis from plant diatoms. Thyroid hormones can therefore have vitamin-like effects and, in conjunction with vitamin D, and possibly with other steroids, may be more aptly termed vitamones. Availability of exogenous TH has implications for models of invertebrate and vertebrate TH metabolism and iodine salvaging, and it may explain the prominent and probable ancestral role of peripheral mechanisms in regulating thyroidal status.

Animals↗
PubMed2002

Right thyroid hemiagenesis associated with papillary thyroid cancer and an ectopic prelaryngeal thyroid: a case report.

Failure of embryologic development of a lobe of the thyroid gland is a rare anomaly. We report a 47-year-old female with right thyroid hemiagenesis, papillary thyroid cancer, and an ectopic prelaryngeal thyroid rest. The preoperative diagnosis was made as a result of evaluating a progressively enlarging left thyroid mass by means of ultrasonography, technetium-99m thyroid scintigraphy, and fine-needle aspiration cytology. During the operation, an isthmus and an enlarged left lobe with a cancer mass 2 cm in diameter were found, and a solitary piece of thyroid tissue about 0.7 cm in length was present just below the hyoid bone. We conclude that recognition of this rare anomaly by means of both scintigraphy and ultrasonography is valuable for a complete thyroidectomy, and for avoiding unnecessary contralateral dissection and damage.

Carcinoma, Papillary↗
PubMed1975

Subacute thyroiditis in a lateral thyroid gland: evaluation of the pituitary-thyroid axis during the acute destructive and the recovery phases.

Subacute thyroiditis in a lateral, ectopic thyroid has been previously unreported. A 4 10/12-YEAR-OLD GIRL HAD AN ENLARGING MASS IN THE LEFT UPPER ANTERIOR NECK. Initially, the serum concentration of T4 was normal, T3 was elevated, and TSH was undetectable without response to TRH. RAI uptake was 1%. The data were consistent with subacute thyroiditis. Twelve weeks later the serum concentration of T4 was low and TSH was elevated; thyroid replacement therapy was given for 20 weeks. When this was discontinued, there was an initial increase and then a decrease in the TSH values accompanied by an increase in serum concentrations of T3 and T4 to normal during eight weeks. One must consider a lateral ectopic thyroid gland in the differential diagnosis of masses in the neck. Physicians must be aware that temporary hypothyroidism occurs during the course of subacute thyroiditis.

Acute Disease↗
PubMed1996

Treatment guidelines for patients with thyroid nodules and well-differentiated thyroid cancer. American Thyroid Association.

A set of minimum clinical guidelines for use by primary care physicians in the evaluation and management of patients with thyroid nodules or thyroid cancer was developed by consensus by an 11-member Standards of Care Committee (the authors of the article) of the American Thyroid Association, New York, NY. The participants were selected by the committee chairman and by the president of the American Thyroid Association based on their clinical experience. The committee members represented different geographic areas within the United States, to reflect different practice patterns. The guidelines were developed based on the expert opinion of the committee participants, as well as on previously published information. Each committee participant was initially assigned to write a section of the document and to submit it to the committee chairman, who revised and assembled the sections into a complete draft document, which was then circulated among all committee members for further revision. Several of the committee members further revised and refined the document, which was then submitted to the entire membership of the American Thyroid Association for written comments and suggestions, many of which were incorporated into a final draft document, which was reviewed and approved by the Executive Council of the American Thyroid Association.

Adenocarcinoma, Follicular↗
PubMedDate not supplied

Correlation of computerized gray-scale sonographic findings with thyroid function and thyroid autoimmune activity in patients with Hashimoto's thyroiditis.

PURPOSE: The objective of this study was to retrospectively assess whether computerized gray-scale sonography can allow objective measurement of thyroid echogenicity in patients with Hashimoto's thyroiditis (HT) at various functional stages of the disease. METHODS: Of the 77 patients with HT who were included in our study, 28 had been euthyroid, 20 had had subclinical hypothyroidism, and 29 had had clinical hypothyroidism. Of those with clinical hypothyroidism, 6 had been untreated and 23 had been receiving L-thyroxine substitution therapy. Fifty volunteers without thyroid disease served as a control group. Thyroid echogenicity was evaluated by computerized gray-scale sonography as mean tissue density (MTD) +/- standard deviation; the echogenicity of the prethyroid muscles served as a control of the system variability. RESULTS: The MTD was significantly lower for the patients with HT (15.9 +/- 4) than for the control subjects (24.3 +/- 3; p < 0.05). Moreover, a significant difference was found between the MTD values of euthyroid patients with HT (18.9 +/- 3.4) and hypothyroid patients with HT analyzed either as a group (14.3 +/- 3.8) or separately for subclinical hypothyroidism (14.9 +/- 3.8) and clinical hypothyroidism (13.9 +/- 3.7; p < 0.05). The lowest MTD was found in patients with untreated clinical hypothyroidism (11.1 +/- 4.3), with a significant difference (p < 0.05) compared to all other groups of patients. Untreated patients with clinical hypothyroidism also showed the highest mean anti-thyroid peroxidase autoantibody levels (1,286 +/- 177 IU/ml versus 570 +/- 489 IU/ml for L-thyroxine-treated patients; p < 0.05), although no correlation between the MTD values and anti-thyroid peroxidase autoantibody levels was found in any group of patients. CONCLUSIONS: Computerized gray-scale sonography provides an objective measure of thyroid hypoechogenicity, which correlates well to the clinical stages of HT. Use of this modality may prove beneficial in the diagnosis and follow-up of patients with HT.

Adolescent↗
PubMed1991

Expression of intercellular adhesion molecule-1 (ICAM-1) on thyroid epithelial cells in Hashimoto's thyroiditis but not in Graves' disease or papillary thyroid cancer.

In order to study the possible role of antigen-independent adhesion systems in thyroid autoimmunity, we evaluated by indirect immunofluorescence the expression of lymphocyte functional antigen-1 (LFA-1) and its ligand ICAM-1 on mononuclear cell infiltrates (when present) and thyroid follicular cells of four patients with Hashimoto's thyroiditis, 30 with Graves' disease, five with papillary cancer, two with follicular adenoma, and two normal thyroid specimens. The expression of MHC class I and class II antigens was also evaluated. Most mononuclear infiltrates were LFA-1 positive, as expected. A positivity for ICAM-1 on follicular cells was observed in three out of four Hashimoto's thyroiditis specimens; such a phenomenon was totally absent in Graves' disease or any other pathological condition, or in normal tissue. MHC class II expression on thyrocytes was observed in all the patients with Hashimoto's thyroiditis, in 27 out of 30 with Graves' disease and in three out of five papillary cancer specimens.

Adult↗
PubMed1991

Autoimmune thyroiditis with transient thyrotoxicosis: comparison between painful thyroiditis and painless thyroiditis.

Clinical and laboratory findings and long-term outcomes in 8 patients (7 women) with autoimmune thyroiditis (AT), aged 34-59 years, who had a painful tender goiter and a transient thyrotoxicosis with a low thyroid radioactive iodine uptake (RAIU), were compared with those in 15 patients (13 women) with painless thyroiditis (PT), aged 23-69 years. Six painful AT and 6 PT patients had a history of prior awareness of goiter. All patients with painful AT had a moderate or marked elevation of erythrocyte sedimentation rate and a positive result for C-reactive protein, while only 3 PT patients (group B) did. There were no significant differences between the mean age, duration of symptoms, white blood cell count, serum triiodothyronine (T3) and thyroxine (T4) concentrations, serum T3/T4 ratio and duration of thyrotoxicosis after the initial examination and prevalences of positive results for antithyroglobulin and -microsomal antibodies in the two diseases. Two of 8 painful AT patients showed a histologically chronic fibrous variant and 6 others showed chronic lymphocytic thyroiditis. All PT patients examined also showed lymphocytic thyroiditis. Two and 5 painful AT patients developed transient and persistent hypothyroidism, respectively, while 8 [7 in group A (normal ESR), 1 in group B] and 3 PT patients (1 in group A, 2 in group B) did, respectively. The mean serum thyroid-stimulating hormone level in the hypothyroid phase in painful AT patients was higher than that in PT patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Simultaneous expression of thyroid peroxidase and human leukocyte antigen-DR by human thyroid cells: modulation by thyrotropin, thyroid-stimulating antibody, and interferon-gamma.

Major histocompatibility class II molecules human leukocyte antigen-DR (HLA-DR) are abnormally expressed by human thyroid cells (HTC) in autoimmune thyroid glands. The simultaneous expression of HLA-DR and organ-specific autoantigens such as thyroid peroxidase (TPO) by HTC might enable these cells to function as antigen-presenting cells, thus perpetuating the autoimmune process. The aim of the present study was to clarify the interplay of endocrine (TSH) and immune [TSab or interferon-gamma (IFN gamma)] factors on the expression of HLA-DR and TPO in HTC. Thyrocytes were cultured with supernatants of T-cells cloned from the infiltrate of Hashimoto's glands, human recombinant IFN gamma, TSab, or TSH. These factors were added either alone or in different combinations and sequences. HLA-DR and TPO were identified in HTC by a double indirect immunofluorescence technique, using a monoclonal anti-HLA-DR antibody and human serum containing anti-TPO antibody, respectively. IFN gamma, either recombinant or produced by T-cell clones, induced HLA-DR appearance in thyrocytes, whereas TSH or TSab stimulated TPO expression. The appearance of HLA-DR induced by IFN gamma was accompanied by a progressive reduction of TPO despite stimulation by TSH or TSab. This decline reached a nadir after 9-10 days in different primary cultures. During this period, a percentage of cells ranging from 10-40% simultaneously expressed HLA-DR and TPO on their surface and in the cytoplasm. The inhibition of TPO expression and the appearance of HLA-DR induced by IFN gamma were rapidly reverted when TSH or TSab was substituted for interleukin in the culture medium and vice versa. We conclude that 1) the expression of TPO or HLA-DR in thyroid cells is a dynamic phenomenon that is differently influenced by TSH, TSab, and IFN gamma. It is the interplay of these factors in different follicles and during different periods of time that determines the expression of TPO alone, HLA-DR alone, or both molecules together in the same thyroid cell; 2) during exposure to TSH (or TSab) and IFN gamma, TPO and HLA-DR can be expressed simultaneously by thyroid cells for up to 7 days; and 3) the modulation of HLA-DR and TPO by supernatants of T-cells cloned from Hashimoto's glands is reproduced by IFN gamma alone.

Antibodies, Monoclonal↗
PubMed1985

Thyroid abnormalities in dermatitis herpetiformis. Prevalence of clinical thyroid disease and thyroid autoantibodies.

We studied thyroid abnormalities in 50 patients with dermatitis herpetiformis. Two patients had a history of hyperthyroidism, and 5 had hypothyroidism and were on thyroid replacement therapy. Three patients had had thyroidectomies for nodules, and 5 had asymptomatic goiter. Two patients were clinically euthyroid with elevated thyrotrophin and low normal thyroxine levels, indicating early thyroid insufficiency. Thyroid microsomal antibodies were seen in 38% of patients with dermatitis herpetiformis compared to 12% of controls. The presence of clinical or serologic thyroid abnormalities in 26 of 50 patients shows a significant but unexplained association between dermatitis herpetiformis and thyroid disease.

Adolescent↗
PubMed1996

Interphase ribosomal RNA cistron staining in thyroid epithelial cells in Grave's disease, Hashimoto's thyroiditis and benign and malignant tumours of the thyroid gland.

Aim-To evaluate the expression of ribosomal cistrons in human thyroid epithelial cells (TECs) of patients with Grave's disease, Hashimoto's thyroiditis and benign and malignant tumours of the thyroid gland.Methods-TEC nucleoli were investigated in fine needle biopsy specimens from 10 controls, 39 patients with Grave's disease, 15 with Hashimoto's thyroiditis, 56 with benign, and 15 with malignant tumours of the thyroid. A one step silver staining method was applied. In most cases serum concentrations of thyroxine and triiodothyronine as well as goitre size were determined. In every case 100 TECs were evaluated for the mean numbers of nucleoli and for the average number of argyrophilic nucleolar organiser regions (AgNORs) per nucleus.Results-NORs were activated in all patients, but not in controls. The numbers of AgNORs in patients with Grave's disease were closely correlated with thyroxine or triiodothyronine, or both, concentrations and with the size of the thyroid. In patients with Hashimoto's thyroiditis about 30% of TECs nucleoli did not contain AgNORs, whereas others were heavily impregnated with silver. Compared with controls and benign tumours, the nucleoli of carcinomatous TECs were larger and irregular in shape. The mean number of AgNORs per nucleus in malignant cells was higher than that in their benign counterparts.Conclusions-The mechanism by which NORs are activated in TECs varies depending on the type of lesion. The higher AgNOR score in TECs from malignant tumours can be used to distinguish them from their benign counterparts.

Journal Article↗