Color Doppler sonography patterns related to histological findings in Graves' disease.

The aim of this work was to correlate color duplex sonography (CDS) patterns and thyroid histology in hyperthyroid Graves' disease (GD) patients. Sixteen patients with relapsed GD were studied. Before starting a new cycle of medical therapy with methimazole in decreasing doses for 3 to 6 months (baseline study), the patients underwent functional, autoimmune, and CDS studies. The same studies were carried out again just before surgery (presurgical study) after medical therapy had produced a normalization of thyroid hormone serum levels. The thyroid glands were histologically examined and their patterns were compared with CDS patterns. Thirty-three normal subjects were used as a control group. At baseline, 6 patients (group I) had intraparenchymal homogeneous vascular color spots or diffusely distributed over the parenchyma lobe or in areas alternating with avascular zones (CDS-A pattern). In 8 patients (group II) the thyroid had vascular bands with avascular or poorly vascularized parenchymal areas (CDS-B pattern). In 2 patients, the 2 patterns were present in the same thyroid (A-B pattern or mixed pattern). In these 2 patients the histological aspects were more similar to the CDS-B pattern than the CDS-A pattern. The 2 groups of patients differed in the velocity of systolic peak (VP) that was significantly higher in group I than in group II. In the presurgical study, no changes relative to CDS patterns were observed in patient groups I and II. The VP did not show any appreciable modifications in either group of patients. The thyrotropin-stimulating antibodies (TRAb) returned to normal levels in group II, but not in group I. The 2 CDS patterns, observed in the baseline study, were histologically characterized either by a richly vascularized parenchyma with prevalent endothelial hyperplasia (parenchymatous goiter, CDS-A) or by fibrotic septation with prevalent vascular intimal hyperplasia (CDS-B). In conclusion, this CDS study in GD patients showed 2 distinct vascular patterns. The thyroid glands were histologically characterized by either a richly capillary vascularized parenchyma (parenchymatous goiter, CDS-A aspect) or by fibrotic septation with prevalent intraseptal arteriolar-like hyperplasia (fibrous goiter, CDS-B aspect). Such differences may be secondary to a different duration of hyperthyroidism and/or intensity of TRAb thyroid stimulation.

TGF-beta 1 immunohistochemistry in goiter: comparison of patients with recurrence or no recurrence.

The aim of this work was to establish whether the immunohistochemical pattern for TGF-beta 1 in goiters that recur after thyroid surgery is different when compared with goiters that do not recur postoperatively. Twelve goiters, surgically removed by partial resection between 1977 and 1982, were studied. Ten years after surgery, 6 patients had recurrence of goiter or thyroid nodules (group 1); the others did not have any recurrence (group 2). The presence and location of TGF-beta 1 were evaluated a posteriori by immunohistochemistry in histological samples of the tissue that was removed. In each goiter specimen, 50 randomly selected subcapsular follicles were studied to evaluate the percentage of follicles negative or positive for TGF-beta 1 and the protein's intrathyrocyte location. In the slides of group 1, the percentage of TGF-beta 1-positive follicles was statistically (p < 0.01) greater (93.1%) than in group 2 (71.4%). No difference in the location of TGF-beta 1 was found. The authors found a greater percentage of positive follicles for the TGF-beta 1 protein in group 1 patients. In conclusion, TGF-beta 1 production in goiter is variable, time dependent, and may be a marker of active cellular proliferation due to chronic exposure to a goitrogen stimulus. Thus, the more TGF-beta 1 found, the more the cell is stimulated and, therefore, the greater the risk of relapse.

TGF beta 1 immunostaining patterns and locations in adenoma which later recurred.

To investigate whether the immunohistochemical pattern of TGF beta 1 may be a marker of relapse for adenomatous pathology, 18 follicular adenomas, surgically removed by hemithyroidectomy between 1977 and 1982, were studied. The adenomas were divided into two groups according to the presence (group 1, N = 9) or absence (group 2, N = 9) of nodules recurring in the residual thyroid tissue. The presence and location of TGF beta 1 were evaluated a posteriori by immunohistochemistry in the removed adenoma. Fifty randomly selected subcapsular follicles were studied in each adenoma in order to evaluate the percentage of positive follicles and TGF beta 1 intra-thyrocyte location. In adenoma of group 1, the percentage of positive follicles for TGF beta 1 was lower (80%) than in adenoma of group 2 (84%); this was, however, not statistically significant. The location of TGF beta 1 was mainly at the cell base of the epithelial cells in the microfollicles of group 1, but was dominant at the cell apex in group 2 (p < 0.01). In conclusion, adenoma recurrence is independent of TGF beta 1 production; it may be due to an abnormal TGF beta 1 regulation in response to hyperplasiogenic stimuli.

[Evaluation of the role of repeat needle biopsy in the diagnosis and follow-up of thyroid nodules]. / Valutazione del ruolo della ripetizione dell'agoaspirato nella diagnosi e follow-up del nodulo tiroideo.

The goal of the present study was to determine in what percentage of cases was an initial benign cytological diagnosis modified to malignant or suspicion of malignancy by a second aspiration biopsy. The study group consisted of 708 patients, 98 males and 610 females, mean age 46.3 +/- 13.7; FNB was always repeated on the same nodule. The first FNB (cytology I), classified the nodule as: non-diagnostic (group I, 205 cases) or diagnostic (group II, 503 cases); these latter were classified as benign (471) or suspect (32). In 82 cases of group I the second examination after six months (cytology II) was still unable to arrive at a diagnosis; in the remaining 123 cases, it was able to classify 120 as benign and 3 as suspect (the latter being followed up by diagnostic surgery). In group II, cytology II modified the initial diagnosis from benign to suspect (8 cases) or non-diagnostic (7 cases). On the other hand, 29 cases had a change of their initial diagnosis from suspect to benign. The remaining cases of group II repeated a thyroid FNB after one year (cytology III) with a result of benign (486) or non-diagnostic (6). In the 14 cases followed up by diagnostic surgery, due to a second biopsy diagnosis of suspicion, histology showed the presence of Follicular Adenoma in 12 cases and Hashimoto's Thyroiditis in the remaining 2. Based on follow-up surgery, the suspicious lesions seen on the second biopsy turned out to be all non-malignant. However, it is important to underline the greater number of cases where the second examination gave a benign diagnosis when the first examination was judged suspicious. One can conclude that it may be useful to repeat FNB: 1) when the first exam resulted in an inadequate sample, as a second biopsy allows one to classify the nodule 60% of the time; 2) in all cases where there is an initial benign diagnosis, when non-surgical follow-up (clinical and/or echographic) is suspicious.

Enhanced expression of transforming growth factor beta1 in rat thyroid hyperplasia is thyrotropin induced and time dependent.

Forty-three 8-week-old male Wistar rats were studied to evaluate temporal changes of transforming growth factor beta1, (TGF-beta1) mRNA levels in thyroid tissue during pharmacologically induced goiter. Four rats were treated with purified bovine thyrotropin (TSH; Ambinon, 2 mU/day sc) for 7 days before being sacrificed. Thirty-one were treated with propylthiouracil (PTU), added to their drinking water at a concentration of 0.2 g%, and subsequently were sacrificed as follows: five after 1 week (PTU-1): five after 2 weeks (PTU-2); five after 4 weeks (PTU-4); five after 8 weeks (PTU-8); five after 12 weeks (PTU-12). In six rats, after 12 weeks of treatment. PTU was withdrawn for 2 months and subsequently started again in three rats which were sacrificed after 2 weeks (PTU-R); the remaining three rats were sacrificed without any further treatment (PTU-R control). Eight rats (control rats) were never treated and served as controls. After sacrifice, blood was drawn for determination of total thyroxine and the thyroid was excised and subdivided into two lobes. Northern analysis for TGF-beta1 was performed in one lobe. while histological and immunohistochemical studies were performed in the other lobe. Gene expression of TGF-beta1 was induced in TSH- and PTU-treated rats. In TSH-treated rats TGF-beta1 gene expression was less detectable than in PTU-treated rats, where it became evident after 2 weeks and remained through weeks 4-8. Gene expression of TGF-beta1 wits also seen in PTU-R rats, but not in the control and in the PTU-R control. Immunohistochemical analysis showed a different presence and location for the TGF-beta1 protein, which appears to be dependent on the time of exposure to mitogenic stimulus. In conclusion, TGF-beta1 is produced in response to both a direct (TSH by itself) and indirect (TSH induced by PTU-induced hypothyroidism) cellular proliferative stimulus and is not linked to an adaptative phenomenon secondary to hypothyroidism. The immunohistochemical location of TGF-beta1 within the thyrocytes is influenced by mitogen exposure time. A TGF-beta1 immunohistochemical evaluation may be important to define exposure time and activity of goitrogenic stimuli.

[Anti-microsomal, anti-thyroglobulin antibodies and thyroid stimulants in hyperthyroid subjects. Analysis of 315 patients followed-up for 3 years at a single medical center]. / Anticorpi anti micrsomi, anti tireoglobulina e tiroido stimolanti in soggetti ipertiroidei. Analisi di 315 pazienti seguiti per tre anni presso un unico centro medico.

The objective of the study was to evaluate the significance of the determination of antithyroid antibodies in hyperthyroid patients. Two-hundred-fifteen untreated Graves' hyperthyroid patients (active toxic diffuse goiter-TDG), 54 Plummer's hyperthyroid patients (focal hyperthyroidism) and 46 subjects with other forms of hyperthyroidism were studied. Serum levels of T4, T3, TSH, TSH receptor antibody (TRAb), microsomal antibody (TMAb), and thyroglobulin antibody (TGAb) were evaluated before starting treatment, at regular intervals during therapy, and during the follow-up period after therapy was withdrawn. The antibodies were positive in all patients with active and non-active TGD but positive in only two patients (3.7%) with focal hyperthyroidism. During the treatment interval, TRAb, TMAb and TGAb serum levels fell with a nadir in the 7th month of therapy. In particular, TRAb fell to normal levels in all patients who had basal levels less than 500 U/l (97.7% of the cases) while TMAb and TGAb remained positive. Relapses, following the completion of therapy, occurred in 20.4% after one year and in 33% after two years. Relapses were always linked to a new increase in TRAb. In conclusion, TRAb can be useful in the determination of early disease and in diagnosing remission. It did not appear useful as a prognostic indicator for relapse in individual patients.