Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0027627 (metastases)
103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thyroid hormone production by metastases of differentiated thyroid carcinoma is very rare and its pathogenesis is still unknown. The aim of this study was to present some clinical and demographic evidence that thyroid hormone-producing metastases of differentiated thyroid carcinoma are related to environmental factors, probably iodine deficiency. A cross-sectional study was performed on thirty-five patients with distant metastases, identified in a group of 125 patients with differentiated thyroid carcinoma previously submitted to total or near total thyroidectomy. In 6 patients (5 females, 1 male; age range, 50 to 64 yr) we had evidence that the metastases were actively producing thyroid hormones and in 29 patients (21 females, 8 males; age range 8 to 84 yr) the metastases were considered to be nonthyroid hormone-producing. Serum levels of T3, T4, and thyroglobulin were measured by RIA, TSH by IRMA, and 131I whole-body scintigraphy was performed 72 h after 187 Mbq of 131I. All patients with metastases producing thyroid hormones presented a pure follicular thyroid carcinoma. They also differed from patients with nonproducing metastases in the frequent presence of goiter of long duration as the first clinical manifestation of thyroid disease (p < 0.01), and a higher proportion of patients coming from an iodine deficient area (5/6 vs. 6/29, p < 0.05). In these patients the serum thyroglobulin levels tended to be higher (p = 0.069) as compared with the nonproducing metastases group. In conclusion, a late diagnosis of follicular carcinoma in patients with long-standing multinodular goiter allowed the development of well differentiated and bulky metastases retaining the ability to produce thyroid hormones.
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PMID:Thyroid hormone-producing metastases in differentiated thyroid cancer. 885 87

A rare case of hyperthyroidism in the presence of a functioning bone metastasis secondary to an occult thyroid cancer is reported. A 59-year-old woman's pelvic bone metastasis was much too extensive and hypervascular to permit resection. An I-131 scan showed striking activity in the pelvic metastasis, which reflected ectopic excessive production of thyroid hormone by a functioning metastatic thyroid carcinoma. After total thyroidectomy, the patient received I-131 ablation and transcutaneous intra-arterial embolization therapy but her metastasis progressively enlarged. Microscopically, concomitant follicular and papillary cancer was found in close proximity to the thyroid. The patient now has vertebral metastases, and her hyperthyroid state still requires methymazole to prevent thyrotoxicosis.
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PMID:Carcinoma of the thyroid manifested as hyperthyroidism caused by functional bone metastasis. 909 77

Outcome was compared in 1,004 patients with differentiated thyroid carcinoma (DTC) who underwent thyroid remnant ablation with 131I (n = 151) or were either treated with thyroid hormone alone (755) or given no postoperative medical therapy (98). Median follow-up time was 18.7 years for patients treated with thyroid hormone alone, 21.3 years for those given no adjunctive medical therapy, and 14.7 years for those treated with thyroid remnant ablation. End points measured were cancer recurrence, development of distant metastases, and death due to thyroid carcinoma. Tumor recurrence was about threefold lower (p < 0.001) and fewer patients developed distant metastases (p < 0.002) after thyroid remnant ablation than after other forms of postoperative treatment, an effect observed only in patients with primary tumors > or = 1.5 cm in diameter. The doses of 131I were stratified into two groups: 29-50 mCi (mean 47 mCi) in 43% and 51-200 mCi (111 mCi) in 57% of patients. Both groups experienced similar recurrence rates (7% and 9%, respectively, p = 0.7). There were fewer cancer deaths after thyroid remnant ablation than after the other treatment strategies (p < 0.001), differences that occurred only in patients aged 40 years or older at the time of initial treatment and with primary tumors > or = 1.5 cm. The variables that influenced cancer recurrence in a Cox proportional hazards model were absence of cervical lymph node metastases (hazards ratio [HR] 0.8), tumor stage (HR 1.8), and treatment of the thyroid remnant (HR 0.9); those that independently affected cancer-specific death rates were age (HR 13.3), recurrence of cancer (16.6), time to treatment (HR 3.5), thyroid remnant ablation (HR 0.5), and tumor stage (HR 2.3). This study suggests that thyroid remnant ablation is effective in reducing recurrence of DTC in patients of all ages and reduces the risk of death from thyroid carcinoma in patients > age 40 at the time of diagnosis. These effects are not apparent in patients with isolated tumors < 1.5 cm that are not metastatic to regional lymph nodes or invading the thyroid capsule. The optimal dose of 131I necessary to achieve this effect remains uncertain.
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PMID:Thyroid remnant 131I ablation for papillary and follicular thyroid carcinoma. 913 98

Physical and biologic principles, availability, and experience in use determine which radiopharmaceuticals will be the optimal agents to portray scintigraphically thyroid cancers. However, clinical reasoning must dictate which scanning procedure to use and when. To identify functioning thyroid nodules, and thereby exclude malignancy and also disclose the source of excess thyroid hormone, technetium Tc 99m pertechnetate is the agent of choice. To evaluate patients with metastatic differentiated thyroid cancer (DTC) for possible radiopharmaceutical therapy, low doses (no more than and probably less than 74 MBq or 2 mCi) of 131I iodide are preferred. 131I is especially necessary if dosimetry is undertaken to help prescribe the optimal therapeutic dose of 131I. For less well differentiated tumors that do not concentrate 131I, most experience has been with thallium 201, which enables depiction of most metastases, but, in time, newer agents may be found to produce superior scans. The goal of imaging of the less well differentiated cancers must be to direct additional therapy such as external beam radiation of surgical excision. It is unlikely that any scanning procedure that depends on the physiologic and biochemical activities of DTC will have as much sensitivity for locating tumors in the euthyroid as in the hypothyroid patient. A majority of medullary carcinomas of the thyroid (MCT) have been portrayed by indium 111 octreotide and by 99mTc pentavalent dimercaptosuccinic acid; other agents have concentrated to lesser levels in the tumors or have not been investigated as extensively. As of now, metastatic MCT defies therapy, and, therefore, scanning to detect the tumors has little clinical utility.
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PMID:Selection of the optimal scanning agent for thyroid cancer. 913 4

This article discusses several aspects of the evaluation and management of differentiated thyroid carcinoma that are changing or may change in the near future. Although conventional treatment of this disease is highly effective, some modification may improve the welfare of patients and the overall results. Because the symptoms of hypothyroidism are vexing, there has been great interest in using recombinant human thyroid-stimulating hormone (rhTSH) to prepare patients for iodine 131 imaging. rhTSH has been about as effective as thyroid hormone withdrawal for diagnostic imaging so that approval for this use is expected. Another topic of interest is the administration of 131I therapy to patients whose serum thyroglobulin levels are abnormal but whose diagnostic 131I scans are negative. Because the 131I scans after therapy are often abnormal in these patients and a reduction of serum thyroglobulin can occur, this approach seems effective. The long-term impact of this therapy on recurrence and survival, however, is unknown. A third issue that is currently under review is the amount of 131I that should be used for diagnostic scanning. Although past opinion favored larger doses, "stunning" of thyroid remnant and tumor can occur with diagnostic 131I imaging. Substituting iodine 123 is an alternative for postthyroidectomy scanning, but when administered as 300 uCi it is less accurate than 131I for recurrent disease or distant metastases. Related to these issues, two other topics are reviewed: the use of other radiopharmaceuticals for imaging patients with thyroid cancer, and 131I dosimetry.
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PMID:The changing role of radioiodine in the management of differentiated thyroid cancer. 914 57

Recombinant human TSH (rhTSH) is known to stimulate 131I uptake and thyroglobulin (Tg) release from the postoperative remnant and metastases in thyroid cancer patients, but its effects on serum thyroid hormone and Tg concentrations in normal subjects have not been reported. Before using rhTSH in the management of thyroid disorders other than cancer, the thyroid response to rhTSH in normal subjects must be assessed. Six subjects, two men and four women, without evidence of thyroid disease, including normal serum free T4 index and TSH concentrations and negative tests for antithyroid peroxidase and Tg, were studied. Each received 0.1 mg rhTSH, im, 11% of the lowest dose that has been administered to thyroid cancer patients. Blood was obtained before; 2, 4, and 8 h after; and 1, 2, 3, 4, 7, and about 3 weeks after rhTSH administration. Serum TSH significantly increased at 2 h (mean +/- SE, 2.4 +/- 0.9 to 40.7 +/- 7.4 mU/mL), peaked at 4 h (50.9 +/- 9.3), remained significantly elevated for 1 day, and was significantly below baseline (0.8 +/- 0.5) 7 days after rhTSH administration. Serum T3 increased significantly at 4 h (115 +/- 4 to 190 +/- 14 ng/dL), peaked at 24 h (217 +/- 23 ng/dL), and remained significantly elevated for 3 days (151 +/- 12 ng/dL). Serum T4 increased significantly at 8 h (7.3 +/- 0.2 to 9.8 +/- 0.4 micrograms/dL), peaked at 24 h (11.2 +/- 0.5 micrograms/dL), and remained significantly elevated for 4 days (9.4 +/- 0.5 micrograms/dL). Serum Tg did not change for the first 8 h, increased significantly at 1 day (15.9 +/- 3.9 to 34.7 +/- 6.0 ng/mL), peaked at 2 days (44.2 +/- 7.0 ng/mL), and remained significantly elevated for 4 days (37.7 +/- 13.7 ng/mL). All values returned to baseline at 3 weeks. TSH antibodies were not detected at 3 weeks. A single dose of 0.1 mg rhTSH is a potent stimulator of thyroid function in normal subjects. rhTSH may be a useful agent to test thyroid reserve and for use in clinical settings that require direct thyroid stimulation.
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PMID:Recombinant human thyrotropin is a potent stimulator of thyroid function in normal subjects. 928 6

Surgical, thyroid hormone and radioactive 131I therapy are the standard curative treatments for well differentiated thyroid cancer. However, for residual, recurrent and nodal involvement of well differentiated thyroid cancer, external radiotherapy may be important in preventing distant metastases. The postoperative treatment of well differentiated human thyroid cancer with external radiotherapy is controversial. We retrospectively reviewed the records of 699 patients with papillary or follicular thyroid cancer, of whom 72 received external radiotherapy treatment after surgery. Thirty-two of these patients were at clinical stage 2 or 3 at the time of diagnosis while 172 patients at clinical stages 2 or 3 did not receive external radiotherapy after surgery. The patients who received external radiotherapy were older than those who did not (42.9 +/- 14.5 vs. 38.6 +/- 15.3), although this was not statistically significant. There were no significant differences in clinical parameters including surgical methods employed, histopathological types of cancer, follow-up stages, postoperative thyroglobulin levels, tumor size, accumulated 131I doses and survival rates between the two groups. To clarify the effect of external radiotherapy in patients with local invasion, we compared the survival rates of the patients with clinical stage 3 in the two groups and again no significant difference was found. During the follow-up period, 21 (28.4%) of the 72 patients who received external radiotherapy died of thyroid carcinoma. In our limited period of study, external radiotherapy did not improve the survival rate of patients with well differentiated thyroid cancer, though it appeared to cause temporary tumor regression.
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PMID:Results of external beam radiotherapy in patients with well differentiated thyroid carcinoma. 937 12

It is very important to diagnose correctly the etiology of thyrotoxicosis, because the course and treatment of thyrotoxicosis with low radioactive iodine uptake differ significantly from that of hyperthyroidism due to Graves' disease or toxic nodular goiter. Many causes of subacute thyroiditis have been identified producing a characteristic course of transient hyperthyroidism, followed by hypothyroidism, and usually recovery. Ectopic hyperthyroidism includes factitious thyroid hormone ingestion, struma ovarii, and, rarely, large deposits of functioning thyroid cancer metastases. Iodine-induced hyperthyroidism may be associated with low radioiodine uptakes. Amiodarone-associated hyperthyroidism may be the result of subacute thyroiditis or iodine-induced hyperthyroidism; assessment and treatment can be quite challenging.
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PMID:Syndromes of thyrotoxicosis with low radioactive iodine uptake. 953 35

We report two cases of thyrotoxicosis resulting from hyperfunctioning lung metastases from differentiated thyroid cancer. In both patients, a simultaneous diagnosis of thyrotoxicosis and metastatic thyroid cancer was made, based on thyroid function tests as well as 131I whole-body scans showing low thyroid uptake of radioiodine and multiple foci of intense 131I uptake in the lungs. After total thyroidectomy (performed in Patient 2 only) and 131I therapy (cumulative dose of 12.3 GBq in Patient 1 and 9.6 GBq in Patient 2), there was a rapid clinical improvement with significant reduction of the pulmonary metastatic disease in both patients: Patient 1 became euthyroid, while Patient 2 became hypothyroid. Analysis of the 54 cases reported in the literature, including the 2 cases described here, shows this to be a very rare cause of thyrotoxicosis and one that can pose serious problems for both the diagnostic evaluation and choice of therapeutic strategy when compared with the much more common nonhyperfunctioning metastases from thyroid cancer. Lesser degrees of thyroid hormone secretion by differentiated thyroid cancer may be detected and exploited diagnostically by the chromatographic analysis of serum for endogenously labeled thyroid hormones after 131I administration.
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PMID:Severe thyrotoxicosis due to functioning pulmonary metastases of well-differentiated thyroid cancer. 966 94

Serum thyroglobulin measurement by immunoassay is used to detect residual or recurrent thyroid cancer after thyroid ablation. However, the usefulness of immunoassay is limited by both the requirement for thyroid hormone withdrawal to attain optimal test sensitivity and interference by antithyroglobulin antibodies. To circumvent these problems, we amplified thyroglobulin messenger ribonucleic acid (mRNA) in peripheral blood using RT-PCR and compared the accuracy of this test to serum thyroglobulin immunoassay in patients with thyroid cancer. Thyroglobulin mRNA was amplified from peripheral blood of 77 patients who had undergone thyroidectomy for well differentiated thyroid cancer, 68 of whom while taking thyroid hormone for TSH suppression. Patient staging was based on the most recent radioiodine scan after thyroid hormone withdrawal. Ten normal control subjects were also studied. Among patients taking T4, thyroglobulin mRNA was detected in 26 of 33 patients with either thyroid bed or metastatic iodine-avid tissue on most recent withdrawal scan (79%), whereas serum thyroglobulin was detected in 12 of these 33 patients (36%; P < 0.001). Thyroglobulin mRNA was detected in 7 of 35 patients (20%) with negative radioiodine scans, 12 of 19 patients (63%) with radioiodine uptake in the thyroid bed, and all 14 patients with metastases, including 2 patients with antithyroglobulin antibodies. Thyroglobulin mRNA was detected in all 10 normal subjects. Epithelioid cells that stained strongly with antithyroglobulin antibodies were identified in blood. Detection of circulating thyroglobulin mRNA is a more sensitive marker of residual thyroid tissue or cancer than immunoassay for serum thyroglobulin, particularly in patients treated with thyroid hormone or who have circulating antithyroglobulin antibodies.
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PMID:Molecular diagnosis of residual and recurrent thyroid cancer by amplification of thyroglobulin messenger ribonucleic acid in peripheral blood. 985 49


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