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)

Cloning, functional characterisation, and diagnostic proof of the expression of sodium-iodide-symporter (NIS) in the thyroid are essential steps for a better understanding of function and regulation of thyroid hormone synthesis, which is limited by the availability of the trace element iodide. The physiological or pharmacological modulation of NIS function can now be used for a rational functional diagnosis and therapy of thyroid diseases. Diagnostic procedures based on analysis of the this gene or its expression are already in use for the analysis of benign and malignant alterations of the thyroid. Experimental protocols aiming at the functional expression of NIS in thyroid tumors or their metastases which lost capability for iodide uptake are currently developed. Furthermore, techniques are under investigation to express functional NIS by gene transfer in those benign or malignant tissues, tumors, metastases, which normally do not accumulate iodide. This would allow application of radioiodide therapy, a save and established technique to non-thyroid-related fatal diseases.
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PMID:[The sodium-iodide-symporter (NIS): function, regulation and clinical importance]. 1035 44

Radioiodine-131 imaging is the traditional method of detecting residual or recurrent differentiated thyroid cancer. The stimulation of such tissues to take up radioiodine may be achieved either by complete cessation of thyroid hormone, by partial thyroid hormone withdrawal, or by the administration of recombinant human thyrotropin (TSH). Complete or partial thyroid hormone withdrawal may result in serum TSH concentrations adequate for radioiodine imaging in up to 90% of patients. When known or suspected recurrent or metastatic disease is not evident on radioiodine imaging, single photon emission tomographic imaging with either thallium-201 chloride or technetium-99m-MIBI compounds may detect up to 80%-90% of cancers at least 1 to 1.5 cm in size, although specificity is less than with 131I. Fluorine-18-FDG positron emission tomography is a somewhat less available but acceptable substitute for thallium-201 or 99mTc-MIBI imaging. Tumor foci that concentrate either TI-201 or 18FDG intensely with little or no 131I uptake appear to behave more aggressively than those concentrating 131I avidly.
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PMID:Detection of residual and recurrent thyroid cancer by radionuclide imaging. 1036 74

Radioiodine may accumulate at sites of inflammation or infection. We have seen such accumulation in six thyroid cancer patients with a history of previously treated pulmonary tuberculosis. We also review the causes of false-positive radioiodine uptake in lung infection/inflammation. Eight foci of radioiodine uptake were seen on six iodine-123 diagnostic scans. In three foci, the uptake was focal and indistinguishable from thyroid cancer pulmonary metastases from thyroid cancer. In the remaining foci, the uptake appeared nonsegmental, linear or lobar, suggesting a false-positive finding. The uptake was unchanged, variable in appearance or non-persistent on follow-up scans and less extensive than the fibrocystic changes seen on chest radiographs. In the two patients studied, thyroid hormone level did not affect the radioiodine lung uptake and there was congruent gallium-67 uptake. None of the patients had any evidence of thyroid cancer recurrence or of reactivation of tuberculosis and only two patients had chronic intermittent chest symptoms. Severe bronchiectasis, active tuberculosis, acute bronchitis, respiratory bronchiolitis, rheumatoid arthritis-associated lung disease and fungal infection such as Allescheria boydii and aspergillosis can lead to different patterns of radioiodine chest uptake mimicking pulmonary metastases. Pulmonary scarring secondary to tuberculosis may predispose to localized radioiodine accumulation even in the absence of clinically evident active infection. False-positive radioiodine uptake due to pulmonary infection/inflammation should be considered in thyroid cancer patients prior to the diagnosis of pulmonary metastases.
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PMID:Radioiodine uptake in inactive pulmonary tuberculosis. 1036 53

We describe three patients with well-differentiated thyroid carcinoma in whom no rise in serum thyroid-stimulating hormone (TSH) was observed after the discontinuation of thyroid hormone. In one patient, TSH deficiency was due to panhypopituitarism secondary to the empty sella syndrome. This patient initially failed to respond to (131)I but was subsequently given purified porcine TSH prior to further (131)I therapy. This resulted in a significant fall in the thyroglobulin level. In two further patients, TSH levels were suppressed by functioning follicular thyroid cancer. There was an unexpectedly good (131)I uptake by metastases and they responded clinically. The failure of TSH levels to rise after thyroid hormone withdrawal should prompt investigation of the pituitary-thyroid axis. In patients with hypopituitarism, exogenous TSH is recommended, to increase the (131)I uptake. In contrast, when TSH is suppressed by functioning tumour, radio-iodine treatment may still be effective.
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PMID:Failure of TSH rise prior to radio-iodine therapy for thyroid cancer: implications for treatment. 1047 25

Recombinant human TSH has been developed to facilitate monitoring for thyroid carcinoma recurrence or persistence without the attendant morbidity of hypothyroidism seen after thyroid hormone withdrawal. The objectives of this study were to compare the effect of administered recombinant human TSH with thyroid hormone withdrawal on the results of radioiodine whole body scanning (WBS) and serum thyroglobulin (Tg) levels. Two hundred and twenty-nine adult patients with differentiated thyroid cancer requiring radioiodine WBS were studied. Radioiodine WBS and serum Tg measurements were performed after administration of recombinant human TSH and again after thyroid hormone withdrawal in each patient. Radioiodine whole body scans were concordant between the recombinant TSH-stimulated and thyroid hormone withdrawal phases in 195 of 220 (89%) patients. Of the discordant scans, 8 (4%) had superior scans after recombinant human TSH administration, and 17 (8%) had superior scans after thyroid hormone withdrawal (P = 0.108). Based on a serum Tg level of 2 ng/mL or more, thyroid tissue or cancer was detected during thyroid hormone therapy in 22%, after recombinant human TSH stimulation in 52%, and after thyroid hormone withdrawal in 56% of patients with disease or tissue limited to the thyroid bed and in 80%, 100%, and 100% of patients, respectively, with metastatic disease. A combination of radioiodine WBS and serum Tg after recombinant human TSH stimulation detected thyroid tissue or cancer in 93% of patients with disease or tissue limited to the thyroid bed and 100% of patients with metastatic disease. In conclusion, recombinant human TSH administration is a safe and effective means of stimulating radioiodine uptake and serum Tg levels in patients undergoing evaluation for thyroid cancer persistence and recurrence.
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PMID:A comparison of recombinant human thyrotropin and thyroid hormone withdrawal for the detection of thyroid remnant or cancer. 1056 23

A diagnostic iodine-131 (131I) total body scan (TBS) is usually recommended 6 to 12 months after thyroid ablation for differentiated thyroid carcinoma. Its usefulness was evaluated in 256 consecutive patients treated and followed up at the Institut Gustave Roussy for papillary (n = 200), well differentiated (n = 27), or poorly differentiated (n = 29) follicular thyroid carcinomas. All patients underwent a near-total or total thyroidectomy and 131I ablation with 3.7 GBq (100 mCi). No TBS was performed before 131I ablation. The TBS performed after the administration of 131I to destroy the thyroid remnants showed uptake (<2%) limited to the thyroid bed. A diagnostic 131I-TBS was obtained after withdrawal of T4 treatment, with either 74 MBq (2 mCi; n = 82) or 185 MBq (5 mCi; n = 174), 6 to 12 months after initial treatment, with serum thyroglobulin (Tg) determination. No interference in the Tg assay was found in these 256 patients. Uptake in the thyroid bed was not detected (total ablation) in 236 patients, was visible but too low to be measured in 19 patients, and attained 1% in only 1 patient. No uptake was found outside the thyroid bed. The serum Tg level, once thyroid hormone treatment had been withdrawn, was below 1 ng/mL in 210 patients, ranged from 1-10 ng/mL in 31 patients, and was above 10 ng/mL in 15 patients. A 131I-TBS performed with 3.7 GBq in nine patients with a Tg level above 10 ng/mL, showed foci of uptake outside the thyroid bed in three patients; lung metastases were demonstrated by a CT scan in another patient, and palpable lymph node metastases were found in one patient. In conclusion, a diagnostic 131I-TBS with 74-185 MBq performed 1 yr after thyroid ablation demonstrated no abnormal uptake; it did not correlate with results of Tg determination and only confirmed the completeness of thyroid ablation. The serum Tg level obtained after withdrawal of T4 treatment permits the selection of patients with a Tg level exceeding 10 ng/mL, for scanning with 3.7 GBq (100 mCi).
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PMID:Is diagnostic iodine-131 scanning useful after total thyroid ablation for differentiated thyroid cancer? 1115 80

The optimal treatment of metastatic thyroid cancer that produces high amounts of thyroid hormone has not been well defined. A 46-yr-old woman presented with a follicular thyroid carcinoma arising from a struma ovarii with hepatic metastases. After the removal of both the struma and the thyroid gland, the liver metastases showed evidence of a high degree of hormonogenesis. Brain, chest, abdomen, and bone imaging was negative for additional metastases. Because iodine uptake by most thyroid carcinomas is quite low in the absence of high levels of ambient TSH, we used recombinant human TSH (rhTSH) (Thyrogen) to achieve a concentration of 131I activity in the tumor high enough for a significant cytotoxic effect. After rhTSH administration (0.9 mg im daily for 2 consecutive days), a 131I diagnostic whole body scan confirmed the existence of 17 discrete hepatic foci of 131I uptake. To calculate the amount of 131I that would deliver an absorbed radiation dose that would be optimally cytotoxic to the metastases (>8000 rad/lesion) and not to the normal liver, we performed lesion dosimetry. Analysis of dosimetric data showed that 15 of 17 lesions would receive an adequate radiation dose following the administration of 65 mCi of 131I. Additionally, we performed whole body dosimetry to assure that this dose would not cause bone marrow toxicity. The patient was reevaluated 6 months after therapy; the liver metastases showed significant, but partial, response. In conclusion, we used the combination of rhTSH with lesional and whole body dosimetry for the treatment of highly functional metastases from follicular thyroid carcinoma arising within a struma ovarii. This strategy can be applied to determine a safe and effective dose of 131I for the treatment of any thyroid cancer metastases that produce enough TH to preclude stimulation of endogenous pituitary TSH secretion.
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PMID:Recombinant human thyrotropin for the diagnosis and treatment of a highly functional metastatic struma ovarii. 1063 93

Metoxyizobutyloizonitrile labelled with technetium 99mTc is a radio-pharmaceutical that was shown to accumulate in benign and cancerous thyroid tissue. As it can be applied without thyroid hormone withdrawal this gave a stimulus to the investigations on its usefulness in diagnostic and follow up procedures for thyroid cancer patients. The goal of this study is to evaluate the efficacy and benefit of 99mTc-MIBI whole body scintigrams in post surgery follow-up of patients with differentiated thyroid cancer. One hundred and twenty eight 99mTc MIBI scintigraphy were performed and evaluated. Sensitivity of MIBI scans was the highest for bone metastases--79%. Good results were also obtained for lymph node metastases (sensitivity--73%, specificity--90%). In case of lung metastases the sensitivity and specificity were 21% and 94% respectively. Sensitivity of detection of clinically apparent recurrent disease in thyroid bed was 70% and specificity of visualization 78%. Results of our study demonstrate that 99mTC-MIBI is valuable tool in follow up of thyroid cancer patients, but can not replace 131I scintygraphy.
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PMID:[The usefulness of MIBI scintigraphy for postoperative monitoring of patients with thyroid cancer]. 1069 99

Well-differentiated (follicular and papillary) thyroid carcinoma accounts for 80% to 90% of the approximately 28,000 new cases each year and the estimated 376,000 existing cases of primary thyroid cancer in Europe and the United States. It is among the most curable neoplasms, but 5% to 20% of survivors develop local or regional recurrences, and <5% to 10% distant metastases, generally in the first years of follow-up, but sometimes after many years. Outcome of patients with recurrent or metastatic disease is highly dependent on the size and extent of neoplastic foci when detected. Because of the long-term risk of recurrence and the importance of timely detection, diagnostic follow-up of well-differentiated thyroid carcinoma is life-long and must be very sensitive. The past three decades have seen great progress in improving the safety, efficacy and convenience of the diagnostic follow-up of well-differentiated thyroid cancer. Three major innovations account for this progress: 1) increased understanding of prognostic factors for disease recurrence and individualization of follow-up according to these factors; 2) the emergence of serum thyroglobulin (Tg) measurement as the principal modality in diagnostic follow-up; 3) and most recently, the introduction of recombinant human thyroid-stimulating hormone (rhTSH) to provide TSH stimulation during thyroid hormone suppression therapy (THST) and to avoid THST withdrawal for Tg testing or iodine-131 (I-131) whole-body scanning. Continued work in these three areas and in new areas will allow the thyroidology community to build on, and patients to benefit from recent progress.
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PMID:Diagnostic follow-up of well-differentiated thyroid carcinoma: historical perspective and current status. 1072 99

Thyroid cancer is a rare malignancy with wide interethnic and geographic variations. In Germany thyroid carcinoma is the 13th most frequent malignancy (2.7 new cases yearly per 100,000 inhabitants). The overall temporal incidence is increasing slightly in recent years. The most common types of cancer are papillary (60-80%) and follicular cancers (10-20%). The relevant prognostic indicators are tumor stage and distant metastases. The mean survival rates in papillary thyroid cancer usually exceed 90%, whereas in follicular thyroid cancer they amount to approximately 80%. The standard treatment procedure in differentiated papillary and follicular thyroid cancer consists of total thyroidectomy followed by adjuvant ablative therapy with radioiodine. Only in papillary thyroid cancer stage pT1N0M0 lobectomy alone is considered to be appropriate. In patients with locally invasive differentiated thyroid cancers stage pT4 adjuvant percutaneous radiation therapy is a treatment option. Radioiodine therapy has to be performed under the stimulative influence of TSH. Usually TSH suppressive medication with Levothyroxine has to be withdrawn approximately 4 weeks prior to radioiodine therapy. In the future, exogenous stimulation by recombinant TSH may be used instead of thyroid hormone withdrawal. It has been proven by different studies that ablative radioiodine therapy reduces the frequency of recurrences and tumor spread in patients with thyroid cancer significantly. In patients with distant metastases, up to 50% of complete responses may be achieved with radioiodine treatment.
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PMID:131I therapy of thyroid cancer patients. 1073 83


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