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)

The intention of this prospective study was to compare the diagnostic potential of technetium-99m sestamibi (MIBI) and a novel radiotracer, 99mTc-Tetrofosmin (Tetro), for the assessment of primary nasopharyngeal carcinoma (NPC) and the differentiation of residual disease from post-therapy changes. A total of 38 patients underwent MIBI and Tetro single-photon emission tomography (SPET) imaging at initial presentation (n=22) or following therapy (n=16). The findings were correlated with computed tomography or magnetic resonance imaging (MRI) on a site-by-site basis. Tumour/background (Tm/Bkg) ratios were obtained on coronal sections. Biopsy (nine patients) and/or 12- to 24-month clinical follow-up data were available in the post-therapy group. All primary disease sites were accurately detected by both imaging studies. Although there was no statistical difference between the two imaging techniques in the detection of primary disease, MIBI was superior to Tetro in the detection of regional lymph node metastases (sensitivity: 95% vs 79%). Tetro and MIBI SPET were true-positive in all patients (n=7) with proven residual/recurrent disease. In nine patients who had no evidence of residual/recurrent tumour, MRI was false-positive in five while Tetro and MIBI SPET were false-positive in two and three patients, respectively. Tm/Bkg ratios were </=1.7 in all false-positive cases except one. Tetro, MIBI and MRI had specificities of 78%, 67% and 44%, and accuracies of 87.5%, 81% and 69%, respectively. The results of Tetro and of MIBI SPET were not statistically different from one another with regard to the prediction of residual/recurrent or metastatic NPC.
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PMID:A comparative study of technetium-99m sestamibi and technetium-99m tetrofosmin single-photon tomography in the detection of nasopharyngeal carcinoma. 916 68

99mTc-Tetrofosmin (TF) is a lipophilic diphosphine compound routinely used for myocardial scintigraphy. Extracardiac utilization has occurred in evaluation of patients with malignant neoplasms and in parathyroid adenomas. Although its uptake mechanisms are not completely understood, they appear similar to those of 99mTc Setamibi (MIBI). The importance of flow and the metabolic status of cells with an intracellular uptake depending on mitochondria and the Na+/K+ pump have been hypothesized. It has also been demonstrated that Tetrofosmin shares with MIBI the property of being a substrate for P-glycoprotein (P-gp), a multidrug resistance transporter. In this review the possible clinical role in breast cancer is analysed. First experiences suggest that scintimammography with TF is useful in patients with indeterminate Mammography and to obtain complementary data to avoid surgery and/or biopsy. TF is a reliable tracer for diagnosis of primary cancer, of local recurrence of axillary lymph node metastases. Preliminary data stimulate a possible role in functional imaging of chemoresistance and in differential diagnosis of distant metastases with main reference to the evaluation of single hot lesions at bone scan.
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PMID:Diagnostic and prognostic role of 99mTc-Tetrofosmin in breast cancer. 927 32

In the follow up of differentiated thyroid carcinoma (DTC) several scintigraphic methods are used in addition to the serum thyroglobulin and ultrasonography of the neck. Iodine-131 whole body scintigraphy (WBS), which is performed since many years, is able to detect iodine positive recurrence, lymph node metastases and distant metastases in a very specific way. However, the problem of I-131 WBS is the fact that only 67% of metastases from DTC accumulate iodine. Therefore non specific radionuclides like TI-201 or tracers such as Tc-99m Sestamibi or Tc-99m Tetrofosmin and new metabolic tracers like F-18 FDG were introduced in the diagnostic work up to detect iodine negative metastases as well. This study describes the comparison of different tracers in 35 patients with elevated thyroglobulin and suspicion of metastatic disease or already known metastases from DTC.
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PMID:Comparison of different tracers in the follow up of differentiated thyroid carcinoma. 1052 27

Iodine-131 is the most specific radionuclide to follow up patients with differentiated thyroid cancer (DTC). However there are some aspects that should be considered if 131I whole body scintigraphy (131I WBS) is performed. 1) Several prior conditions, including a bTSH above 30 mU/l and an urinary iodine excretion below 100-150 micrograms/g Crea, should be fulfilled. 2) Only about two thirds of metastases from DTC accumulate iodine. Therefore, in addition to 131I WBS, there is a need for other nonspecific tracers such as 99mTc Tetrofosmin WBS, 99mTc Sestamibi WBS or F-18 FDG PET to detect also iodine negative recurrences or metastases. There new tracers, especially F-18 FDG PET have demonstrated a very high detection rate of iodine negative metastases with mostly low differentiation. 3) The sensitivity of 131I WBS depends on the administered dose. Whereas the sensitivity of a diagnostic 131I WBS (up to 185 MBq) is below 60%, the value for a post-therapeutic 131I WBS (after 3700-7400 MBq) increases up to 75%. This means that in case of elevated serum thyroglobulin, iodine positive metastases cannot be excluded until WBS after 131I therapy is performed. 4) In patients with elevated serum thyroglobulin and/or known metastases, who are scheduled for 131I treatment, the question arises whether a diagnostic 131I WBS should be performed and if so, which dose should be administered to avoid thyroid stunning. There is evidence in the literature that the dose for a pre-therapeutic diagnostic 131I WBS should not exceed 74 MBq. 5) Despite the high specificity of 131I WBS, several pitfalls of iodine accumulation in non-malignant diseases and malignancies of other origin than thyroid cancer should be taken into account.
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PMID:131I whole body scintigraphy in thyroid cancer patients. 1056 34

Hypofunctioning nodules on scintiscan using Tc-99m Pertechnetate or I-123 have a higher probability of malignancy compared to eu- or hyperfunctioning nodules. However, in the preoperative assessment of thyroid nodules, ultrasonography and ultrasonography guided fine needle aspiration biopsy play the most important role, especially for papillary thyroid cancer. The problem of differentiating follicular adenoma from highly differentiated follicular carcinoma however remains. Also the additional use of a multi tracer imaging strategy (Tl-201/Tc-99m subtraction scan, Tc-99m Sestamibi, Tc-99m Tetrofosmin dual phase scintigraphy) has not solved this problem. Although it is unlikely, the question whether FDG PET is able to give a better differentiation between benign and malignant tumours in the preoperative assessment of thyroid nodules is not answered up to now. In contrast to preoperative diagnostics, FDG PET is of great value in the postoperative follow up of differentiated thyroid cancer. In case of elevated serum thyroglobulin but negative I-131 WBS FDG PET is the method of choice to detect I-131 negative recurrences and metastases. FDG uptake in metastases from differentiated thyroid cancer is correlated to low differentiation and maybe bad prognosis. There is also evidence that FDG PET may have a role in the follow up of anaplastic and especially in medullary thyroid cancer in the future.
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PMID:The role of F-18FDG PET in thyroid cancer. 1081 62

Technetium-99m-tetrofosmin is a radiopharmaceutical employed for myocardial imaging, which has recently emerged as useful in the visualization of tumors. In this study technetium-99m-tetrofosmin was evaluated for its accuracy in differentiating malignant from benign pulmonary lesions, and in detecting mediastinal node metastasis due to lung cancer. Eighty-one patients with a solitary lung lesion on the chest radiograph and/or CT scan were submitted to chest single photon emission computed tomography after technetium-99m-tetrofosmin injection (740 MBq i.v.). The scintigraphic findings were correlated to the final histopathological diagnosis, demonstrating abnormal tracer accumulation in 51 of 54 malignant lesions (sensitivity 94%) and in 4 out of 27 benign conditions (specificity 85%), yielding an accuracy of 91%. Mediastinal lymph-node involvement was evaluated in 35 patients with non small cell lung cancer who underwent mediastinoscopy and/or surgery. Tetrofosmin accuracy (89%) was significantly higher than that of CT (69%, p < 0.05); the false negative scintigraphic results were in nodes sized less than 1 cm. In conclusion, technetium-99m-tetrofosmin imaging is useful in distinguishing malignant from benign pulmonary lesions, and in non-invasively assessing mediastinal node metastases from non small cell lung cancer, especially in patients with enlarged nodes by CT scan.
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PMID:Technetium-99m tetrofosmin single photon emission computed tomography in the evaluation of suspected lung cancer. 1085 Feb 96

In the preoperative assessment of thyroid nodules, ultrasonography and ultrasonography-guided fine needle aspiration biopsy play the most important role, especially for papillary thyroid cancer. The problem to differentiate follicular adenoma from highly differentiated follicular carcinoma remains the problem in preoperative diagnostic. Also the additional use of a multi tracer imaging strategy (Tl-201/Tc-99 m subtraction scan, Tc-99 m Sestamibi, Tc-99 m Tetrofosmin dual phase scintigraphy) has not solved this problem. Although it is unlikely, the question whether F-18-fluorodeoxy-glucose-positron emission tomography is able to give a better differentiation between benign and malignant tumors in the preoperative assessment of thyroid nodules is not answered up to now. In contrast to preoperative diagnostics F-18-fluorodeoxyglucose-positron emission tomography is of great value in the postoperative follow up of differentiated thyroid cancer. In case of elevated serum thyroglobulin but negative I-131 WBS F-18-fluorodeoxy-glucose-positron emission tomography is the method of choice to detect I-131 negative recurrences and metastases. F-18-fluorodeoxy-glucose uptake in metastases from differentiated thyroid cancer is correlated to low differentiation and maybe bad prognosis. There is also evidence that F-18-fluorodeoxyglucose-positron emission tomography may have a role of in anaplastic and especially in medullary thyroid cancer in the future.
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PMID:[Value of F-18 fluorodeoxyglucose positron emission tomography in thyroid carcinoma]. 1213 56

Differentiated thyroid cancer is a rare tumour with an incidence of 4 - 9/100,000/year. For preoperative assessment of thyroid nodules, ultrasonography (US) and US-guided fine needle aspiration biopsy are the methods of choice to detect thyroid cancer. The value of preoperative fluorine-18 fluorodeoxyglucose positron emission tomography (18F-FDG-PET) in differentiating malignant from benign nodules, especially in cases of follicular proliferation, has not yet been evaluated. After thyroidectomy and radioiodine remnant ablation, several methods are used to follow patients with differentiated thyroid cancer, including serum thyroglobulin, ultrasonography of the neck, iodine-131 (131I) whole body scintigraphy (WBS) and scintigraphy with nonspecific tracers such as technetium-99 m ((99m)Tc) Tetrofosmin or Sestamibi. Whereas the specificity of 131I-WBS is high, sensitivity is low, especially if one takes into account that only two-thirds of recurrences or metastases store iodine. With the introduction of 18F-FDG in oncology, it is also used for the detection of local recurrences and metastases of differentiated thyroid cancer. Elevated thyroglobulin but negative 131I-WBS belongs to the 1a indications for 18F-FDG-PET in oncology according to the German Consensus Conference 2000. The sensitivity for detecting 131I-negative metastases with 18F-FDG-PET can be increased by elevated thyroid-stimulating hormone (TSH) after withdrawal of thyroid hormone therapy or after intramuscular injection of recombinant TSH. Most of the 131I-negative metastases demonstrate 18F-FDG uptake, which represents rapid tumour growth and poor differentiation, whereas most of the 131I-positive metastases are 18F-FDG negative. The combination of 131I-WBS and 18F-FDG-PET leads to an increase in the detection rate to more than 90 - 95 % in cases of elevated thyroglobulin, because well- and less-differentiated cancer cells may be present in one patient. In rare cases, a recurrent tumour or metastasis may accumulate 131I as well as 18F-FDG. In these patients, it may be possible that well- and less-differentiated cells are present in one metastasis. The early use of 18F-FDG-PET in patients with elevated thyroglobulin, especially in the case of negative 131I-WBS, changes the therapeutic strategy in up to half of the patients (surgery, external radiation).
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PMID:18F-FDG-PET in the follow-up of thyroid cancer. 1255 61

For early diagnosis of thyroid cancer, ultrasonography (US) and US-guided fine-needle aspiration biopsy are the methods of choice. Thyroid scintigraphy using Tc-99m pertechnetate can underline the necessity of surgery in case of hypofunctioning nodules. Treatment of thyroid cancer includes total thyroidectomy and staging lymphadenectomy, in the case of lymph node metastases, radical neck dissection of the ipsilateral side. Four weeks after surgery, if TSH exceeds a value of 50 mU/l, with the exception of papillary thyroid cancer pT1a (TNM 1997), radioiodine remnant ablation using activities between 2960 and 3700 MBq I-131 is performed in all other cases. As growth of benign and malignant thyroid cells depends on TSH stimulation, thyroid hormone therapy using TSH suppressive doses (TSH, <0.03 mU/l) follows radioiodine remnant ablation. Additional fractionated external radiation therapy (50 Gy) may be administered in advanced cases (e.g., pT4 N1M0; TNM 1997). Standard follow-up of differentiated thyroid cancer includes measurement of serum thyroglobulin, US of the neck and I-131 whole-body scintigraphy (I-131 WBS). With about 98% the sensitivity of thyroglobulin is very high under TSH stimulation. In case of elevated thyroglobulin, US is the method of choice to detect local recurrences and lymph node metastases of the neck. At defined intervals of follow-up or in case of increasing thyroglobulin, I-131 WBS will be performed under TSH stimulation. With the availability of recombinant TSH (exogenous TSH stimulation) the need to withdraw thyroid hormone over a period of 3-4 weeks (endogenous TSH stimulation) is no longer necessary to perform I-131 WBS. However, in about 20-40% of cases or in the course of disease after several radioiodine therapies, recurrences or metastases may be or become iodine negative. In this case, cationic complexes such as Tc-99m Sestamibi or Tc-99m Tetrofosmin are available to detect less differentiated metastases. In the course of dedifferentiation of malignant thyroid cells, the ability of iodine uptake decreases and uptake of glucose increases. This elevated glucose metabolism can be imaged using FDG PET. Today the combination of PET (metabolic imaging) and CT (morphologic imaging) using PET/CT fusion imaging is the method of choice to image iodine-negative metastases.
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PMID:[Diagnosis, treatment and follow-up in the case of differentiated thyroid cancer]. 1642 98

In order to investigate the clinical significance of (99m)Tc-Tetrofosmin (TF) scintigraphy in the evaluation of lung cancer and mediastinal lymphoid node involvement, 33 patients with pulmonary neoplasmas were subjected to both (99m)Tc-TF scintigraphies and CT scans in one week before their operations or puncturations. All the images were judged visually and the emission images were analyzed with semi-quantitative methods in addition. The results of each group were compared. There was marked difference in target/non-target (T/N) ratio between the lung cancer group and the benign lesion group (P<0.001). Moreover, in the lung cancer group, T/N ratio in tomographies was significantly higher than that in planar images (P<0.01). The sensitivity and accuracy of semi-quantitative analysis in (99m)Tc-TF SPECT were significantly higher than those of CT in the diagnosis of pulmonary neoplasmas (P<0.05 and P<0.01 respectively), so was the sensitivity of (99m)Tc-TF SPECT vs CT in the diagnosis of mediastinal lymphoid node metastasis (P<0.05). It was also found that epidermoid squamous cell carcinomas and adenocarcinomas had a higher T/N ratio than in small cell carcinomas (P<0.05), and 2 h washout rate (WR) of adenocarcinomas was higher than that of epidermoid squamous cell carcinomas (P<0.05). In conclusion, (99m)Tc-TF scintigraphy showed a favorable diagnostic accuracy in appraising lung cancers and mediastinal lymph node metastases. Furthermore semi-quantitative technology can improve the accuracy, and is potential to offer some information about histological type of the cancer tissue. Therefore, (99m)Tc-TF scintigraphy will be a useful tool in the diagnosis and staging of lung cancer.
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PMID:The clinical usefulness of (99m)Tc-Tetrofosmin scintigraphy in the diagnosis of lung neoplasmas and mediastinal lymphoid node involvement. 1884 50


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