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)

Both external and internal exposure to radiation have been linked to the development of papillary thyroid cancer. Rearrangement of the gene for RET tyrosine kinase and subsequent expression of this protein has also been found to occur in many papillary thyroid cancers, and with increased frequency in radiation-related cancers following the Chernobyl accident. However, little has been reported on the frequency of RET rearrangements in cancers after exposure to external radiation. We here report on RET protein immunoreactivity in paraffin-embedded thyroid samples from 30 patients with papillary thyroid cancer who received radiation treatment during childhood for benign conditions at Michael Reese Hospital in Chicago, and in 34 patients identified from the tumor registry as having papillary thyroid cancer with no history of therapeutic radiation. The subjects were characterized by sex, age at surgery, and the following attributes of tumor pathology: size, number of lobes involved, number of foci, lymph node metastases, and soft tissue invasion. Representative tissue samples were reacted with an antibody against the RET tyrosine kinase domain whose expression has been shown to correlate highly with RET/PTC rearrangements. A greater percentage of cancers positive for RET immunoreactivity was found in the radiation-exposed group (86.7% vs. 52.9%, P = 0.006). Although the mean age at surgery of the exposed group was lower than the control group, there was no correlation of positive RET immunoreactivity with the age at surgery. No characteristics of the tumors were associated with positive RET immunoreactivity. In summary, the greater incidence of RET-immunopositives in the irradiated group indicates that the expression of RET immunoreactivity is strongly associated with radiation exposure, but the prognostic significance of this is not yet clear.
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PMID:RET expression in papillary thyroid cancer from patients irradiated in childhood for benign conditions. 1216 37

The sodium-iodide symporter (NIS) is expressed by papillary (PTC) and follicular (FTC) thyroid carcinoma, and is essential for iodine uptake. We hypothesized that PTC and FTC with detectable NIS immunostaining would be more amenable to radioactive iodine ((131)I) treatment and follow a more benevolent course. To test this, we determined NIS expression by immunohistochemistry in 23 PTC, 9 FTC, and 12 benign thyroid lesions from children and adolescents. NIS expression was determined by two blinded examiners and graded as absent = 0, minimal = 1, moderate = 2, intense = 3, and very intense = 4. NIS was detected in 35% (eight of 23) of PTC, 44% (four of 9) of FTC, 25% (two of eight) of benign tumors, and 100% (four of four) of autoimmune lesions. The intensity of NIS expression was similar in PTC (0.61 +/- 0.24), FTC (0.56 +/- 0.24), and benign tumors (0.50 +/- 0.33) but was more intense in autoimmune lesions (3.0 +/- 0.7, p < 0.005). Distant metastases were found only among PTC with undetectable NIS (two of 15, 13%), and recurrence developed exclusively from PTC and FTC with undetectable NIS (four of 20, 20% versus zero of 12, p = 0.043). The dose of iodine 131 required to achieve remission in the five patients with PTC who had undetectable NIS (213.3 +/- 53 mCi) was greater than that required by patients with similar age and extent of disease for whom NIS expression is unknown (109 +/- 22 mCi, p = 0.06). We conclude that NIS expression is associated with a lower risk of recurrence for PTC and FTC of children and adolescents.
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PMID:Differentiated thyroid carcinoma that express sodium-iodide symporter have a lower risk of recurrence for children and adolescents. 1240 22

The c-met protein, encoded by the c-met oncogene and its ligand, the hepatocellular growth factor/scatter factor, are known to be responsible for the motility and mitogenesis of epithelial cells including cancer cells. Recent studies have reported the prognostic significance of the c-met protein in malignant tumors. Papillary thyroid carcinoma, the most common histological type of thyroid carcinoma, can easily metastasize to regional lymph nodes, reflecting the activated motility and invasiveness of the carcinoma cells. We examined the expression of c-met protein in papillary thyroid carcinomas to assess its significance. Immunohistochemical staining of the c-met protein was performed on archival materials. The c-met protein was expressed in 10 cases of papillary thyroid carcinoma with recurrence, and in 5 of 10 cases without recurrence. Normal thyroids were negative for c-met protein. Expression of the c-met protein was statistically associated with recurrence of the thyroid carcinoma (p = 0.016). It is suggested that expression of the c-met protein plays a role in the recurrence of papillary thyroid carcinoma.
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PMID:Expression and significance of c-met protein in papillary thyroid carcinoma. 1247 69

Papillary thyroid carcinoma is the most common malignant tumor of the thyroid and usually behaves in an indolent fashion. At most institutions these tumors are treated by near-total or total thyroidectomy followed by radioactive iodine ablation. The 2 main reasons for this extensive treatment include high rate of multicentricity in papillary carcinoma and difficulty in ablating large thyroid remnants with radioactive iodine after partial thyroidectomy. Some authors believe, however, that this treatment protocol may not be justified in all cases of papillary carcinoma. We analyzed 253 total thyroidectomies performed for papillary thyroid carcinoma for the following pathologic variables: tumor size, presence of tumor capsular and/or vascular invasion, intrathyroidal spread, tumor in the contralateral lobe, and lymph node metastases. Tumors measuring less than 1 cm and those with extrathyroidal soft tissue extension were excluded from this study. Among 253 cases (197 females, 56 males, age range 14-88 years), the primary tumor size ranged from 1-9.5 cm; 162 cases were completely encapsulated. Tumor capsule invasion was seen in 139 (86%) and vascular invasion was present in 32 (13%) cases; of these 27 (11% of the total) patients showed both tumor capsule and vascular invasion. Seventy-four (29%) patients showed tumor in the contralateral lobe; in 35 (47%) of these cases the contralateral tumor measured less than 1.0 cm. Lymph nodes were sampled in 106 cases, metastases were present in 67 (67/106 = 63%) and only 16 cases with lymph node metastases showed contralateral tumors. No significant correlation was noted between tumor size, occurrence of contralateral tumors, and lymph node metastases. Seventy-one percent of cases included in this study failed to show contralateral tumors. Hence, pathologic parameters such as lack of vascular invasion and lack of multifocality may be used to identify patients who can benefit from conservative therapy alone.
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PMID:Can we rely on pathologic parameters to define conservative treatment of papillary thyroid carcinoma? 1249 Sep 76

Papillary thyroid carcinoma (PTC), the most common variety of thyroid cancer, is found in a variety of morphologic variants, usually grows slowly, and is clinically indolent, although rare, aggressive forms, with local invasion or distant metastases, occur. Our group has previously demonstrated an association between Hashimoto thyroiditis and ret/PTC-1 activation, and have hypothesised that c-ret activation might be implicated in immune reaction to thyroid epithelium. The objective of this study was to examine expression of the cellular adhesion molecule, E-cadherin, in various thyroid tumor types and Hashimoto thyroiditis in the context of ret/PTC-1 positivity by using laser capture microdissection and TaqMan reverse transcription-polymerase chain reaction (RT-PCR). Variable down-regulation of E-cadherin among carcinomas was demonstrated, with anaplastic carcinomas showing little or no expression. Follicular thyroid carcinomas consistently had significantly decreased E-cadherin expression compared with papillary thyroid carcinomas. The ret/PTC-1-positive papillary thyroid carcinoma (PTCret+) and Hashimoto thyroiditis cases had consistently lower E-cadherin expression levels than the corresponding ret/PTC-1-negative papillary carcinomas (PTCret-), suggesting not only an association between ret activation and the loss of cellular adhesion but also, more significantly, an association between papillary thyroid carcinoma and Hashimoto thyroiditis.
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PMID:Real-time quantitative analysis of E-cadherin expression in ret/PTC-1-activated thyroid neoplasms. 1257 41

Many imaging techniques are available for the evaluation of patients with malignant obstructive jaundice. Ultrasonography, in experienced hands, is valuable for evaluating the local extent of the disease, but its usefulness for staging distant metastases is limited. When used properly, CT and MR imaging can provide valuable information about the extent of local tumor involvement and distant metastases. These noninvasive techniques provide images of the bile ducts and vascular images that are comparable in quality to those obtained with more invasive procedures, such as PTC, ERCP, and angiography, and do not have the risk for complications of these invasive techniques.
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PMID:Preoperative imaging of biliary tract cancers. 1260 76

The prognostic significance and the optimal management of regional lymph node metastases in patients with well-differentiated thyroid carcinoma continue to be controversial. The current surgical approach for nodal metastases is removal of grossly involved lymph nodes ("berry picking"). In patients with papillary thyroid cancer, this intraoperative sampling technique reveals tumor in only 15% to 60% of excised nodes. However, if a more extensive nodal dissection is undertaken, at least 70% of patients are found to have nodal disease. The authors have successfully used a gamma probe-guided lymph node dissection technique ("gamma picking") to identify visually undetectable micrometastatic lymph nodes at the time of surgical exploration. The authors used this technique in a 52-year-old man with papillary carcinoma of the thyroid that was diagnosed by fine-needle aspiration. Eighteen hours before the planned total thyroidectomy, the patient was given 1 mCi I-123 orally. Operative exploration revealed multiple tumor nodules in both lobes but no palpable lymph nodes in the neck. Total thyroidectomy was performed with complete extracapsular removal of both lobes and isthmus. The thyroid bed and the central and lateral nodal basins were scanned using a gamma probe (Neoprobe). Hot spots were identified, and these counts were compared with that of the background activity in the strap muscles. The gamma probe revealed four distinct foci of increased activity (10 times more than the background). These were resected and labeled separately for histopathologic study. Histologic analysis revealed bilateral, multifocal well-differentiated papillary carcinoma, with the largest tumor focus measuring 0.6 cm. Two of the four hot spots proved to be metastatic foci in small lymph nodes measuring less than 0.5 cm. The other two hot spots were thyroid remnants with no associated nodal tissue.
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PMID:Gamma probe-guided lymph node dissection ('gamma picking') in differentiated thyroid carcinoma. 1260 62

BACKGROUND: Although direct infiltration of papillary carcinoma of thyroid to larynx, trachea and esophagus is well recognized, lymphatic and vascular metastases to larynx and hypopharynx have rarely been reported. CASE REPORT: A case of loco-regionally advanced papillary carcinoma of thyroid metastasizing to the hypopharynx and aryepiglottic fold is presented CONCLUSIONS: Papillary thyroid carcinoma (PCT) is known for their indolent nature and erratic behavior. PCT commonly spreads through lymphatics and vascular spread is rare. However, when occurs it is usually to bone, brain, lungs and soft tissue. Therapeutic decisions in advanced thyroid malignancies are usually difficult especially when there is extra-nodal spread of the tumor. A judicious combination of surgical clearance combined with radioablation is the key to the management of such tumors
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PMID:Unusual metastasis of papillary thyroid carcinoma to larynx and hypopharynx a case report. 1287 94

In contrast to vascular endothelial growth factor (VEGF), which stimulates angiogenesis, VEGF-C is thought to stimulate lymphangiogenesis. The role of VEGF-C in thyroid cancer pathogenesis has not been clarified. One might expect a different pattern of VEGF-C expression in the various types of thyroid cancer because of their different means of metastases. In this investigation, we determined whether the differential expression of VEGF-C might explain the different propensity to lymph node metastasis in thyroid cancers. One hundred eleven normal and neoplastic thyroid tissues were analyzed by real-time quantitative PCR. Papillary thyroid cancers had a higher VEGF-C expression than other thyroid malignancies (P < 0.0005 ANOVA). Among the normal thyroid tissues from patients with malignant or benign thyroid diseases, there was no significant difference in VEGF-C expression. Paired comparison of VEGF-C expression between thyroid cancers and normal thyroid tissues from the same patients showed a significant increase of VEGF-C expression in papillary thyroid cancer (1.10 +/- 0.41 vs. 0.70 +/- 0.13; P = 0.001) and a significant decrease of VEGF-C expression in medullary thyroid cancer (0.11 +/- 0.13 vs. 0.78 +/- 0.29; P = 0.001). In contrast, there was no significant difference of VEGF-C expression between cancer and normal tissues in other types of thyroid cancer. In summary, VEGF-C expression is increased in papillary thyroid cancer, compared with paired normal thyroid tissues, but not in other thyroid cancers that are also prone to lymph node metastasis. The lymphangiogenic role of VEGF-C in thyroid cancers therefore appears to be complex and other factors are likely to be also involved.
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PMID:Expression of vascular endothelial growth factor-C in benign and malignant thyroid tumors. 1291 57

The purpose of this study was to assess the feasibility of sentinel lymph node (SLN) biopsy in thyroid neoplasms. Ten patients with uninodular thyroid disease and no evidence of lymph node metastases were examined. Lymph node mapping was performed by preoperative lymphoscintigraphy and intraoperative use of a hand-held gammaprobe. Following thyroidectomy, the SLN(s) were selectively excised and worked-up histologically for occult metastases. Overall detection of SLNs was possible in 50% of the cases with lymphoscintigraphy and in 100% with the gammaprobe. All SLNs in the lateral compartment and upper mediastinum were accurately detected with lymphoscintigraphy. One patient with a papillary carcinoma showed a metastasis in the SLN. One patient experienced temporary lesion of the recurrent laryngeal nerve. In conclusion, sentinel lymph node biopsy is technically feasible. The combination of lymphoscintigraphy and gammaprobe accurately reveals SLNs in the central and lateral compartment and in the mediastinum. Search for SLNs in the lower central compartment enhances the risk of injuring the recurrent laryngeal nerve. The clinical relevance of SLN biopsy in papillary thyroid cancer is unclear, and the subgroup of patients benefiting from it has still to be defined.
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PMID:Sentinel lymph node biopsy in thyroid tumors: a pilot study. 1293 12


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