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)

Struma ovarii (SO) is usually asymptomatic and only in a few cases it is associated with thyrotoxicosis. The presurgical diagnosis is very uncommon. In the majority of cases a pelvic mass is discovered at physical examination or by abdominal ultrasound. Only the hystopathologic examination is able to reveal the characteristic features of SO, with thyroid cells organized in follicles as the main tumoral tissue constituent. The histologic recognition of malignancy is not easy and usually requires an exhaustive sampling of the lesion to evaluate the extracapsular invasion. We report the case of a 59-year-old woman who came to our observation for the fortuitous finding of elevated serum thyroglobulin (Tg) levels (600-800 ng/mL). Because the thyroid function was normal and the ultrasound showed only a subcentrimetric nodule, the clinical suspicious of a SO was considered. Ultrasound examination of the abdomen showed a solid mass of 2 cm in the left ovary. A (131)I uptake was observed at scintiscan in the site of the solid mass. Three months after the resection of the left ovary serum Tg levels were markedly reduced (106 ng/mL), and its values continued to decrease down to 34 ng/mL at last control. The histology showed that the ovarian mass was mainly constituted of thyroid tissue (98%), with no malignant features. The molecular analysis of several thyroid differentiation gene mRNAs in the SO tissue showed an abundant expression of all genes but pendrin (PDS). A reduced PDS mRNA expression might explain the defective thyroxine (T(4)) production. Despite the absence of malignant features, the expression of RET/PTC3 rearrangement was found, raising the possibility of a potential malignant nature of the tumor. A cancer-free period of 3-4 years, as in our patient, is not long enough to definitively exclude a late onset metastatic disease but, unfortunately, the patient died of nonmedical reasons. In conclusion, we report a case of SO that, to our knowledge, is the first in which the clinical suspicion arose from the inappropriately elevated presurgical serum levels of Tg. A quite exhaustive molecular analysis of thyroid specific genes and oncogenes provided two interesting findings: the low PDS mRNA expression, which may explain the low hormonal production and the absence of thyrotoxicosis and the presence of a RET/PTC3 rearrangement, which prompts the possibility of a late malignant evolution.
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PMID:RET/PTC3 rearrangement and thyroid differentiation gene analysis in a struma ovarii fortuitously revealed by elevated serum thyroglobulin concentration. 1640 8

Papillary carcinoma is the most common type of thyroid malignancy. It has been recently shown that these tumors commonly have one of three genetic alterations: BRAF point mutations, RET/PTC rearrangements, or RAS point mutations. In this study, we analyze the relationship between these alterations and the microscopic features of papillary carcinomas, their clinical features, and prognostic characteristics. Ninety-seven papillary carcinomas were studied; in all cases, frozen tissue was available for nucleic acid extraction. Of 96 unselected cases, 42% were positive for BRAF, 18% for RET/PTC, and 15% for RAS mutations. Morphologic features were evaluated in detail in 61 cases and 6 characteristic nuclear features and 3 additional microscopic features were assessed quantitatively. At least 4 nuclear features were found in each tumor, with nuclear pseudoinclusions being the least frequent finding in all mutation groups. BRAF mutations were associated with older patient age, typical papillary appearance or the tall cell variant, a higher rate of extrathyroidal extension, and more advanced tumor stage at presentation. RET/PTC rearrangements presented at younger age and had predominantly typical papillary histology, frequent psammoma bodies, and a high rate of lymph node metastases. Tumors with RAS mutations were exclusively the follicular variant of papillary carcinoma and correlated with significantly less prominent nuclear features and low rate of lymph node metastases. These findings demonstrate that BRAF, RET/PTC, and RAS mutations are associated with distinct microscopic, clinical, and biologic features of thyroid papillary carcinomas.
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PMID:Correlation between genetic alterations and microscopic features, clinical manifestations, and prognostic characteristics of thyroid papillary carcinomas. 1643 96

The goal in managing patients who have MTC is to detect and surgically remove disease at an early stage. Tumor marker-based biochemical screening and DNA-based genetic screening have created the opportunity for effective prophylactic surgery in patients at risk for hereditary MTC. Complete surgical resection is critical for cure because cervical reoperation for persistent or recurrent disease benefits only select patients. With the advent of therapies that target the RET-activated pathways, new hope may be emerging for patients who have locally advanced or metastatic disease.
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PMID:Medullary thyroid cancer. 1688 2

Heterotopic intrathymic thyroid tissue is an extremely rare condition, but it is important to distinguish it from metastases of clinically undetected thyroid carcinoma because metastatic papillary thyroid carcinoma is often so well differentiated, simulating normal thyroid tissue. Described herein are histological findings of heterotopic intrathymic thyroid tissue that was incidentally identified in a woman with papillary thyroid carcinoma during histological examination of a radical neck dissection specimen. These findings emphasize that this rare incidence may occur and should be differentiated from metastatic papillary carcinoma. Histologically, the patient's intrathymic thyroid follicles were identical to the normal thyroid follicles, having flat cuboidal cells with uniformly small nuclei without nuclear grooves or inclusions. The follicular cells had a low Ki-67 labeling index close to zero, and immunonegativity for galectin-3, HBME-1, and RET oncoprotein, in contrast to the tumor cells in primary papillary thyroid carcinoma of the patient. To the authors' knowledge this is the first case report of intrathymic heterotopic thyroid tissue posing a diagnostic difficulty in a patient with papillary thyroid carcinoma.
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PMID:Heterotopic intrathymic thyroid tissue. 1698 21

Medullary thyroid carcinoma (MTC) is a rare malignancy of the thyroid C cells. It occurs in hereditary (25% of cases) and sporadic forms, and aggressiveness is related to the clinical presentation (hereditary vs. sporadic) and the type of RET mutation present. In hereditary cases, early diagnosis makes preventative surgery possible. In established cases, thorough surgical extirpation of the primary tumor and nodal metastases has been the mainstay of treatment. Radioactive iodine, external beam radiation therapy (EBRT), and conventional chemotherapy have not been effective. Newer systemic treatments, with agents that target abnormal RET proteins, hold promise and are being tested in clinical trials for patients with metastatic disease.
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PMID:Current approaches to medullary thyroid carcinoma, sporadic and familial. 1713 4

A series of biochemical parameters are useful for the diagnosis and follow-up of differentiated thyroid carcinomas. The measurement of serum thyroglobulin (Tg) is considered for the post-surgical/radioiodine follow-up of papillary/follicular carcinomas. Other than in basal conditions, the importance of Tg levels during TSH stimulation is underlined, either by discontinuation of L-T4 therapy or by recombinant human TSH test. The finding of undetectable Tg levels during TSH stimulation is highly correlated with clinical remission; otherwise, peak Tg levels > 1-2 ng/ml can be suggestive of recurrence/persistence of the disease. The accuracy of Tg measurements for the detection of metastases seems to be higher when compared to 131-1 whole-body scan. The evaluation of basal serum calcitonin levels is recommended for the screening of medullary thyroid carcinoma (MTC). High basal levels suggest the presence of a tumor but a calcitonin increase can be observed also in parafollicular C cell hyperplasia (CCH) and other extra-thyroidal conditions. The pentagastrin test can by pass this obstacle as the calcitonin response seems to be typical of pathological thyroid C cells. The cut-off value of calcitonin response between patients with MTC and CCH remains to be established; the latter condition, however, being considered by some authors as pre-cancerous. After thyroid surgery the measurement of calcitonin constitutes a valid tool for the detection of cure and/or recurrence of the disease. The screening by means of RET oncogene analysis is also described for patients with MTC with Multiple Endocrine Neoplasia (MEN) type 2 syndrome.
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PMID:[Useful and limits of the biochemical markers for the diagnosis of thyroid carcinoma]. 1713 35

Papillary and follicular carcinomas, commonly referred to as follicular cell-derived differentiated thyroid carcinomas (DTC), account for 90% of all thyroid carcinomas. The prognosis of DTC is generally good, depending on the biologic behavior of the tumor and on the appropriate initial treatment which includes total thyroidectomy and ablation by radioiodine-131. However, a considerable number of patients, approximately 30%, as shown after 30 years of follow-up, have recurrent disease. It is thus of utmost importance to evaluate the prognostic factors, as derived from retrospective studies, and identify high risk patients. Age of more than 45 years or less than 25 years is a particularly strong independent prognostic factor; on the contrary gender is a poor prognostic factor. Histological type of the cancer especially tall cancer cells and columnar cancer cells, as well as increased vascular invasion of the tumor, lymph-node and distant metastases, are all considered as risk factors that can lead to poor prognosis. Combined prognostic factors have been used to form scoring systems (SS) such as AGES, MACIS, AMES, EORTC and TNM for a more precise description of high or low risk patients. However, prognostic significance of the SS is limited, since they do not take into consideration the clinical status or the treatment procedure during the course of the disease. Molecular factors such as rearrangements of genes RET/PTC, RAS mutations and fusion of, paired box and 8/peroxisome proliferator-activated receptor gamma (PAX8/PPARgamma) are also involved in thyroid cancer prognosis, while some others: human Pituitary- Tumor Transforming Gene (e.g. MIB-1, hPTTG) have been reported as additional prognostic factors. In this review we describe the risk and the prognostic factors of DTC as related to management and the outcome of DTC.
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PMID:Risk and prognostic factors for differentiated thyroid cancer. 1881 68

Medullary thyroid carcinoma (MTC) is a rare malignancy of the thyroid C cells. It occurs in hereditary (25% of cases) and sporadic (75%) forms. Sporadic MTCs frequently metastasize to cervical lymph nodes. Thorough surgical extirpation of the primary tumor and nodal metastases by compartment-oriented resection has been the mainstay of treatment (level IV evidence). Surgical resection of residual and recurrent disease is effective in reducing calcitonin levels and controlling complications of central neck disease (level IV evidence). Radioactive iodine, external beam radiation therapy, and conventional chemotherapy have not been effective. Newer systemic treatments, with agents that target abnormal RET proteins hold promise and are being tested in clinical trials for patients with metastatic disease.
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PMID:Evidence-based approach to the management of sporadic medullary thyroid carcinoma. 1742 1

Approximately 10% of thyroid cancers are present in patients less than 21 years of age, representing 3% of all cancers of children and adolescents, with predominance in females 2:1 in relation to males. Thyroid cancers in this age group are usually papillary (90%), bilateral, multifocal and bigger in size compared to adults. Capsule invasion and lymphatic and pulmonary metastases are more frequent in children. Radiation sensitivity seems to represent an important factor in prepubertal patients. Familial history is reported in 5% of the cases. Genes such as RET/PTC, RAS and BRAF are usually involved in thyroid carcinogenesis in this age group. Cervical adenomegaly is a common clinical presentation, but does not represent a poor prognostic factor in children. Ultrasound and fine needle aspiration biopsy are valuable diagnostic procedures. Surgery is the preferred treatment including thyroidectomy and ganglionary excision, followed by ablative radioiodine therapy. L-thyroxine replacement with suppressive dosage should be employed targeting chronic TSH suppression. Long-term prognosis is usually better in children when compared with adults. Plasma thyroglobulin measurement is also useful to detect residual thyroid cancer disease.
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PMID:[Thyroid carcinoma in children and adolescents]. 1789 Dec 39

Medullary thyroid carcinoma (MTC) accounts for up to 8% of all thyroid cancers. Although primary surgery is curative in the vast majority of patients treated at an early stage, disease can persist or recur with deleterious effects on quality of life. Local and distant metastases can occur and are the major causes of mortality. Reoperation, embolization, and perhaps radiotherapy can improve the outcome for some patients who are not cured by primary surgery, but there is a need for novel treatments. No comprehensive clinical trial data are available on conventional cytotoxic agents for the treatment of MTC. Patients with distant metastases, in particular, might benefit from several novel compounds directed against angiogenesis and molecular targets in tumor cells, such as products of the proto-oncogene RET and mutants of it, and other signaling components. Well-conducted clinical trials are needed to assess and optimize these treatment strategies, and this article outlines how such trials should be conducted. Although RET mutations are common in hereditary MTC and can occur in some cases of sporadic MTC, knowledge of other molecular defects associated with the development of MTC should reveal new targets for therapy.
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PMID:New therapeutic approaches to treat medullary thyroid carcinoma. 1808 43


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