Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

With the variety of radiopharmaceutical agents and refined imaging techniques, thyroid and parathyroid imaging provides much valuable clinical information. The use of imaging is most important in the follow-up of differentiated (DTC) and medullary thyroid cancer (MTC). Patients with DTC are followed with serum thyroidglobulin and 131I whole body scintigraphy when the serum thyroglobulin level is elevated. When the 131I scintigram is negative, 201Tl scintigraphy may best identify the site of recurrent DTC. Alternative radioisotopes, ultrasound, CT, and FDG PET are also useful in localizing the site of DTC metastases. MTC recurrences and metastases are more difficult to image. Selective venous catheterization is the most sensitive and specific method for detecting areas of recurrent MTC. High-resolution ultrasound, CT, MR imaging, and scintigraphy are all capable of, and useful in, detecting macroscopic foci of metastatic tumor. Somatostatin receptor scintigraphy and 99mTc DMSA have been the most frequently used nuclear imaging agents in patients with recurrent MTC. Imaging for hyperparathyroidism remains controversial. Sestambi has become the preferred isotope for parathyroid scintigraphy; whereas high-resolution ultrasound is also frequently used. Preoperative imaging is being used as a method to allow a unilateral neck exploration, more recently, in conjunction with intraoperative 1-84 PTH assay and with intraoperative use of the gamma probe. Most often, parathyroid imaging is performed before reoperation for persistent hyperparathyroidism.
 ...
PMID:The use of imaging studies in the diagnosis and management of thyroid cancer and hyperparathyroidism. 982 66

Assessment of the malignant potential of parathyroid tumors in the absence of metastases can be difficult using morphologic criteria alone. In this study we have examined a total of 58 parathyroid tumors (31 benign, 15 malignant, and 12 equivocal) from 54 patients using immunohistochemistry with monoclonal antibodies directed against the retinoblastoma (RB) protein and the cell cycle-associated antigen Ki-67 to evaluate their role as diagnostic markers. RB protein immunoreactivity was not useful for distinguishing between benign and malignant parathyroid tumors. Analysis of the proliferation marker Ki-67 showed that there was a trend toward more intense staining in the malignant cases. The Ki-67 labeling index was highest in the parathyroid cancers (median 33) and lowest in the sporadic primary adenomas (median 2). An observation that might have clinical implications is that tumors from patients with familial hyperparathyroidism linked to chromosome 1q showed a high Ki-67 index, indicating strong proliferative activity (median 25). This correlates well with the clinical observation of tumors with malignant potential in this syndrome. Because of the considerable overlap between groups of tumors, Ki-67 is not suitable for definitive differentiation between benign and malignant tumors. However, Ki-67 may give valuable information about which patients should be followed more closely.;1999>
 ...
PMID:Evaluation of retinoblastoma and Ki-67 immunostaining as diagnostic markers of benign and malignant parathyroid disease. 984 66

Prediction of evolution of secondary hyperplasia and tumours of the parathyroid glands is still a problem in histopathology. To assess whether the quantity of silver-stained nucleolar organiser region (AgNOR) proteins might be used as a prognostic tool in parathyroid pathology, a standardised AgNOR analysis has been performed on 19 cases of parathyroid hyperplasia caused by secondary hyperparathyroidism (PH), 8 cases of adenoma (PA) and 10 cases of carcinoma (PC). Clinico-pathological data and follow-up information were available. On formalin-fixed and paraffin-embedded sections, the visualisation and quantification of AgNORs were achieved according to the 1995 guidelines of the Committee on AgNOR Quantification. Then, the mean area (square micrometres) of AgNORs per nucleus (NORA) was evaluated by means of an image analyser and specific softwares. After testing the normal distribution of NORA values, statistical parametric tests were utilised; Kaplan-Meier and Cox multivariate analyses were also performed. In parathyroid lesions, a progressive increase of mean NORA values was observed from PH (2.895 microm2; SE 0.171) through PA (3.638 microm2; SE 0.125) to PC (4.701 microm2; SE 0.179); these differences were highly significant (P<0.001), although some degree of overlap was found among single NORA values. A significantly higher mean NORA value was revealed in PC with distant metastases than was noted in cases with no current clinical evidence of disease progression. Furthermore, a significantly (P<0.001) higher mean NORA value was encountered in the group of PH with recurrences (3.600 microm2; SE 0.106) than in nonrecurrent PH (2.261 microm2; SE 0.087). Multivariate analyses indicated that the NORA value was an independent prognostic parameter determining the risk of recurrence in PH. We suggest that AgNOR quantity may be a promising additional tool for predicting the biological behaviour of parathyroid lesions.
 ...
PMID:AgNOR quantity as a prognostic tool in hyperplastic and neoplastic parathyroid glands. 1103 51

A review of all reports in the literature of parathyroid carcinoma (PTC) was undertaken to define an optimal management strategy for this rare condition. PTC is uncommon and its etiology of PTC is largely unknown although patients with familial hyperparathyroidism, multiple endocrine neoplasia type 1 and irradiation to the head and neck are at increased risk for developing the disease. PTC occurs with equal frequency in both sexes and is usually diagnosed in the fifth decade. En bloc resection of the carcinoma and the adjacent structures in the neck is the surgical treatment and is associated with an 8% local recurrence rate and a long term overall survival rate of 89% (mean follow up 69 months). In contrast simple parathyroidectomy results in a 51% local recurrence rate and 53% long-term survival rate (mean follow up 62 months). Adverse prognostic factors for survival were initial management with simple parathyroidectomy alone, the presence of nodal or distant metastatic disease at presentation and non-functioning PTC.
 ...
PMID:Parathyroid cancer: biology and management. 1111 66

The major phenotypes of multiple endocrine neoplasia type 1 (MEN 1) consist of three lesions characterized by hyperparathyroidism, pituitary tumors, and endocrine pancreatic tumors. The endocrine pancreatic tumors are a significant cause of disease-related mortality in MEN 1. Although symptomatic pancreatic tumors such as insulinoma and gastrinoma should be resected, the management of asymptomatic pancreatic tumors is not established. In asymptomatic pancreatic tumors, the most important factor is the propensity for malignant transformation of the tumors. Although there are no means to foresee it, the size of the pancreatic tumors might be predictive of malignant development in MEN 1. We report here a patient with MEN 1 who had a large asymptomatic pancreatic tumor. The patient (72-yr-old man) was diagnosed with primary hyperparathyroidism and underwent a total parathyroidectomy. Genetic examination showed a germline mutation of the MEN1 gene (E45G). Abdominal magnetic resonance imaging revealed a large (>6 cm) tumor with a heterogeneous pattern in the tail of the pancreas. No metastases of the tumor were evident. Serum levels of insulin, gastrin, and glucagon were normal, and the patient had no symptoms. Operative resection was performed, and microscopic examination revealed that the tumor was an islet cell tumor stained with multiple hormones. This is a case indicating that asymptomatic pancreatic tumors associated with MEN 1 might be indolent independent of their size.
 ...
PMID:Large and asymptomatic pancreatic islet cell tumor in a patient with multiple endocrine neoplasia type 1. 1121 36

Medullary carcinoma of the thyroid (MTC) is a rare tumour derived from thyroid C cells with serum calcitonin as a specific and sensitive marker. MTC is inherited in 25% of cases, with an autosomal dominant transmission, age-related penetrance and variable expressivity. MTC is an obligatory component of multiple endocrine neoplasia type 2 (MEN2), which comprises three well defined syndromes: MEN2A, which may be associated with pheochromocytoma and/or hyperparathyroidism; the much rarer MEN2B, which occurs early and is accompanied by developmental abnormalities; while in contrast, familial MTC (FMTC) is not associated with any endocrinopathy. The RET proto-oncogene is the causative gene of the MEN2 syndromes and mutations in this gene are found in >90% of inherited cases, allowing easier and more reliable family screening than pentagastrin stimulation tests. Nevertheless, the correlation between the genotype and the different clinical phenotypes is not perfect. The prognosis of MTC depends on its staging at presentation, and the early appearance of cervical lymph node metastases emphasizes the need for extensive surgery, although many patients still do not normalize calcitonin levels post-operatively, and they remain a challenge for the further management.
 ...
PMID:Diagnosis and treatment of medullary thyroid cancer. 1128 39

The association between primary hyperparathyroidism and nonmedullary thyroid malignancies is well known. There is also, however, some evidence for an association between secondary hyperparathyroidism (SHPT) and thyroid cancer. We report three patients in whom invasive papillary thyroid carcinoma (PTC) was diagnosed before (one case) or at the time of (two cases) parathyroidectomy for SHPT. Three women (ages 23, 54, and 64 years) presented with bone pain and pruritus typical of SHPT. All three patients had biopsy-proven parathyroid bone disease and elevated parathormone levels (664, 1674, and 2051 pg/mL). All underwent subtotal parathyroidectomy and total thyroidectomy without complications. Pathology revealed diffuse parathyroid hyperplasia with multifocal invasive papillary thyroid carcinoma (two cases) and follicular variant of papillary thyroid carcinoma (one case). Two cases were associated with metastatic disease to local lymph nodes. The patients received adjuvant radioactive 131I, and remained tumor free 24 to 36 months after surgery with complete resolution of SHPT. We conclude: 1) PTC may accompany SHPT, 2) PTCs associated with SHPT may be locally aggressive although usually they are early tumors, 3) surgeons need to have an index of suspicion for thyroid tumor when operating on patients with SHPT, and 4) routine removal of the thymus as part of the operation for SHPT may have a secondary benefit in diagnosing PTC in the occasional patient.
 ...
PMID:Secondary hyperparathyroidism: evidence for an association with papillary thyroid cancer. 1137 34

Parathyroid carcinoma is a very rare malignancy and the least common among endocrine malignat tumors. Its etiology is still unclear and some hypotheses have been suggested: previous external radiation to the neck, pregression from benign to malignant lesion, familial hyperparathyroidism. An early accurate diagnosis is very important since surgery is the most effective therapeutic approach to parathyroid carcinoma. Prognosis is quite variable and stress is laid on the early diagnosis and radical surgery which seem to be most favorable prognostic factors. An accurate follow-up should include frequent measurements of serum calcium and PTH levels to promptly detect recurrence or metastases which are usually associated with severe hyeprcalcemia.
 ...
PMID:Parathyroid carcinoma. A concise review. 1147 35

Clodronic acid is a non-aminate bisphosphonate capable of inhibiting bone resorption. Pharmacological and clinical trials have shown the efficacy of clodronic acid in the treatment of post-menopausal osteoporosis and in all conditions of excess bone resorption, such as Paget's disease, malignant tumoral hypercalcemia and osteolytic metastases. Clodronic acid is the only bisphosphonate currently on the market available for both oral and parenteral administration. Intramuscular therapy with clodronic acid at a dose of 100 mg/week has shown significant effects on bone mineral density after 6 months treatment in patients with postmenopausal osteoporosis and these effects were maintained 3 years after the start of treatment. Increased bone mass is associated with a reduced risk of the onset of vertebral fractures. In a recent three-year study a significant increase was observed in bone mineral density associated with a 46% reduction in the incidence of vertebral fractures. The reduction in bone pain after parenteral treatment with clodronic acid is an important added value in the use of this molecule in osteopenic pathologies. Moreover the costs of parenteral clodronic acid treatment is certainly competitive compared to other drugs. Oral and parenteral clodronic acid was well tolerated in clinical trials. Gastrointestinal adverse effects were described only with high oral doses. These effects were transient and generally resolved without interrupting the treatment. Clodronic acid is an effective and well tolerated drug able to inhibit bone resorption. The low incidence of undesired effects at a gastroenteric level, the possibility of formulas for parenteral administration, the antalgic effect and low costs make clodronic acid an extremely interesting molecule for the prevention and treatment of postmenopausal osteoporosis and all conditions of excessive bone resorption, such as Paget's disease, malignant tumoral hypercalcemia, osteolytic metastasis and hyperparathyroidism.
 ...
PMID:[Use of clodronic acid in mineral metabolism conditions: state of the art in 2000]. 1153 69

Osteitis fibrosa cystica (brown tumors) can be a skeletal manifestation of advanced hyperparathyroidism, including parathyroid cancer. Severe osteitis fibrosa cystica can mimic metastatic bone diseases especially in patients with a history of cancer. Because the treatment and prognosis of these two problems differ greatly considering hyperparathyroidism in the differential diagnosis of patients found to have osteolytic lesions is critical for the appropriate management of these patients. In this case report we describe a patient with a history of renal cell cancer and presumed osteolytic bone metastases. During prophylactic intramedullary rodding to prevent pathologic fracture of her femur she was found to have a benign lesion related to her previously undiagnosed hyperparathyroidism caused by an underlying parathyroid cancer. A detailed review of this disease and the associated bone changes is also included to underscore the importance of an adequate differential diagnosis as well as optimal management. Patients with hypercalcemia or bony lesions should not automatically be treated palliatively for metastatic disease just because of a past medical history of cancer. Hyperparathyroidism is a readily curable problem if properly diagnosed.
 ...
PMID:Disseminated brown tumors from hyperparathyroidism masquerading as metastatic cancer: a complication of parathyroid carcinoma. 1160 52


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>