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)

The cloning of the calcium sensing receptor (CaR) confirmed that parathyroid cells monitor extracellular calcium concentration ([Ca2+]ext) via a receptor-type mechanism. This lead to the hypothesis that abnormalities in the expression and/or function of the CaR could explain the biochemical abnormalities in primary hyperparathyroidism (PHPT). Cultured cells from parathyroid adenomas of patients operated for PHPT were used to monitor real-time changes in intracellular calcium concentration ([Ca2+]i) as measured by fluorescent microscopy using the Fura-2/AM dye. We found that CaR agonists trigger release of intracellular calcium pools and such responses are amplified by increasing the affinity of IP3 receptors. Using confocal microscopy to monitor membrane trafficking in living parathyroid cells labelled with the fluorescent dye FM1-43, we found that a decrease in [Ca2+]i rather than an absolute change in [Ca2+]ext is the main stimulus for exocytosis from human parathyroid cells. These data suggest that, in PHPT, a defective signalling mechanism from the CaR allows cells from parathyroid adenomas to maintain low [Ca2+]i with uninhibited PTH secretion in the face of hypercalcaemia. Over longer periods of time, CaR controls parathyroid proliferation via changes in tyrosine phosphorylation. We found that multiple proteins of molecular weight 20-65 kDa are phosphorylated within 10-60 min in response to CaR agonists. Further work demonstrated that high [Ca2+]i stimulates the expression of bcl-2 oncoprotein in cultured human parathyroid cells and that, in parathyroid adenomas, predominant expression of bcl-2 rather than bax oncoprotein might prevent apoptosis and explain the slow growth rate of these tumours. More recently, it became apparent that CaR stimulates cell proliferation in several cell types not involved in calcium homeostasis. Using archived histological material from 65 patients who died with metastatic breast cancer, we identified CaR expression predominantly in tumours from patients who developed bone rather than visceral metastases (35 of 49 versus 7 of 16; P < 0.01, chi-squared test). These data suggest that CaR expression has the potential to become a new biological marker predicting the risk of bone metastases in patients with breast cancer. A prospective study should investigate if patients with CaR-positive tumours are more likely to develop bone metastases and whether they could benefit more from prophylactic treatment with bisphosphonates or the newly developed CaR antagonists.
 ...
PMID:The calcium sensing receptor: from understanding parathyroid calcium homeostasis to bone metastases. 1849 87

Gastrinoma tissue has been found frequently in lymph nodes located near the duodenum without a known primary tumor. Therefore, it has been suggested that a primary lymph node gastrinoma exists. We report on a 38-year-old woman suffering from multiple endocrine neoplasia type 1 (MEN1) confirmed by menin gene mutation analysis. MEN1 disease started with primary hyperparathyroidism followed by Cushing disease, the detection of tumors of the pituitary, adrenal cortex, and the pancreas and also an elevated serum gastrin level. An octreotide scan revealed 4 tumors in the upper abdomen. A selective arterial calcium stimulation test located the source of the hypergastrinemia to the area of the gastroduodenal and the superior mesenteric arteries. Total pancreatoduodenectomy was performed and conventional histopathologic examination revealed a well-differentiated cystic neuroendocrine tumor of the pancreas expressing glucagon and accompanied by several microadenomas. In addition, 3 suprapancreatic lymph nodes with gastrin-positive endocrine tissue were found. None of the pancreatic microadenomas expressed gastrin and no duodenal endocrine tumor was found despite careful macroscopic examination. Only after complete embedding of the duodenal and pancreatic tissue in 65 paraffin blocks, 2 microgastrinomas (0.45 and 0.8 mm in diameter) were identified in the duodenum. It is concluded that duodenal gastrinomas that give rise to lymph node metastases may be so tiny that they are easily overlooked in a routine examination and that systematic tissue monitoring is required to identify them.
 ...
PMID:Primary lymph node gastrinoma or occult duodenal microgastrinoma with lymph node metastases in a MEN1 patient: the need for a systematic search for the primary tumor. 1852 Apr 36

We report a 47-year-old women who presented to her general practitioner and our hospital with weight loss of unknown etiology. Eight years previously she had undergone a hemithyroidectomy for nodular goiter with one cold nodule. Laboratory results revealed hypercalcemia, evidence of primary hyperparathyroidism and computer tomography of the thorax showed bilateral pulmonary metastasis. After undergoing CT-guided biopsy of a metastasis, histology revealed an endocrine primary tumor with low parathyroid hormone expression. In view of the history, clinical and biochemical findings we diagnosed a recently metastasized functioning parathyroid carcinoma, which eight years previously has been labeled as a benign atypical thyroid adenoma. The patient underwent surgical resection of all detected metastases. Afterwards the serum calcium and parathyroid hormone levels normalized. Parathyroid carcinoma is an uncommon tumor. In the absence of pathognomonic diagnostic criteria a definitive pathological diagnosis of parathyroid carcinoma often is not possible. The treatment of parathyroid carcinoma is essentially surgical. Patients with parathyroid carcinoma mostly die from uncontrollable hypercalcemia rather than from other tumor-related complications.
 ...
PMID:[Rare cause of hypercalcemia]. 1921 66

Raw Cystic parathyroid adenoma is a rare cause of primary hyperparathyroidism. The authors report one case of cystic parathyroid adenoma, who presented with progressive right hip pain for one year. The patient had severe hypercalcemia at the first presentation and was misdiagnosed as having metastatic cancer at first. An iliac bone biopsy was performed and showed a giant cell tumor. Parathyroid hormone level was evaluated later and was found to be high, 1,555 pg/ml (15-65 pg/ml). An MRI study of the neck was done and revealed a cystic mass 38 x 36 x 40 mm in diameter just below the left lower pole of the thyroid gland. Tc-99m MIBI scan demonstrated increase and retention of radioactivity uptake at the same area. Hyperfunctioning parathyroid gland was considered. Parathyroidectomy was done and histopathology revealed cystic parathyroid adenoma. Serum calcium was normal and hip pain was markedly improved after the surgery.
 ...
PMID:Primary hyperparathyroidism due to cystic parathyroid adenoma: a case report. 1923 Apr 28

The relationship of hypercalcemia with cancer is well described in the literature. Breast cancer is the commonest malignancy associated with hypercalcemia; the detection of hypercalcemia in these patients usually signifies metastatic disease and is associated with a poor prognosis. However, the treating oncologist should keep in mind that a strong correlation exists between breast cancer and primary hyperparathyroidism. We present a case of a patient of treated breast cancer who, in the absence of metastatic bone disease, developed hypercalcemia due to hyperparathyroidism secondary to a parathyroid adenoma.
 ...
PMID:Hypercalcemia and treated breast cancers: the diagnostic dilemma. 1929 90

RET codon 609 point mutations are rare and may predispose to aggressive medullary thyroid carcinoma (MTC). In a kindred with 15 carriers of the Cys609Ser RET mutation we observed no MTC before 17 years of age, no lymph node metastases before 30 years and no distant metastases before 60 years. Two patients developed pheochromocytoma and one had primary hyperparathyroidism as the first sign of the syndrome. In conclusion, at variance from what already known, in this large kindred the Cys609Ser RET mutation predispose to a scarcely aggressive, highly penetrant MTC and a low penetrance of pheochromocytoma and primary hyperparathyroidism.
 ...
PMID:Characterization of the largest kindred with MEN2A due to a Cys609Ser RET mutation. 1947 97

Malignant insulinomas are rare tumors (10% of insulinomas) that often present as mnulticentric macro nodules with multiple liver metastases before diagnosis. We report the case of a 55 year old female with a medical history of severe hypoglycemic attacks for two months. Blood tests showed a decreased value of glycemia (30 mg/dl) associated with increased insulin level (l6 microU/ml) and an increased glycemia/insulinemia ratio of 1.87 supporting the diagnosis of insulinoma. Abdominal CT showed a 1.5 cm mass localized in the head of the pancreas with disseminated hepatic tumors, confirmed as neuroendocrine metastases by biopsy (which proved the presence of a malignant insulinoma). Primary hyperparathyroidism was diagnosed based on mild elevation of calcium (10.4 mg/dl) associated with a high level of PTH (71.2 pg/ml). The coexistence of the two endocrinopathies suggested the presence of type 1 multiple endocrine neoplasia (MEN 1). Because of multiple hepatic masses and liver function impairment, surgery and hepatic artery embolization were not performed. Somatostatin analog therapy was started with symptomatic control in the beginning, but rapid loss of beneficial effect. Finally, systemic chemotherapy with doxorubicin was administered, but the disease was progressive and after three months we decided to stop it. The patient died at home after one month, probably in hypoglycemic coma.
 ...
PMID:Malignant insulinoma with hepatic and pulmonary metastases associated with primary hyperparathyroidism. Case report and review of the literature. 2010 68

Parathyroid cancer is an uncommon malignancy and rare cause of primary hyperparathyroidism (HPT) with a high morbidity and patient death in advanced cases usually resulting from intractable hypercalcemia. Inactivation of the HRPT2/CDC73 gene, encoding the putative tumor-suppressor protein parafibromin and discovered in the context of the hyperparathyroidism-jaw tumor (HPT-JT) syndrome, is a common, somatic event in most parathyroid cancers. Approximately 25% of patients with apparently sporadic parathyroid cancer carry germline HRPT2/CDC73 mutation. Germline DNA analysis for HRPT2/CDC73 mutation is recommended in all patients with parathyroid cancer because of the potential benefit for first-degree relatives, who should nevertheless undergo serum calcium screening. The histopathologic diagnosis of parathyroid cancer is nonspecific unless vascular, lymphatic, capsular, or soft tissue invasion is seen, or metastases are clinically evident. Immunohistochemical analysis of parathyroid tumors for loss of parafibromin expression offers promise as a diagnostic tool. En bloc tumor resection offers the highest chance of cure in patients with suspected parathyroid carcinoma. No adjuvant chemotherapy regimen has yet proven effective, and the role of local adjuvant radiotherapy is being evaluated. Metastatic disease can be palliated with surgical debulking. Medical therapy with the calcimimetic cinacalcet and bisphosphonates can ameliorate hypercalcemia in patients with inoperable disease.
 ...
PMID:Parathyroid cancer. 2116 77

A 29-year-old man presented to his primary care physician with nausea, severe weight loss and muscle weakness. He had a hard, fixed neck swelling. He was severely hypercalcaemic with 10-fold increased parathyroid hormone (PTH) concentrations. A diagnosis of primary hyperparathyroidism was established and the patient was referred for parathyroidectomy. At neck exploration, an enlarged parathyroid gland with invasive growth into the thyroid gland was found and removed, lymph nodes were cleared and hemithyroidectomy was performed. A suspected diagnosis of parathyroid carcinoma was confirmed histologically. Serum calcium and PTH levels normalised post-operatively, but hyperparathyroidism recurred within 3 years of surgery. Over the following 17 years, control of hypercalcaemia represented the most difficult challenge despite variable success achieved with repeated surgical interventions, embolisations, radiofrequency ablation of metastases and treatment with calcimimetics, bisphosphonates and haemodialysis using low-dialysate calcium. In this paper, we report the challenges and pitfalls we encountered in the management of our patient over nearly two decades of follow-up and review recent literature on the topic.
 ...
PMID:Challenges and pitfalls in the management of parathyroid carcinoma: 17-year follow-up of a case and review of the literature. 2125 29

Intrathyroidal parathyroid carcinoma is extremely rare clinical entity with potentially multiple diagnostic pitfalls. We report a case of 40-year-old man presented with classical manifestations of primary hyperparathyroidism, severe hypercalcemia and profoundly increased serum parathyroid hormone level. Neck ultrasonography demonstrated multinodular goiter with predominant 34 mm nodule in left thyroid lobe. Additional 16 mm nodule was found beneath the left lobe. Routine percutaneous fine-needle aspiration of predominant nodule indicated follicular thyroid carcinoma, while left inferior nodule was confirmed to be of parathyroid origin. The patient underwent surgery, during which frozen sections identified medullary thyroid carcinoma with metastasis to upper mediastinal lymph node. Permanent sections of the predominant left lobe nodule revealed intrathyroidal parathyroid carcinoma surrounded with multiple microscopic metastases. Left inferior nodule was metastatic lymph node. Additional 10 mm intrathyroidal metastasis of primary parathyroid carcinoma was found within right thyroid lobe. This case indicates that fine-needle-aspiration and intraoperative biopsy are of limited value in diagnosing parathyroid carcinoma, especially if localized intrathyroidally. Oncological en-block resection is treatment of choice, implying ipsilateral lobectomy in case of thyroid invasion. This firstly described case of intrathyroidal parathyroid carcinoma causing intrathyroidal dissemination may influence future treatment strategies.
 ...
PMID:Intrathyroid parathyroid carcinoma with intrathyroidal metastasis to the contralateral lobe: source of diagnostic and treatment pitfalls. 2174 52


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