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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
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PMID:Parathyroid carcinoma. A concise review. 1147 35

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.
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PMID:Disseminated brown tumors from hyperparathyroidism masquerading as metastatic cancer: a complication of parathyroid carcinoma. 1160 52

Parathyroid carcinoma is an uncommon malignancy. Of the fewer than 400 cases reported, most have been cases of producing parathyroid carcinoma with accompanying hypercalcemia. Only 13 patients with nonproducing parathyroid carcinoma have been described. Nine of these 13 patients had metastatic disease. We report a patient with i.c. metastasis. Distal metastases of producing parathyroid carcinoma are treated surgically to prolong survival and prevent complications of hyperparathyroidism and hypercalcemia. One half of the patients with producing parathyroid carcinoma die within 5 years, mostly because of the complications of hypercalcemia. Nonproducing parathyroid carcinoma compares unfavorably with producing parathyroid carcinoma in terms of tumor progression and prognosis. Few data on choice of therapy in nonproducing parathyroid carcinoma are available. We treated our patient with a combination of radiotherapy and chemotherapy. Treatment was followed by an unexpectedly prolonged survival of 31 months after diagnosis of metastatic disease.
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PMID:Painful ophthalmoplegia from metastatic nonproducing parathyroid carcinoma: case study and review of the literature. 1177 32

Parathyroid carcinoma is an uncommon endocrine malignancy, with difficult diagnosis. There are several presenting clinical and biochemical features that suggest it: much higher serum calcium and PTH levels than parathyroid adenomas, symptoms of severe hypercalcemia, the classical target organs affected and a palpable neck mass. Pathologic findings, local invasion, lymph node and distant metastases prove the diagnosis. Initial surgical therapy (en bloc dissection) is the only chance for cure it. The management of recurrent and/or metastatic parathyroid carcinoma is also surgical, resulting in significant palliation from hypercalcemia, whereas radiation therapy and chemotherapy are not helpful. Bisphosphonates (drugs that inhibit bone resorption) control acute and chronic hypercalcemia when surgery is not effective or possible. Preoperative localization studies (cervical ultrasound, CT scan, MRI and sestamibi scan) are useful in patients with recurrent or persistent parathyroid cancer.
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PMID:[Diagnostic-therapeutic management of parathyroid carcinoma]. 1259 36

Parathyroid carcinoma accounts for 0.5 to 4.0% of cases of primary hyperparathyroidism. The prognosis depends largely on the extent of successful resection at the time of initial operation. Therefore, early diagnosis before surgery is important. We report 3 cases of primary hyperparathyroidism. The first patient, a 20-year-old uremic female, had refractory hypercalcemia after 5 years of hemodialysis treatment. Hypercalcemia persisted despite repeated parathyroidectomy. Pathology revealed diffuse hyperplasia of the parathyroid glands with focal adenomatous changes. Multiple pulmonary metastases were found later. The second patient, a 45-year-old female with history of nephrolithiasis, presented with severe osteoporosis. She underwent repeated parathyroidectomy for local recurrence. Pathology disclosed typical features of parathyroid carcinoma with adjacent lymph node metastasis. The third patient, a 34-year-old male, had recurrent episodes of extremity fracture and hypercalcemia with palpable neck mass. He underwent resection of the parathyroid tumor. Vascular and capsular invasions were noted microscopically. All three patients were relatively young and had extremely high intact parathyroid hormone (iPTH) level (15 to 31 times the upper limit of normal). The first patient died of hypercalcemia and respiratory failure and the other 2 were treated successfully with surgical excision and, in case 2, combined chemotherapy and radiotherapy. The latter 2 patients had no recurrence during 18 months and 14 months of follow-up, respectively. Our experience with these cases suggests that the combination of the following characteristics are highly suggestive of parathyroid carcinoma: young age, palpable neck mass, concomitant renal and skeletal disease, and extremely high iPTH level in patients with PTH-dependent hypercalcemia.
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PMID:Variability of clinical presentations in three cases of parathyroid carcinoma. 1283 92

Parathyroid carcinoma is a rare cause of primary hyperparathyroidism, and the efficacy of medical therapy and chemo- and radiotherapy is poor in recurrent or metastatic disease. We report the first case of PTH immunization in which tumor shrinkage accompanied hormonal, biochemical, and clinical improvements in a patient with metastatic parathyroid carcinoma.A 50-yr-old woman with refractory parathyroid carcinoma and pulmonary metastases was immunized eight times between February 2001 and December 2003 with bovine and modified human PTH fragments and intact human PTH, mixed with Freund's adjuvant. Total and ionized calcium and PTH levels were assayed weekly for 6 months and regularly thereafter. Thoracic computed tomography scans were performed regularly. Antibodies to all PTH fragments were detected after two immunizations. Baseline PTH and total calcium were 213.0 ng/liter and 13.96 mg/dl, respectively, and remained elevated during the first three immunizations. From the fourth immunization onward, PTH and calcium decreased, and the patient's clinical condition improved markedly. PTH and calcium levels have remained controlled for more than 24 months, and the sizes (surface area) of pulmonary metastases decreased from baseline by 39-71%. This is the first evidence that PTH immunization not only can improve clinical, hormonal, and biochemical measures in parathyroid carcinoma but also has an antitumor effect.
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PMID:Hormonal and biochemical normalization and tumor shrinkage induced by anti-parathyroid hormone immunotherapy in a patient with metastatic parathyroid carcinoma. 1524 Jun 24

Parathyroid carcinoma constitutes less than 1% of primary hyperparathyroidism. The exact etiology is not known. Prior radiation to neck, chronic renal failure and genetic factors are thought to play a role. The male to female ratio is one. Parathyroid carcinomas are slow growing, have a tendency to recur locally and metastasize late. 95% of parathyroid carcinomas are functioning. The major distinguishing features of malignant hyperparathyroidism are presence of a palpable mass in the neck and features of severe hypercalcemia. By far the most important test to diagnose primary hyperparathyroidism is serum level of Immunoreactive PTH. The diagnosis of primary hyperparathyroidism is essentially clinical and biochemical. Biopsy is not necessary before definitive surgery. CT scan appears to be the best investigation for detecting the primary tumor, its local extent and metastases. Most of the symptoms are attributable to hypercalcemia, which needs to be treated aggressively. Early surgery with 'en bloc' resection of the tumor is the only potentially curative treatment. Parathyroid carcinoma is traditionally said to be resistant to radiotherapy. Various chemotherapeutic agents have been used with partial anecdotal responses. The 5-year survival is about 50% and 10-year survival varies from 13-49%.
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PMID:The carcinoma of parathyroid gland. 1531 9

Parathyroid carcinoma is a rare tumor that is responsible for <1% of cases of hyperparathyroidism in most parts of the world. An increased incidence of this tumor has been reported in patients with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome, but the etiology of most other cases is unknown. Parathyroid carcinomas tend to occur a decade earlier than adenomas, and the sex ratio approaches unity in contrast to the female preponderance of adenomas. Most patients with carcinomas present with marked hypercalcemia and are more likely to have associated bone and renal disease than those with adenomas. Although fibrosis and mitotic activity are common in carcinomas, these features are not specific for malignancy. The diagnosis of carcinoma should be restricted to those tumors that show invasion of blood vessels, perineural spaces, soft tissues, thyroid gland, or other adjacent structures or to tumors with documented metastases. Mutations of the HRPT2 gene (1q21-q32), which are responsible for the HPT-JT syndrome, have been implicated in the development of a high proportion of parathyroid carcinomas. A subset of patients with mutation-positive carcinomas have germline mutations of the HRPT2 gene. This finding suggests that some patients with apparent sporadic parathyroid carcinomas may have the HPT-JT syndrome or a variant of this syndrome. Because of the high frequency of local recurrence following incomplete excision, an en bloc resection is the preferred surgical approach for treatment of parathyroid carcinomas.
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PMID:Parathyroid carcinoma: an overview. 1573 73

Parathyroid cancer is a rare endocrine tumor and an uncommon cause of HPT. Advances have been made to identify a promising molecular diagnostic marker for the disease. The use of accurate preoperative imaging modalities would undoubtedly facilitate its management by making an accurate preoperative diagnosis by assessing its invasiveness, and by searching for nodal or distant metastases. The effectiveness of the application of intraoperative PTH assay in the management of this rare condition remains to be seen. Radical surgical treatment offers the best chance of cure, but for patients who have refractory unresectable disease or metastases, the availability of more effective targeted medical therapy may palliate the debilitating symptoms of hypercalcemia, reduce its metabolic complications, and potentially improve survival.
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PMID:Parathyroid cancer. 1688 98

Parathyroid carcinoma (PC) is an uncommon finding, accounting for only 1-2% of patients with primary hyperparathyroidism (HPT), but a relatively higher incidence has been reported in Italy and Japan. The etiology of the tumour remains unclear, but molecular analysis studies have hypothesised the involvement of mutations of several genes in the pathogenesis of PC, including the oncogene cyclin Dl or PRADI located at the chromosome 13, the retinoblastoma and the p53 tumour suppressor gene. The clinical presentation of patients with PC is mainly related to the increased secretion of PTH rather than to the tumour burden. The pre-operative diagnosis of malignancy is very difficult to obtain, and, thus, intra-operative recognition of PC is mandatory. However, reliable signs of malignancy are rarely detectable. Probably, only vascular invasion, that correlates with tumour recurrence and metastases, should be considered useful in confirming malignancy, although both Ki-67 and Cyclin D1 have been recently used to aid in the definitive diagnosis. The en bloc resection of the tumour, together with ipsilateral thyroid lobe and adjacent structures, only if involved, avoiding any capsular rupture of the mass, represents the gold standard of surgical treatment of patients. Although the PC has traditionally been considered as a radioresistant tumour, there are some retrospective data holding a possible benefit from post-operative irradiation. No cytotoxic regimen with proven efficacy is currently available for patients with PC, but since hypercalcemia is ultimately the most frequent cause of death, several studies have suggested the usefulness of bisphosphonates (i.e., clodronate, pamidronate and zoledronate), calcitonin, and calcimimetic agents (i.e., cinacalcet) in patients with PC and severe hypercalcemia. In conclusion, PC is a rare malignancy and the NCDB survey reports an overall five- and ten-year survival rate of 85% and 49%, respectively. However, it is very difficult to predict the clinical behaviour of patients with PC and probably the ultimate prognosis depends on successful resection of the tumour at the initial surgery.
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PMID:Parathyroid cancer: etiology, clinical presentation and treatment. 1721 44


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