SEARCH · PubMed Health

Results for “parathyroid carcinoma”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources

PubMed2003

Minimally invasive parathyroidectomy: 101 consecutive cases from a single surgeon.

BACKGROUND: Intraoperative rapid parathyroid hormone (iPTH) assay is changing parathyroid surgery. One surgeon's experience at a tertiary care hospital was followed as minimally invasive parathyroidectomy (MIP) was adopted. STUDY DESIGN: In this prospective case study, patients underwent technitium 99m sestamibi scanning, iPTH monitoring, and MIP. A sestamibi-directed incision was made, and iPTH was measured preincision, preexcision of abnormal gland(s), and at 5- and 10-minute intervals. MIP was complete after gland(s) was excised and iPTH fell to less than 50% of preoperative levels. Routine discharge was on the day of surgery with daily calcium and calcitriol to minimize outpatient hypocalcemia. Secondary and tertiary hyperparathyroidism patients were excluded. RESULTS: From December 1999 to June 2002, 101 patients underwent MIP. Patients were 27% men and 73% women, with two reoperations. Preoperation laboratory results averaged serum calcium 11.08 (normal 8.5 to 10.5 mg/dL) and parathyroid hormone (PTH) 169 pg/mL (normal 10 to 55 pg/mL). Average iPTH values at operative intervals were 152, 151, 68, and 50 pg/mL, respectively. Operation demonstrated 12% of patients had four-gland hyperplasia, 3% had double adenomas, 2% had parathyroid carcinomas, and 83% had single adenomas. Discharge on the day of surgery occurred in 83% of single-adenoma patients. Postoperative laboratory results averaged calcium 9.4 mg/dL (p < 0.001 versus preoperation) and PTH 48 pg/mL (p < 0.001). Fifteen patients (16%) had elevated PTH after operation, but without elevated calcium levels. One patient had persistant hyperparathyroidism. CONCLUSIONS: MIP with iPTH monitoring is a safe and effective means of treating hyperparathyroidism. This approach allows for limited dissection and early discharge for the majority of patients.

Adolescent↗

PubMed1991

Acute complications in the course of "mild" hyperparathyroidism.

It is generally accepted that some patients affected by mild asymptomatic primary hyperparathyroidism need not be treated with surgery, but may be medically managed without risk. However, our experience regarding 5 of these cases observed in the last two years, suggests a different approach. These patients, initially diagnosed as having mild hyperparathyroidism based on only moderately elevated serum concentrations of calcium and followed medically for years, were referred to us for a sudden worsening of their clinical course. One 35-year-old man presented hemorrhagic gastritis with severe anemia and type II AV block with syncopal attacks. Three women, aged 51, 64 and 65 years, presented with severe hypercalcemia associated with renal failure in two and with marked bone disease in another. In all these cases parathyroid neoplasms were preoperatively localized (by ultrasonography, CT scan and radioactive 201-Tl 99-Tc scan) and surgically removed. Histological examination showed a parathyroid carcinoma in the male patient and single gland enlargements in the three females. A fifth patient, a 65-year-old woman, was referred to us in critical condition: severe hypercalcemia, osteopenia with femur fracture, myocardial infarction and renal failure. She died in a few days, in spite of intensive medical care. These cases suggest that patients with hyperparathyroidism initially diagnosed as "mild" need close medical observation and preferably, in our opinion, should undergo surgery.

Acute Kidney Injury↗

PubMed1989

Parathyroid localization, three-dimensional modeling, and percutaneous ablation techniques.

When available, state of the art noninvasive localization studies should be utilized routinely in previously unexplored patients for localizing parathyroid pathology, even when exceptional surgical experience exists. These studies can both minimize the 3 to 20% incidence of missed pathology and promote an approach of limited neck exploration with consequent lowering of morbidity, complications, and costs. Choice of imaging modalities for localizing these small masses is largely dependent on the level of state of the art of available equipment, the interest and experience of the performing physicians, and the attention to technical detail for each of the modalities at an individual institution. In choosing a single test, CT, and most recently cine CT with three-dimensional modeling, is favored because of higher probability of providing the kinds of information most useful to the surgeon. This includes precise anatomic localization and identification of locations likely to be missed by the surgeon (such as mediastinum, deep neck) and the capability for predicting multiple gland disease, for detecting smaller lesions, and for lower incidence of false-positive results. Ultrasound is attractive because of the low cost and noninvasiveness, and it is particularly sensitive in the thyroid region and upper neck. In difficult cases, CT, cine CT, and ultrasound may be augmented by needle aspiration of fluid for PTH assay. Thallium-technetium scanning and MRI are useful alternatives. In the previously explored patient and in patients with difficult diagnostic problems (such as ectopic adenoma, parathyroid carcinoma), the use of multiple noninvasive studies is strongly recommended, preferably CT (particularly, cine CT with three-dimensional imaging) and isotope scanning or MRI. The concurrence of two or more of these studies has a relatively high predictive value (82 to 88%) for localization. However, highly selective venous catheterization and selective magnification arteriography remain the most accurate modalities in these patients (91 to 95% sensitivity with few false-positive results) and may be combined with interventional radiologic techniques for tumor ablation in selected patients without compromising subsequent surgical alternatives. Stereotactic ablation techniques are in development.

Catheterization, Peripheral↗

PubMed2003

Calcimimetic agents: review and perspectives.

BACKGROUND: Recognition of the role of the extracellular calcium-sensing receptor (CaR) in mineral metabolism has greatly improved our understanding of calcium homeostasis. The activation of this receptor by small changes in the extracellular ionized calcium (ec(Ca2+)) regulates PTH, calcitonin secretion, urinary calcium excretion, and, ultimately, bone turnover. METHODS: The cloning of the CaR and the discovery of mutations that make the receptor less or more sensitive to calcium have allowed a better understanding of several hereditary disorders characterized by either hyperparathyroidism or hypoparathyroidism. The CaR, able to amplify the sensitivity of the CaR to Ca++ and suppress PTH levels with a resulting decrease in blood Ca++, became an ideal target for the development of compounds, the calcimimetics. Experience with the calcimimetic R-568 in patients with primary and secondary hyperparathyroidism and parathyroid carcinoma are summarized. RESULTS: The first clinical studies with the first-generation calcimimetic agents have demonstrated their efficacy in lowering plasma intact PTH concentration in uremic patients with secondary hyperparathyroidism. However, the low bioavailability of these first calcimimetics predicts a difficult clinical utilization. The second-generation calcimimetic, AMG 073, having a better pharmacokinetic profile, appears to be effective and safe for the treatment of secondary hyperparathyroidism, suppressing PTH levels while simultaneously reducing serum phosphorus levels and the calcium x phosphorus product. CONCLUSION: The advantage of controlling PTH secretion without the complications related to hypercalcemia, hyperphosphatemia, and increased calcium x phosphorus product is very promising.

Aniline Compounds↗

PubMed1999

Parathyroid cancer: biology and management.

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.

Adolescent↗

PubMed1994

Parathyroid imaging with technetium-99m-sestamibi: an initial institutional experience.

BACKGROUND: The ideal method for preoperative localization of abnormal parathyroid glands has yet to be determined. Technetium-99m-sestamibi, previously used for myocardial perfusion studies, has recently been introduced for parathyroid imaging. METHODS: From August 1991 to September 1993, 44 patients underwent Tc-99m-sestamibi scanning (45 scans) and surgical exploration for hyperparathyroidism at our institution. These 44 patients form the database for this retrospective study. Twenty-eight patients had persistent hyperparathyroidism, six had recurrent disease, three had prior thyroid operation, and seven underwent first time neck operations. The nature of disease was complex and varied: single gland, 26; primary hyperplasia, 5; multiple endocrine neoplasia type 1, 5; familial, 3; secondary or tertiary, 5. One patient with single gland disease and one patient with multiple endocrine neoplasia type 1 had parathyroid carcinoma. All patients had biochemical confirmation of hyperparathyroidism. RESULTS: Twenty-six (58%) of 45 scans accurately predicted the location(s) of all abnormal gland(s) involved (true positive). Surgical removal of these glands was curative. Sixteen (36%) of 45 scans were false negative because they did not show all abnormal glands involved; however, 7 of these 16 scans did localize at least one abnormal gland. The overall sensitivity of this test was 62% when all abnormal glands were considered but increased to 79% with the demonstration of at least one abnormal gland. These values increased to 80% and 90% (p = 0.03), respectively, in the last 20 patients when the injected dose of Tc-99m-sestamibi was increased from 10 to 15 mCi. Thirty-seven of 44 patients were cured after operation. Six of the seven patients who experienced surgical failure had multigland disease, one of which was malignant. Sestamibi scans correctly identified abnormal cervical glands in 18 (58%) of 31 patients and abnormal mediastinal glands in six (75%) of eight patients. CONCLUSIONS: Tc-99m-sestamibi scanning is helpful in the reoperative setting as an adjunct to localizing abnormal parathyroid tissue. A higher percentage of positive tests occurs in patients with mediastinal and single gland disease. A higher dose of Tc-99m-sestamibi (15 mCi) significantly improves test sensitivity.

Adult↗

PubMed2004

Oxyphil parathyroid adenoma: a malignant presentation of a benign disease.

Functioning parathyroid adenomas of the oxyphil cell type are rare, and the clinical characteristics of patients with these tumors have not been well defined. We describe two cases of severe primary hyperparathyroidism (PHPT) caused by benign oxyphil parathyroid adenomas. The patients' clinical presentations mimicked parathyroid carcinoma. Both had very large tumors associated with marked elevations in PTH and serum calcium levels. Skeletal manifestations were also atypical for benign PHPT, with severe osteoporosis in one patient and osteitis fibrosa cystica in the other. These cases also highlight the remarkable capacity of the skeleton to recover after successful parathyroidectomy, previously reported in other forms of severe PHPT. Bone mineral density improved dramatically 1 yr after parathyroidectomy, with increases of 51% at the lumbar spine, 36% at the total hip, and 11% at the distal one third radius. Most of the increases occurred in the first postoperative months. Consistent with this early and accelerated skeletal response, markers of bone turnover were increased 2 months after surgery and normalized by 8 months postoperatively. In patients with PHPT who present with severe or atypical clinical features, oxyphil adenoma should be considered.

Adenoma, Oxyphilic↗

PubMed1993

Passive immunization with anti-parathyroid hormone-related protein monoclonal antibody markedly prolongs survival time of hypercalcemic nude mice bearing transplanted human PTHrP-producing tumors.

Malignancy-associated hypercalcemia is mainly caused by excessive production of parathyroid hormone-related protein (PTHrP) by the tumor. Using anti-PTHrP-(1-34) monoclonal murine antibody (anti-PTHrP MoAb), we studied whether repeated injection of the homologous antibody would continuously decrease the serum calcium concentration in hypercalcemic nude mice bearing transplanted human PTHrP-producing tumors, leading to prolongation of their survival time. Daily SC injections of anti-PTHrP MoAb decreased the serum calcium concentration almost to within the normal range in nude mice bearing transplanted human PTHrP-producing tumors (T3M-1, EC-GI, PC-3, and FA-6) but not in a nude mouse bearing a transplanted parathyroid carcinoma. The antibody did not affect FA-6 tumor growth either in vitro or in vivo. Pancreatic carcinoma cells (FA-6), which caused the most severe hypercalcemia, were inoculated into 6-week-old nude mice. When severe hypercalcemia (approximately 19 mg/dl) had developed, daily SC injection of anti-PTHrP MoAb was started. Within 18 days of this time point, all untreated tumor-bearing mice (n = 10) died of hypercalcemia and cachexia, whereas all the treated mice (n = 10) showed an increase in body weight and survived for at least 25 days. Histologic examination of the treated mice revealed a marked decrease in osteoclastic bone resorption, without toxicologic findings in the kidney and liver. These results suggest that passive immunization against PTHrP can continuously ameliorate the hypercalcemia and markedly prolong the survival time of severely hypercalcemic, tumor-bearing mice. If a human monoclonal antibody against PTHrP-(1-34) could be developed, then passive immunization would be potentially one of the most effective therapies for patients with malignancy-associated hypercalcemia due to excessive production of PTHrP.

Animals↗

PubMed2006

Unexpected serum parathyroid hormone profiles in some patients with primary hyperparathyroidism.

BACKGROUND: Third-generation parathyroid hormone (PTH) assays have been reported to measure only intact PTH(1-84), in contrast to second-generation assays, which also detect PTH(7-84) fragments. Higher PTH measurements were observed with third- than with second-generation PTH assays in a few patients with either severe primary hyperparathyroidism or parathyroid carcinoma. METHODS: We analyzed biological data [second- and third-generation PTH assays, 25-hydroxyvitamin D (25-OHD), calcium, and phosphate concentrations] obtained before and after surgery for 2 groups of patients selected from a large series of consecutive patients with primary hyperparathyroidism (PHPT): 7 female patients with surgically and histologically confirmed PHPT (group 1) and a matched group (group 2). RESULTS: For group 1 but not group 2, PTH concentrations measured by third-generation PTH assays before surgery were higher than those measured by the second-generation assays. Circulating 25-OHD, calcium, and phosphate concentrations were similar in both groups. In addition, PTH values measured with the third-generation PTH assays in group 1 decreased after surgery. CONCLUSIONS: Our results confirm that third-generation PTH assays do not measure only PTH(1-84). The frequency of this unexpected finding of markedly lower PTH concentrations than previously reported was approximately 5% in patients with PHPT without malignancy. We do not know whether the presence of this unexpected profile is predictive of malignancy.

Adult↗

PubMed1992

Pulsatile activation of the hypothalamic-pituitary-adrenal axis during major surgery.

To examine the response of the hypothalamic-pituitary-adrenal (HPA) axis to severe surgical stress, we measured the immunoreactive plasma levels of corticotropin-releasing hormone (CRH), corticotropin, cortisol, arginine-vasopressin (AVP), atrial natriuretic factor (ANF), neuropeptide Y (NPY), interleukin-1 (IL-1), IL-6, interferon gamma (INF), and tumor necrosis factor-alpha (TNF-alpha) in eight patients with Zollinger-Ellison syndrome (ZES) or mediastinal parathyroid carcinoma, all undergoing major surgery with a standardized anesthetic technique. Blood samples were drawn the morning before surgery, every 10 to 30 minutes throughout surgery (average, 308.7 +/- 15 minutes), and every morning for the next 4 postoperative days (POD). During surgery, plasma CRH concentrations were slightly but not significantly elevated compared with those before surgery and with those of the next 4 POD. However, the values were within the normal range (less than 2.2 pmol/L) and showed 8.9 +/- 0.6 pulses (one pulse every 34.7 +/- 1.6 minutes). Plasma corticotropin, on the other hand, was quite elevated, but was also released in a pulsatile fashion during the surgical procedure (one pulse every 36.7 +/- 1.6 minutes). Most of these secretory episodes of corticotropin were temporally related to those of CRH. Corticotropin returned to basal levels on the first POD and remained so for all 4 POD. Plasma cortisol concentrations increased steadily during surgery and remained elevated the first POD. Cortisol showed 6.2 +/- 1.1 pulses during the operative sampling period (one pulse every 71.8 +/- 13 minutes). Plasma AVP concentrations were also markedly elevated during surgery, but individual secretory pulses were not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

Cytokines↗

PubMedDate not supplied

Parathyroid cancer: etiology, clinical presentation and treatment.

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.

Humans↗

PubMed2006

Minimally invasive parathyroidectomy using cervical block: reasons for conversion to general anesthesia.

HYPOTHESIS: We investigated the frequency and reasons for conversion from cervical block anesthesia to general anesthesia (GA) in patients undergoing minimally invasive parathyroidectomy for primary hyperparathyroidism. DESIGN: Prospective case series. SETTING: Tertiary university hospital. PATIENTS: A total of 441 consecutive patients with primary hyperparathyroidism undergoing minimally invasive parathyroidectomy under cervical block and monitored anesthesia care using midazolam and narcotics were included. Patients with known multiglandular, familial, or secondary hyperparathyroidism or noninformative preoperative localization or those electing minimally invasive parathyroidectomy under GA were excluded. INTERVENTION: All patients underwent cervical block anesthesia and focused exploration using minimally invasive techniques. MAIN OUTCOME MEASURE: Intraoperative need for conversion from cervical block anesthesia to general endotracheal anesthesia. RESULTS: Of the 441 patients, 47 (10.6%) required conversion to GA. In all instances, conversion was performed in a controlled fashion using neuromuscular blockade, endotracheal intubation, and maintenance of the original surgical field preparation. Sixteen procedures were converted to accomplish simultaneous thyroid resections. An additional 15 were converted because the intraoperative parathyroid hormone level failed to decrease by at least 50% from the baseline after resection of the incident parathyroid tumor and extensive exploration was required. Eight procedures were converted because of technical difficulties related to ensuring adequate protection of the recurrent laryngeal nerve. Five procedures were converted to optimize patient comfort, and 2 were converted because of the intraoperative recognition of parathyroid carcinoma. One patient experienced a toxic reaction to lidocaine, causing a seizure. CONCLUSIONS: The vast majority of minimally invasive parathyroidectomies can be performed using cervical block anesthesia. However, conversion to GA is appropriate when unexpected intraoperative findings are encountered or for patient comfort.

Anesthesia, General↗

PubMedDate not supplied

Surgical treatment of primary hyperparathyroidism: an institutional perspective.

Three hundred and eighty-four consecutive patients with primary hyperparathyroidism (HPT) were surgically treated at a single institution during the 2 year period 1983 through 1984. Two patients were found to have benign familial hypocalciuric hypercalcemia and a single patient had parathyroid carcinoma. In the remaining 379 patients, the cure rate was 99.5%, the operative mortality 0.3%, persistent vocal cord paralysis 0.8%, and permanent hypocalcemia 0.3%. This data supports a liberal policy regarding cervical exploration in patients with HPT and questions any policy of observation without surgical intervention.

Adolescent↗

PubMed2006

Parafibromin is a nuclear protein with a functional monopartite nuclear localization signal.

Parafibromin is a nuclear protein with a tumour suppressor role in the development of non-hereditary and hereditary parathyroid carcinomas, and the hyperparathyroidism-jaw tumour (HPT-JT) syndrome, which is associated with renal and uterine tumours. Nuclear localization signal(s), (NLS(s)), of the 61 kDa parafibromin remain to be defined. Utilization of computer-prediction programmes, identified five NLSs (three bipartite (BP) and two monopartite (MP)). To investigate their functionality, wild-type (WT) and mutant parafibromin constructs tagged with enhanced green fluorescent protein or cMyc were transiently expressed in COS-7 cells, or human embryonic kidney 293 (HEK293) cells, and their subcellular locations determined by confocal fluorescence microscopy. Western blot analyses of nuclear and cytoplasmic fractions from the transfected cells were also performed. WT parafibromin localized to the nucleus and deletions or mutations of the three predicted BP and one of the predicted MP NLSs did not affect this localization. In contrast, deletions or mutations of a MP NLS, at residues 136-139, resulted in loss of nuclear localization. Furthermore, the critical basic residues, KKXR, of this MP NLS were found to be evolutionarily conserved, and over 60% of all parafibromin mutations lead to a loss of this NLS. Thus, an important functional domain of parafibromin, consisting of an evolutionarily conserved MP NLS, has been identified.

Amino Acid Sequence↗

PubMedDate not supplied

Efficacy of preoperative dual-phase sestamibi scanning in hyperparathyroidism.

PURPOSE: The objective of this article is to evaluate our experience with sestamibi scanning in patients with primary and secondary hyperparathyroidism. PATIENTS AND METHODS: A retrospective review of patients referred to the radiology department at the University of Kansas Medical Center for parathyroid studies between January 1, 1993, and August 1, 1998, was done. Patients included in the study were those who underwent both dual-phase technetium (Tc-99m) sestamibi scanning and subsequent parathyroidectomy at our institution (n = 34). Twenty-six patients had primary hyperparathyroidism and 8 patients had secondary hyperparathyroidism. Fifteen had previous history of neck exploration. RESULTS: Sensitivity of sestamibi scans in detection of all abnormal pathology in cases of primary hyperparathyroidism was 60% overall. Among the subset of adenoma cases, sensitivity was 82% (14/17). Among cases of primary parathyroid hyperplasia, no scan correctly localized all abnormal glands; however 60% (3/5) showed localization of at least one hyperplastic gland. Of the 2 patients with parathyroid carcinoma, in only one case was there evidence of sestamibi retention in the correct thyroid lobe. In patients with secondary hyperparathyroidism, sestamibi scanning was successful in identifying all hyperplastic tissue in only one case (sensitivity 13%). In 7 of the 8 cases of secondary hyperparathyroidism, the scan localized at least one hyperplastic gland. CONCLUSION: Sestamibi scanning is useful in the localization of abnormal pathology in cases of primary hyperparathyroidism, especially adenomas. In cases of hyperplasia, whether attributable to primary or secondary hyperparathyroidism, sestamibi imaging is less successful.

Adult↗

PubMed1992

Gallium nitrate.

OBJECTIVE: To evaluate the therapeutic role of gallium nitrate in the treatment of hypercalcemia associated with malignancy and related disease states. DATA SOURCES: A literature search of English-language studies involving gallium nitrate for the period 1966-1991 using MEDLINE and the bibliographies of relevant articles. STUDY SELECTION: Because of the limited number of studies, all clinical trials were reviewed, with particular emphasis on Phase III comparative trials. Related investigative studies on the pharmacology, pharmacokinetics, and toxicity of gallium nitrate were also reviewed. DATA EXTRACTION: Two appraisers independently abstracted data from available clinical trials and evaluated trial quality. RESULTS OF DATA SYNTHESIS: Two Phase III comparative trials evaluating gallium nitrate in the treatment of hypercalcemia of malignancy have been completed. Gallium nitrate was shown to be superior to both calcitonin and etidronate disodium, based on the comparative percentage of patients achieving normocalcemia and the subsequent duration of normocalcemia. Both trials employed similar methodology. Positive therapeutic effects of gallium nitrate have also been demonstrated in small, noncomparative trials for hypercalcemia associated with parathyroid carcinoma, Paget's disease of bone, and osteolytic bone metastases. CONCLUSIONS: Gallium nitrate is effective in the treatment of hypercalcemia associated with malignancy and is appropriate for formulary addition. In certain clinical situations, it may be clearly advantageous over such agents as calcitonin, plicamycin, and etidronate. Further investigation is needed to define the limitations of nephrotoxicity and the therapeutic potential for other indications. Further comparative clinical trials of gallium nitrate versus bisphosphonates and plicamycin could also help define its relative clinical benefit.

Gallium↗

PubMedDate not supplied

Recurrent acute primary hyperparathyroidism in an adult male patient.

OBJECTIVE: To report the occurrence of recurrent acute primary hyperparathyroidism (HPT), a rare disorder that occurs in only 1 to 2% of patients with primary HPT. METHODS: We describe a patient who had two separate episodes of acute primary HPT and discuss the appropriate treatment of parathyroid crisis. RESULTS: In 1990, primary HPT developed in a 41-year-old man, who underwent surgical removal of a parathyroid adenoma. He remained normocalcemic until 1995, when acute primary HPT developed after lithium therapy was initiated because of depression. Calcium and parathyroid hormone (PTH) levels declined after lithium therapy was discontinued, but they remained slightly above the normal range. Nine months later, he was rehospitalized with acute primary HPT. After stabilization, a second parathyroid adenoma was successfully resected, and calcium and PTH levels subsequently remained normal. In this disorder, levels of PTH are increased up to 20 times normal, and the clinical manifestations are similar to parathyroid carcinoma. Treatment involves rehydration, antiresorptive agents, and parathyroidectomy. Our patient initially was thought to have lithium-induced primary HPT, which can occur in up to 10% of patients on long-term lithium therapy. The mechanism is unknown but may be an alteration of the calcium-PTH "set-point." CONCLUSION: Patients with asymptomatic primary HPT should have close follow-up because of the risk of development of acute primary HPT. Patients at risk, such as those with immobilization or severe illness, should be identified. Drugs known to interfere with calcium metabolism (for example, lithium) should be avoided in patients with primary HPT.

Journal Article↗

PubMedDate not supplied

Primary hyperparathyroidism: diagnosis and management.

OBJECTIVE: To review the manifestations of primary hyperparathyroidism and the available treatment strategies. METHODS: The epidemiologic and pathologic features of this endocrine disorder are outlined. Guidelines for surgical intervention are discussed, and the effectiveness of various medical treatments is summarized. RESULTS: Primary hyperparathyroidism, a common disorder, is diagnosed on the basis of hypercalcemia in the presence of increased parathyroid hormone levels as measured by immunoassay. Clinical manifestations are variable with many patients being asymptomatic at the time of diagnosis. Patients with severe disease require definitive surgical treatment. Surgical cure rates are high--approximately 95% in experienced hands. Indications for surgery include a serum calcium of more than 2.9 mmol/L (12 mg/dL), osteoporosis, recurrent renal stones, and parathyroid carcinoma. As well, it is recommend in individuals younger than 50 years of age. Patients with mild disease may have a benign natural history and may not have progression to severe disease. Asymptomatic individuals with mild hypercalcemia and close to normal bone mass and renal function may be managed medically, particularly those who are over the age of 50 years. Medical management includes ensuring adequate hydration and avoiding volume depletion. Estrogen therapy is valuable in postmenopausal women without contraindications to hormone replacement. Calcitonin has been shown to decrease serum calcium levels on a short-term basis. Bisphosphonates are also potential treatment options and require further study. Calcium-mimetic agents also may become valuable in the medical management of primary hyperparathyroidism in the near future. CONCLUSION: As primary hyperparathyroidism is being increasingly detected at an asymptomatic stage, medical therapy is assuming a greater role in the effective management of this common condition.

Journal Article↗