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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three cases of palpable cystic parathyroid nodules examined by fine needle aspiration (FNA) cytology are reported. Two of the three aspirates were incorrectly identified as thyroid neoplasms due to the presence of papillary clusters or microfollicles and grossly golden-brown cyst fluid. Histologic examination of these two nodules revealed partially cystic parathyroid adenomas. Aspirated material from the third patient yielded clear watery fluid, which was correctly identified as consistent with a parathyroid cyst. The diagnostic difficulties in the differentiation of parathyroid adenoma from thyroid carcinoma or adenoma are discussed, as is the utilization of assays for parathyroid hormone in making the FNA diagnosis of parathyroid lesions.
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PMID:Fine needle aspiration cytology of cystic parathyroid lesions. A cytomorphologic overlap with cystic lesions of the thyroid. 192 81

A significant number of patients with primary hyperparathyroidism have negative preoperative 201Tl/99Tcm subtraction localization scans. In this study an attempt was made to improve scan localization by creating a period of relative hypocalcaemia and increased parathyroid hormone (PTH) secretion before scanning. Six patients with primary hyperparathyroidism were studied (mean serum calcium 2.80 mmol l-1; range 2.70-2.95). All had had a negative standard 201Tl/99Tcm scan carried out within the 6 months prior to this study. Patients were commenced on an intravenous infusion of the calcium chelating agent trisodium edetate at a dose of 24 mg kg-1 h-1 given in 500 ml 0.9% saline over 90 min. Immediately thereafter a 201Tl/99Tcm scan was carried out in the usual way. Three patients showed areas of discordant thallium uptake consistent with the presence of a parathyroid adenoma. Two of these patients had surgery and an adenoma was found at the site corresponding to the scan appearances. It would appear that creating relative hypocalcaemia and increasing PTH secretion may allow increased thallium uptake, possibly secondary to the increased cellular metabolic activity, and thus creating a positive scan.
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PMID:Augmentation of parathyroid 201Tl/99Tcm scanning by infusion of trisodium edetate. 194 90

We have described 4 patients with chronic renal failure receiving regular haemodialysis treatment who underwent total parathyroidectomy with autotransplantation of parathyroid fragments into the forearm musculature for hypercalcaemic hyperparathyroidism. In all, there was an immediate and profound fall in plasma calcium levels. Hypercalcaemia recurred 1-5 years post-operatively and was resistant to resection of the autograft. In 3 cases, thallium-technetium subtraction scanning and multiple venous sampling for estimation of parathyroid hormone levels suggested multiple sites of hypersecretion of parathyroid hormone in the neck. In 1 case, these investigations revealed a mediastinal adenoma which was successfully removed. These cases reinforce previous suggestions that total parathyroidectomy is frequently incomplete and undermine the procedure of total parathyroidectomy with autotransplantation in patients with persisting uraemia.
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PMID:Pitfalls after total parathyroidectomy and parathyroid autotransplantation in chronic renal failure. 196 65

Between 1982 and 1989, 145 patients underwent operations for persistent or recurrent primary hyperparathyroidism (HPT). At re-exploration, 15 patients (10.3%) were found to have locally recurrent parathyroid tumors (11 patients with adenoma and 4 with carcinoma). These 15 patients had 28 previous operations at outside institutions for HPT. Patients with locally recurrent HPT secondary to adenoma had a longer disease-free interval than patients with locally recurrent carcinoma. At the time of evaluation at the National Institutes of Health (NIH) for recurrent or persistent HPT, each patient was symptomatic and patients with carcinoma had significantly more symptoms and higher serum levels of calcium and parathyroid hormone than patients with adenoma. Locally recurrent parathyroid neoplasm was correctly localized by preoperative testing in 14 of 15 patients. These 15 patients underwent 18 reoperations at NIH for excision of locally recurrent parathyroid tumors. Following the final reoperation (two patients had more than one procedure), each patient had normal serum levels of calcium. In addition each patient remains biochemically cured (based on normal serum calcium level), with a median follow-up interval of 21 months. Local recurrence of parathyroid adenoma comprises a small but significant proportion of cases of recurrent or persistent HPT and can be indistinguishable from parathyroid carcinoma. Findings suggestive of carcinoma include shorter disease-free interval, higher serum levels of calcium and parathyroid hormone, and histologic appearance. Whether the locally recurrent parathyroid neoplasm is benign or malignant, aggressive surgery can control serum levels of calcium in these patients with acceptable rates of morbidity.
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PMID:Locally recurrent parathyroid neoplasms as a cause for recurrent and persistent primary hyperparathyroidism. 198 39

We report the detailed molecular characterization of a human parathyroid adenoma with a clonal parathyroid hormone gene rearrangement. This rearrangement is similar to one we characterized recently in an independent adenoma. In these two, plus a third partially characterized adenoma, one allele of the PTH gene, on 11p15, is rearranged with DNA from the D11S287 region on 11q13. This region contains a transcribed sequence, D11S287E, distinct from known 11q13 oncogenes, that is expressed in all parathyroid tissues examined, but is overexpressed dramatically in all three tumours with PTH gene-D11S287 rearrangements. These findings suggest that overexpression of D11S287E, perhaps driven by the misplaced PTH gene's regulatory elements, contributed to the development of these benign tumors. D11S287E is a new candidate oncogene with potential importance in parathyroid adenomas and perhaps other tumors with 11q13 abnormalities.
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PMID:Rearrangement and overexpression of D11S287E, a candidate oncogene on chromosome 11q13 in benign parathyroid tumors. 201

Routinely processed parathyroid tissues from 26 cases with primary hyperparathyroidism (19 adenomas, 7 multiglandular hyperplasia) and 8 normal human parathyroid glands were investigated with antibodies against chromogranin A and B and parathyroid hormone (PTH). Normal parathyroids were immunohistochemically positive for PTH and chromogranin A but negative for chromogranin B. Hyperplastic glands showed a focal staining for PTH and chromogranin A without correlation of the staining pattern on serial sections. Adenomas were either uniformly positive for both PTH and chromogranin A or showed a staining pattern similar to that seen in hyperplastic glands. Focal chromogranin B positivity (less than 10% of cells) was found in 3 cases (1 hyperplastic gland and 2 cases of parathyroid adenoma with an immunohistochemical staining pattern similar to hyperplastic glands). Our immunohistochemical results may support previously published findings that most parathyroid adenomas are monoclonal neoplasms whereas hyperplastic glands are of polyclonal origin.
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PMID:Chromogranin A and B in parathyroid tissue of cases of primary hyperparathyroidism: an immunohistochemical study. 202 50

Primary hyperparathyroidism is a quite frequent disease, the incidence of which has been found to increase over the past two decades. At the same time there has been a remarkable change in its clinical presentation; therefore this endocrine disorder earlier considered rare but almost always associated with complications, now appears a quite common and uncomplicated disease. In our series of 150 patients diagnosed between 1966 and 1989 the female/male ratio was found to be 1.77. The ratio has significantly increased (2.09), beginning from 1983; this was mainly due to the availability of a bone densitometer at our Mineral Metabolism Service with consequent greater demand of serum calcium determination as a part of routine metabolic screening for prevention of postmenopausal osteoporosis. Whilst the percentage of patients with renal manifestations of the disease has not significantly changed during these years, the amount of asymptomatic patients (yrs 1966-1983 = 3.7% vs yrs 1984-1989 = 39.7%) has progressively increased to the detriment of patients with skeletal symptoms. Serum intact parathyroid hormone determination by immunoradiometric assay (and possibly by immunochemiluminometric assay) seems to have overcome some of the methodological problems inherent in conventional radioimmunoassay. Surgical treatment of primary hyperparathyroidism is safe and highly effective in experienced hands. Recurrence has been observed only in three cases after resection of parathyroid adenoma, thus indirectly supporting a monoclonal origin of the tumor. Medical behavior (conservative or surgical management) in respect to patients with the mild or asymptomatic form of the disease, especially when diagnosed in old age, is uncertain at this point in time. Future prospective studies carried out on a large number of patients are needed to better clarify this issue.
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PMID:[Primary hyperparathyroidism: the recent findings]. 207 75

To assess the ability of ultrasonography (US) and dual tracer thallium-technetium subtraction scanning (NS) to localize abnormal parathyroid glands, these two investigations were carried out preoperatively in 27 consecutive patients who underwent surgery for hyperparathyroidism. Nineteen patients had adenomas and 8 hyperplasia. Of 23 US procedures 2 were inadequate, and of 26 NS procedures 1 was inadequate. Ultrasonography was found to be superior to NS for preoperative localization of abnormal parathyroid glands (sensitivity per gland 53% versus 36%); detection rates for hyperplasia were poor for both techniques (sensitivity per gland 36% and 25%). However, when positive, both techniques were extremely accurate (positive predictive value of 100% for both). There was no correlation between the weight of the gland or degree of physiological hyperfunction (parathyroid hormone level) and detection rates for the two techniques. False-positive results were rare for both, so a positive result was highly predictive of an abnormality at that location. Ultrasonography had sufficient accuracy to suggest its routine use when adenoma is suspected, particularly to detect the side of the lesion (sensitivity 78% and positive predictive value 100%). The addition of subtraction scintigraphy does not appear to be warranted.
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PMID:Preoperative parathyroid localization: a prospective evaluation of ultrasonography and thallium-technetium scintigraphy in hyperparathyroidism. 216 4

In 49 patients with primary hyperparathyroidism, intact parathyroid hormone (PTH) was measured with a recently developed immunoradiometric assay, and midregional PTH fragments (sequence 44-68) were measured with an established radioimmunoassay technique. In 47 normal subjects, the concentration of intact PTH ranged from 2.0 to 6.8 pmol/l, and in 49 patients with primary hyperparathyroidism it ranged from 6.4 to 80.0 pmol/l. In contrast, midregional PTH fragments were normal in seven of 49 patients with primary hyperparathyroidism. In five healthy controls and in 12 patients with surgically confirmed primary hyperparathyroidism and serum calcium levels below 3.0 mmol/l, a rapid calcium loading test was performed. In healthy controls, intact PTH was in the low normal to subnormal range within 2.5-5.0 min, and had recovered within 15 min of calcium infusion. In patients with primary hyperparathyroidism, the calcium infusion also led to a 30-50 per cent decrease in intact PTH levels within 5.0-7.5 min after injection, with a slow recovery after 10-15 min. In six of the patients with only slightly elevated basal intact PTH, a suppression to the normal range was observed. In 24 patients (16 patients with a solitary adenoma and eight patients with four-gland hyperplasia) the intact PTH levels were followed intraoperatively during parathyroidectomy, revealing a significantly different rate of decline for single adenomas compared with hyperplasia during the first 15 min after removal of the primary enlarged gland. Intact PTH values remained constantly elevated in one patient with primary hyperparathyroidism and an unsuccessful neck exploration. These results confirm that (a) the measurement of intact PTH in patients with primary hyperparathyroidism is superior to the measurement of midregional fragments; (b) PTH secretion in primary hyperparathyroidism is not totally autonomous; and (c) intraoperative monitoring of intact PTH values could be used to monitor the success of surgery.
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PMID:Intact parathyroid hormone in primary hyperparathyroidism. 231 77

Parathyroid cysts are rare lesions. Pathological examination distinguishes the "true" parathyroid cysts (non functional) most often present and cystic degeneration of a parathyroid adenoma (rare) with clinical or biochemical evidence of hyperparathyroidism. With the increased use of ultrasound and fine needle aspiration biopsies, the diagnosis of these cysts can be confirmed by an elevated parathyroid hormone (PTH) assay. The non-functioning parathyroid cysts can be successfully treated by total aspiration of the cyst fluid. Surgical exploration of all parathyroid glands is the treatment of choice for hyperparathyroidism. The different proposed etiologies for parathyroid cysts are discussed.
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PMID:[Cysts of the parathyroid glands. Apropos of 6 cases]. 234 46


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