Functioning oxyphil cell adenomas of the parathyroid gland. A study of 15 cases

Parathyroid adenomas composed predominantly of chief cells are the most frequent cause of primary hyperparathyroidism. Until as recently as 1978, the rare oxyphil cell parathyroid adenoma was generally considered nonfunctioning. A retrospective review of 500 consecutive patients at the Massachusetts General Hospital with a diagnosis of hyperparathyroidism associated with parathyroid adenoma during the years 1979-1987 yielded 15 (3.0%) oxyphil cell adenomas. A total of 65 case reports of hyperparathyroidism associated with a diagnosis of oxyphil cell adenomas were reviewed, applying the same diagnostic criteria used in case selection for the present series. These criteria include: (a) at least 90% composition of the adenoma by oxyphil cells; (b) biopsy or excision of a second histologically normal parathyroid gland to help rule out hyperplasia; and (c) postoperative alleviation of hypercalcemia. More than 50% of the previously reported cases did not conform to these criteria. The findings in the present study further document the entity of hyperparathyroidism caused by oxyphil cell parathyroid adenomas and suggest criteria guidelines for this rare diagnosis.     

Localization of parathyroid adenomas by computer-assisted parathyroid scanning.

In an attempt to localize adenomas of the parathyroid glands 36 patients with suspected hyperparathyroidism were studied with a computer-assisted double isotope scanning technique. Six patients were excluded from the statistical analysis because of uninterpretable scans. A definite localization was made with the computer-assisted scan in 16 patients. In 14 of these patients the site of the tumours was correctly predicted. In 14 patients no localization was seen on the scan. Four of these patients were classified as false negatives. In 14 out of the 16 correctly localized tumours two-thirds had weights equal to or less than 1-5 g.     

Mediastinal parathyroid adenomas. A cause of persistent hyperparathyroidism

Unrecognized mediastinal parathyroid adenomas that are inaccessible via a standard cervical exploration are an important cause of persistent primary hyperparathyroidism. Of 26 patients evaluated at UCLA Medical Center for persistent primary hyperparathyroidism, six required sternotomy (5) or thoracotomy (1) for cure of their disease. Analysis of these six patients suggests that aberrant embryologic development is the most logical explanation for the ectopic location of these mediastinal adenomas. In most instances, preoperative localization of the adenoma is possible. Permanent hypoparathyroidism occurs in a significant percentage of patients undergoing reoperative parathyroid surgery. Efforts to minimize postoperative morbidity should include a careful and systematic approach to the preoperative and intraoperative management of patients with mediastinal adenomas, as well as consideration of autotransplantation or cryopreservation of parathyroid tissue.     

Microfluorometric measurements of cytoplasmic calcium in chief and oxyphil parathyroid cells of adenomatous and hyperplastic glands and of normal-sized glands associated with adenomas

The effects of extracellular calcium on the cytoplasmic Ca2+ concentration (Ca2+i) were studied by dual-wavelength microfluorometry in individual human parathyroid cells obtained from adenomatous glands and normal-sized glands associated with adenomas in hypercalcemic hyperparathyroidism (HPT), as well as from enlarged glands of patients with uremia with HPT. In comparison with the normal parathyroid tissue, chief cells of the adenomatous and hyperplastic glands showed significantly lower Ca2+, and also right-shifted responses of Ca2+i to increases in the extracellular calcium concentration within the 0.5 to 3.0 mmol/L range. This pathophysiologic disturbance apparently was independent of the cell size. Oxyphil cells of nodules from the hyperplastic glands had lower Ca2+i and responded less to increments in extracellular Ca2+ than the chief cells from the surrounding parts of the same glands. Also the chief cells from the normal-sized glands associated with single adenomas exhibited a disturbance of the regulation of Ca2+i, which was less pronounced than that in the cells of the adenomas. These findings support the presence of relative calcium insensitivity of Ca2+i in chief and oxyphil parathyroid cells from adenomatous and hyperplastic glands. This derangement may also be found in all parathyroid glands of individuals with adenomatous HPT.     

The blood supply of mediastinal parathyroid adenomas.

Arteriography for parathyroid localization following unsuccessful neck surgery should include selective catheterization of the inferior thyroid and internal mammary arteries bilaterally. When the arterial supply to a mediastinal adenoma arises from the internal mammary artery, recovery from the neck may not be possible and an open mediastinal exploration (or embolization) should be considered.     

A case of functioning parathyroid cyst]

We report a rare case of primary hyperparathyroidism with a functioning parathyroid cyst in a 45-year-old male. He was a recurrent stone former, and consulted our hospital for further examinations of hypercalcemia. Plasma levels of intact parathyroid hormone (PTH) were elevated to 130 pg/ml. Ultrasonography, computed tomography and magnetic resonance imaging revealed a parathyroid cyst on the right lobe of the thyroid gland. We performed right superior parathyroidectomy. Histological examination demonstrated a secondary pseudocyst resulting from cystic degeneration of a parathyroid adenoma. Plasma levels of intact PTH normalized after operation. To our knowledge, only 48 cases of functioning parathyroid cyst were reported in the Japanese literature. We discuss the clinical features and histological evidence of functioning parathyroid cyst.     

Technetium-thallium scintiscanning for localization of parathyroid adenomas and hyperplasia. A reappraisal

The dual tracer nuclear scintiscan using technetium and thallium to localize enlarged or ectopic parathyroid tissue has been reported to be highly accurate and efficacious. Fourteen previous series reporting results of the technique have been compiled from the literature and analyzed. This analysis has revealed a total of 317 surgically confirmed scan results with a low false-positive rate (17 of 317 scans), a sensitivity rate of 82 percent, and an overall accuracy rate of 78 percent. Forty-five patients from five Portland area hospitals have been retrospectively studied. They had a total of 49 preoperative scans. In our experience with the scan, a higher false-positive rate (4 of 45 scans), a sensitivity rate of 78 percent, and an overall accuracy rate of 73 percent were noted. The scan's effectiveness in acknowledged areas of difficulty in parathyroid surgery, such as patients with ectopic adenomas, hyperplastic glands, and those with previous neck explorations, has been analyzed. We conclude that the scan is a useful preoperative localization tool, especially in patients with ectopic adenomas or with persistent hypercalcemia after neck exploration. However, it is less accurate than initially reported in complex patients, and additional localization techniques are frequently required.     

Color Doppler sonography in the detection of parathyroid adenomas.

BACKGROUND: Various diagnostic modalities have been utilized to aid in the detection of abnormal parathyroid tissue; however, its localization is not always easy. The purpose of this study was to determine whether the evaluation of potential hemodynamic changes in thyroid arteries could aid in the detection of parathyroid adenomas. METHODS: Twenty-eight patients with laboratory evidence of hyperparathyroidism were examined with color Doppler sonography. Data were collected for the superior and inferior thyroid arteries separately. These findings were compared with data for a control group of 14 healthy subjects. RESULTS: Retrospective analysis of the data indicated that peak systolic velocities in the inferior thyroid arteries ipsilateral with the parathyroid adenomas were significantly higher than in normal controls (p <.001). Peak velocity values in the superior thyroid arteries ipsilateral with parathyroid adenomas located in the upper position were also significantly increased compared with those in control subjects (p <. 02). Conversely, peak velocities in the inferior and superior thyroid arteries contralateral with the adenomas, as well as velocities in the superior thyroid arteries ipsilateral with lower position adenomas, did not differ significantly from those in control subjects. The localization of both side and level site of the adenomas presented an accuracy of 86.6%, sensitivity reached 96. 5%, and specificity 83.1%. CONCLUSION: Our results suggest that color Doppler sonography can be used to improve diagnostic accuracy in detecting parathyroid adenomas.     

散发性甲状旁腺腺瘤基因改变的研究进展

散发性甲状旁腺腺瘤是引起原发性甲状旁腺功能亢进的重要原因.但甲状旁腺腺瘤发病机制不清且缺乏早期特异性诊断指标.近年来随着分子生物学的发展,甲状旁腺腺瘤在基因水平的研究取得了很大的进展.本文就其在分子生物学的改变做一综述.     

Ultrasonography in the localization of parathyroid adenomas

The use of ultrasonography in the diagnosis of a parathyroid adenoma is described, and the limitations and advantages of this method are discussed.     

Localization of parathyroid adenomas by digital subtraction angiography. A report of 4 cases

Intravenous digital subtraction angiography provides an accurate but not specific method for localization of small vascular tumours. It is carried out on outpatients as an intravenous procedure and takes only 40 minutes. It appears to be eminently suited to the demonstration of parathyroid adenomas and shows that a hyperplastic parathyroid gland can produce a significant enough vascular blush to create a visible image.     

The role of hyperplasia in multiple parathyroid adenomas

BACKGROUND: Parathyroid adenoma is the most common cause of primary hyperparathyroidism (pHPT). Adenomas usually involve only a single gland, and the remaining glands are normal or suppressed. Multiple parathyroid adenomas have been reported to occur in as high as 11% of patients with pHPT. The significant incidence of multiple adenomas with histologic similarities to hyperplasia has raised the possibility that adenoma is a continuation of the hyperplasia state. To test this theory, we used molecular genetics to compare clonality and proliferative activity of parathyroid adenoma with its corresponding normal glandular tissue. Furthermore, we devised a scheme to definitively distinguish between the different parathyroid states on a molecular level, because histologic distinction is unreliable. METHODS: The study included three patients with a diagnosis of singular parathyroid adenoma and three with double parathyroid adenomas. Paraffin-embedded surgical specimens of both adenomas and normal glands were retrieved from each patient. Clonal analysis of the phosphoglycerolkinase (PGK) gene has suggested that parathyroid adenomas are monoclonal. Clonality of parathyroid adenomas and normal parathyroid glands was studied by polymerase chain reaction-based restriction fragment length polymorphic analysis for the PGK gene. Proliferative activity of the specimens was also analyzed using the immunohistochemical markers PCNA and Ki-67. RESULTS: All adenomas were monoclonal and all normal parathyroid glands were polyclonal for the PGK gene in both the single and double adenoma specimens. All adenomas stained positive for proliferative activity. In the three patients with singular adenoma, proliferative activity was not detected in the normal parathyroid tissue. However, in the double adenoma group, two of the three patients showed hyperproliferative activity in the normal glands. CONCLUSION: Proliferative activity consistent with hyperplasia was present in some normal glands of multiple adenoma patients. Our observation supports the theory that multiple adenomas may be a continuation of the hyperplasia state.     

Radioguided tumorectomy in the management of parathyroid adenomas

HYPOTHESIS: A clearly localizing sestamibi scan predicts a successful minimally invasive radioguided parathyroidectomy that can be performed with a shorter operative time, low morbidity, and decreased duration of hospital stay. DESIGN: Review of prospectively gathered data and patient medical records. SETTING: Hospitalized care.Patients and METHODS: Parathyroidectomy was performed on 55 patients with a secure biochemical diagnosis of hyperparathyroidism and a sestamibi scan performed at the University of Connecticut Health Center. Of the 40 patients with a clearly positive sestamibi scan result, 31 underwent radioguided parathyroidectomy. The results of radioguided parathyroidectomy are compared with those of the standard bilateral exploration performed in the remaining 24 patients. MAIN OUTCOME MEASURES: Ionized calcium concentration, postoperative complications, and operative time. RESULTS: All patients were cured of hyperparathyroidism, and no patients experienced recurrent laryngeal nerve damage. Parathyroid adenomas were found at the predicted site in all 40 patients with a clearly localizing sestamibi scan. Of the 31 patients who underwent radioguided parathyroidectomy, a single parathyroid adenoma was identified in 30 patients, and a double adenoma was found in 1 patient. Conversion to a standard procedure was necessary in 1 patient with a large adenoma. The average operating room time was 128 minutes for the radioguided procedure and 224 minutes for the standard exploration. The average incision length for radioguided parathyroidectomy was 3.3 +/- 0.7 cm. CONCLUSIONS: A clearly localizing sestamibi scan predicts that 97% of patients can undergo a successful and safe minimally invasive radioguided parathyroidectomy that requires less operative time than the standard exploration.     

Multiple gastric polyps and parathyroid adenomas. Report of two cases.

Two cases of multiple gastric polyps associated with parathyroid adenomas are presented. A review of the literature revealed four patients with multiple gastric polyps and multiple endocrine adenomatosis. The possiblity of multiple gastric polyps as a variant of the MEA syndrome complex is explored. Emphasis is placed on the need for thorough endocrine evaluation in patients with multiple gastric polyps.     

Intraoperative parathyroid hormone monitoring fails to detect double parathyroid adenomas: a 2-institution experience.

BACKGROUND: We hypothesized that intraoperative parathyroid hormone monitoring (IOPTH) reliably would detect double parathyroid adenomas. METHODS: This was a retrospective study of 20 patients undergoing conventional parathyroidectomy with resection of exactly 2 abnormal glands. Full exploration was performed regardless of IOPTH values, which were measured after anesthetic induction and 5 and 10 minutes following removal of the first abnormal parathyroid gland. Failure to fall below 50% of baseline value by 10 minutes following resection of the first gland indicated the presence of multiglandular disease. RESULTS: All patients were cured. All excised glands were hypercellular on histology. Mean IOPTH values in 9 of the 20 patients with true negative results (noncurative decrease, another gland present) were 66% +/- 7% at 5 minutes and 83% +/- 15% at 10 minutes. The IOPTH values in 11 of the 20 patients with false positive results (curative decrease, another gland present) were 28% +/- 4% at 5 minutes and 18% +/- 2% at 10 minutes. The false positive rate of IOPTH was 55%. CONCLUSIONS: We found that IOPTH failed to reliably detect the presence of double parathyroid adenomas. These data suggest that caution should be exercised when terminating limited parathyroid exploration based on a curative fall in IOPTH values.