Ultrasonographic evaluation of parathyroid hyperplasia in multiple endocrine neoplasia type 1: Positive correlation between parathyroid volume and circulating parathyroid hormone concentration.

There are few reports on parathyroid ultrasonography of multiple endocrine neoplasia type 1 (MEN1). This study investigated the ultrasonographic features of parathyroid glands in 10 patients with MEN1 who underwent preoperative neck ultrasonography and parathyroidectomy between 2006 and 2010 at Toranomon Hospital. We retrospectively analyzed clinical features, laboratory and ultrasonographic data, and pathological diagnosis. A total of 38 parathyroid glands were surgically removed (three to five glands from each patient). All removed parathyroids were pathologically diagnosed as hyperplasia. Seven cases (70.0 %) had adenomatous thyroid nodules. Twenty-five enlarged parathyroid glands (65.8 %) were detected by preoperative ultrasonography with a detection rate of 81.8 % (9/11) and 59.3 % (16/27) for patients without and with adenomatous nodules, respectively. Total parathyroid gland weight and potentially predictable total parathyroid volume by preoperative ultrasonography were significantly correlated with preoperative serum intact parathyroid hormone (iPTH) concentration (R = 0.97, P < 0.001 and R = 0.96, P < 0.001, respectively). The equation used for prediction of the total volume by ultrasonography was 15 × iPTH (pg/ml) - 1,000 and that for total weight was 20 × iPTH (pg/ml) - 1,400. Although adenomatous nodules often coexisted with MEN1 and made identification of enlarged parathyroid glands by ultrasonography difficult, the positive correlation between the predictable parathyroid volume by ultrasonography and serum iPTH suggests that their measurement is useful in the preoperative detection and localization of enlarged parathyroid glands in patients with MEN1. Furthermore, the presence of parathyroid glands that should be resected can be predicted before surgery using the equation proposed here.

Rosuvastatin induces apoptosis in cultured human papillary thyroid cancer cells.

Statins show antiproliferative activity in various cancer cells. The aim of this study was to evaluate the effects of rosuvastatin treatment on papillary thyroid carcinoma. The papillary thyroid carcinoma (B-CPAP) and normal (Nthy-ori 3-1) thyroid cell lines were treated with rosuvastatin at 12.5, 18.5, 25, 50, 100, and 200 µM concentrations. After 48 and 72 h of rosuvastatin treatment, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, Ki-67 immunolabeling, FACS analysis, electron microscopy, caspase-3, and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) analysis were performed. Decreased cell viability and G1 phase arrest were detected in papillary thyroid cell line treated with rosuvastatin. Positive immunoreactivity of Ki-67 and dose-dependent increase in S phase on Nthy-ori 3-1 cells were also detected. B-CPAP cells showed intense vacuolisation and autophagosomes with low concentrations and 48 h incubations, while Nthy-ori 3-1 cells showed these changes at higher concentrations. A decrease in the percentage of cells showing autophagy was determined with increasing concentrations of rosuvastatin in B-CPAP cells. Rosuvastatin treatment also caused a dose- and time-dependent increase in caspase-3 activity and apoptotic index by TUNEL assay in B-CPAP cells compared with the Nthy-ori 3-1 cells. Apoptotic cells with nuclear condensation and fragmentation were observed in B-CPAP cell line. Rosuvastatin induced autophagic changes in B-CPAP papillary thyroid cancer cells in lower doses and caused a shift from autophagy to apoptosis. Rosuvastatin may be an alternative treatment for refractory papillary thyroid cancer. Further in vivo studies are necessary to clarify the effects of rosuvastatin in papillary thyroid carcinoma and the clinical implications of rosuvastatin treatment.

Lateral minimal parathyroidectomy: safety and cosmetic benefits.

BACKGROUND: Surgery has been the cornerstone of treatment for primary hyperparathyroidism for almost three decades. The recent application of state-of-the art imaging technologies to localize hyperfunctioning adenomas preoperatively has enabled surgeons to minimize the surgical procedure, reduce total operation time and improve cosmetic results without compromising the cure rate. STUDY DESIGN: Twenty-one patients with a diagnosis of primary hyperparathyroidism were selected for treatment with the lateral minimal parathyroidectomy approach following preoperative imaging with ultrasonography, Tc-sestamibi scan, or both. All patients were followed during hospitalization and for three months after for calcium levels and cosmetic results. RESULTS: The procedure was performed by the same surgical team for all 21 patients; under general anesthesia in 20 patients and under deep sedation in 1 patient at high surgical risk. In all cases, parathyroid adenoma was accurately localized by at least one of the imaging modalities before surgery: ultrasonography in 16 patients (76%), Tc-sestamibi scan in 15 (71%), and both in 10 (48%). Average total operative time for the lateral minimal invasive approach was 46 minutes (range 30-65 minutes). Blood calcium levels returned to normal in all patients, and cosmetic results were graded good to excellent. CONCLUSIONS: With accurate preoperative localization of unilateral parathyroid adenoma by any imaging modality and careful patient selection, lateral minimal parathyroidectomy performed by a skilled surgeon may serve as a safe, effective procedure with good clinical and aesthetic outcomes.

Three-dimensional cytomorphology in fine needle aspiration biopsy of parathyroid lesions.

OBJECTIVE: To elucidate three-dimensional (3-D) cytomorphology in fine needle aspiration biopsy (FNAB) of parathyroid lesions. STUDY DESIGN: Ultrasound-guided FNAB was performed on parathyroid lesions from 10 patients with hyperparathyroidism. The aspirates were stained and observed under a light microscope (LM). The aspirates were also fixed, dehydrated, critical point dried, spattered with gold ions and observed with a scanning electron microscope (SEM). Findings under SEM were correlated with the appearances under LM as well as with serum parathyroid hormone (PTH) concentrations. RESULTS: Under LM, nine cases displayed isokaryosis and one case, anisokaryosis. These appearances corresponded to isocytosis or anisocytosis under SEM. Under SEM, 3-D cytomorphology of parathyroid lesions displayed isocytotic, scattered cells in five cases, uniform cellular arrangements in four cases and anisocytotic, scattered cells in one case. The cell surface was rather smooth in five cases. The other five cases had significant granules on the cell surfaces; these all had serum PTH concentrations > or = 268 pg/mL. CONCLUSION: 3-D cytomorphology in FNAB of parathyroid lesions was a rather smooth cell surface in cases with low serum PTH and a granular cell surface in cases with significantly increased serum PTH. These characteristics and the absence of microvilli might be helpful in the differential diagnosis between parathyroid and follicular thyroid lesions.

AgNOR quantity as a prognostic tool in hyperplastic and neoplastic parathyroid glands.

Prediction of evolution of secondary hyperplasia and tumours of the parathyroid glands is still a problem in histopathology. To assess whether the quantity of silver-stained nucleolar organiser region (AgNOR) proteins might be used as a prognostic tool in parathyroid pathology, a standardised AgNOR analysis has been performed on 19 cases of parathyroid hyperplasia caused by secondary hyperparathyroidism (PH), 8 cases of adenoma (PA) and 10 cases of carcinoma (PC). Clinico-pathological data and follow-up information were available. On formalin-fixed and paraffin-embedded sections, the visualisation and quantification of AgNORs were achieved according to the 1995 guidelines of the Committee on AgNOR Quantification. Then, the mean area (square micrometres) of AgNORs per nucleus (NORA) was evaluated by means of an image analyser and specific softwares. After testing the normal distribution of NORA values, statistical parametric tests were utilised; Kaplan-Meier and Cox multivariate analyses were also performed. In parathyroid lesions, a progressive increase of mean NORA values was observed from PH (2.895 microm2; SE 0.171) through PA (3.638 microm2; SE 0.125) to PC (4.701 microm2; SE 0.179); these differences were highly significant (P<0.001), although some degree of overlap was found among single NORA values. A significantly higher mean NORA value was revealed in PC with distant metastases than was noted in cases with no current clinical evidence of disease progression. Furthermore, a significantly (P<0.001) higher mean NORA value was encountered in the group of PH with recurrences (3.600 microm2; SE 0.106) than in nonrecurrent PH (2.261 microm2; SE 0.087). Multivariate analyses indicated that the NORA value was an independent prognostic parameter determining the risk of recurrence in PH. We suggest that AgNOR quantity may be a promising additional tool for predicting the biological behaviour of parathyroid lesions.

Intranuclear holes (cytoplasmic pseudoinclusions) in parathyroid neoplasms, or "holes happen".

BACKGROUND: A parathyroid adenoma demonstrating intranuclear holes on aspiration cytology prompted a review of parathyroid neoplasms to determine the frequency of this phenomenon. METHODS: Aspiration cytology slides from 30 parathyroid adenomas and 1 parathyroid carcinoma were reviewed. In addition, histologic slides from 136 parathyroid adenomas and 7 parathyroid carcinomas were reviewed. Twenty-two cases had both cytologic and histologic slides available for review. The presence and approximate frequency of intranuclear holes were recorded. RESULTS: On cytologic smears, intranuclear holes were found in 3 of the 31 cases reviewed (2 adenomas and 1 carcinoma). The holes were frequent in only one adenoma (the index case) and moderate-rare in the other two cases. Review of tissue slides showed holes in 9 of 136 adenomas and 3 of 7 carcinomas; 2 adenomas and 2 carcinomas had frequent holes, whereas the remainder had holes infrequently. CONCLUSIONS: Intranuclear holes do occur in parathyroid neoplasia, in rare cases with considerable frequency. When intranuclear holes are observed in aspiration cytology specimens from the thyroid region, various thyroid and parathyroid conditions must be considered.

Expression of PRAD1/cyclin D1, retinoblastoma gene products, and Ki67 in parathyroid hyperplasia caused by chronic renal failure versus primary adenoma.

BACKGROUND: In primary hyperparathyroidism, certain genetic abnormalities responsible for parathyroid tumorigenesis are proposed, and it has been reported that the overexpression of PRAD1/cyclin D1 induced by a DNA rearrangement of the parathyroid hormone (PTH) gene is one of the genetic disorders in a number of primary parathyroid adenomas. However, in secondary hyperparathyroidism caused by uremia, the mechanism of monoclonal proliferation in nodular parathyroid hyperplasia is not well understood. To elucidate the mechanism, we examined the expression of PRAD1/cyclin D1, retinoblastoma gene products, and Ki67 in primary adenoma and secondary hyperplasia. METHODS: In adenomas (N = 15) and associated glands (N = 7) with normal histology obtained from patients with primary hyperparathyroidism and in diffuse (N = 14), multinodular (N = 58), and single nodular (N = 28) glands from patients who underwent parathyroidectomy for renal hyperparathyroidism, the expression of these cell cycle regulators was evaluated by immunohistochemical technique. A labeling index was used to define the proportion of cells with positive nuclear staining by each antibody. RESULTS: In 6 out of 15 (40%) primary adenomas, PRAD1/cyclin D1 was overexpressed (a labeling index of more than 500), possibly because of the PTH gene rearrangement, but not in secondary hyperplasia, including single nodular glands. Compared with diffuse hyperplasia, nodular hyperplasia showed a significantly higher expression of PRAD1/cyclin D1 (P < 0.05), retinoblastoma gene products (P < 0.05), and Ki67 (P < 0.05). However, no statistically significant correlation between the expression of PRAD1/cyclin D1 and that of Ki67 was observed in both primary adenoma and secondary hyperplasia. CONCLUSIONS: These results suggest that in secondary hyperplasia caused by uremia, at least remarkable overexpression of PRAD1/cyclin D1 induced by PTH gene rearrangement may be not the major genetic abnormality responsible for tumorigenesis. Heterogenous genetic changes seem to contribute to monoclonal proliferation of parathyroid cells induced by the expression of PRAD1/cyclin D1 or by some other mechanism independent of the amplification of the proto-oncogene.

Clear cell neoplasms of the endocrine system and thymus.

Clear cell tumors of the endocrine system and thymus are rare lesions with which surgical pathologists have only infrequent contact. As a result, these neoplasms may be misinterpreted and incorrectly classified. This review considers the histological, immunohistochemical, and ultrastructural features of clear cell pituitary adenomas, parathyroid tumors, pancreatic endocrine neoplasms, adrenocortical proliferations, and thymic malignancies. Emphasis is placed throughout on differential diagnosis with microscopically-similar lesions. Clear cell endocrine tumors and thymic lesions manifest a variety of potential lineages, including examples with epithelial, neural, germ cell, and lymphoid differentiation. Because of the wide differences in behavior and recommended treatment in this group, accuracy in diagnosis is essential.

Cytopathological variables in parathyroid lesions: a study based on 1,600 cases of hyperparathyroidism.

Fine-needle aspirates and tissue sections from 120 surgically treated parathyroid (PT) lesions and histologic archive material from PT lesions in 1,500 additional cases of hyperparathyroidism were reviewed to assess the importance of various features in distinguishing PT disease from other types of lesions by aspiration cytology. We conclude that the morphologic variation shown by PT lesions is so many-sided that this distinction cannot be based on the presence or absence of a single feature only. Instead the cytologic picture as a whole must be taken into account and evaluated with full knowledge of the anatomical conditions pertaining to the lesion examined. If still in doubt, the diagnosis can be substantiated by supplementary immunocytochemical examinations.

Pathology of parathyroid tumors.

Molecular cytogenetic techniques have shown that most parathyroid adenomas are monoclonal, i.e., are true neoplasms. But even though such neoplasms may be of single-cell origin, monoclonal tumors apparently can develop from polyclonal lesions, histologically displaying a hyperplastic pattern. The histopathological diagnosis is crucial for determining the necessary scale of the surgical procedure. In routine parathyroid pathology, conventional histological examinations, including intracellular fat staining of parenchymal cells, are still the most valuable diagnostic tools. Since it is sometimes difficult to distinguish benign from malignant tumors, the only reliable carcinoma criteria are infiltrative growth or the presence of metastases. As it can be difficult or even impossible to distinguish adenomas from carcinomas in frozen sections peroperatively, paraffin-embedded sections are often required in order to corroborate the histopathological diagnosis. Carcinoma cells often show greater cellular and nuclear uniformity than do the pleomorphic cells seen in some adenomas. Mitotic activity is more obvious in carcinomas than in adenomas, but there are exceptions. In modern parathyroid pathology, immunocytochemical methods and DNA determination may be integrated as tools into the routine diagnostic examination. The use of proliferation markers has attracted increasing interest and DNA determination may also be of value, not least to assess the growth potential of parathyroid tumors. However, it remains to be seen what role the application of molecular and genetic techniques will play in improving and further developing diagnostics in parathyroid pathology.

Tc-99m-MIBI scintigraphy for detecting parathyroid adenoma and hyperplasia.

We performed scintigraphy with technetium-99m-methoxyisobutylisonitrile (MIBI) in 10 patients with parathyroid adenoma (7 lesions) or hyperplasia (9 lesions). Correlation between an amount of accumulation of MIBI and histological types of the lesions were evaluated with special reference to an amount of oxyphilic cell in the lesions. Selected lesions were also evaluated for mitochondrial density by electromicroscopy and showed increased mitochondrial density in the oxyphilic cells. All lesions equal to or above 220 mg showed positive scintigraphic results despite differences in cell types. Undetected lesions were all equal to or below 100 mg. The scintigraphic results for 2 lesions with abundant oxyphilic cells were both positive although those for 11 lesions with abundant chief cells only 6 were positive, probably because these lesions were smaller in the hyperplasia group. In conclusion, MIBI uptake in parathyroid lesions was not dependent on the cell type but either on the size or functional state of the lesions.

Paraganglioma: an unusual tumour of the parathyroid gland.

A case of paraganglioma arising within a parathyroid gland is reported. The lesion was an incidental finding in a block dissection of neck performed for squamous carcinoma of the pharynx. A well-circumscribed lesion, exhibiting the characteristic pathological features of a paraganglioma, was embedded within the right inferior parathyroid gland. Due to its location, the chief histological differential diagnosis was an unusual variant of parathyroid adenoma. Immunohistochemistry and electron microscopy assisted in reaching a diagnosis. This, as far as we are aware, is the first reported case of a paraganglioma of the parathyroid gland.

Water-clear cell adenoma of the parathyroid. A case report with immunohistochemistry and electron microscopy.

We report a water-clear cell adenoma of the parathyroid gland, a lesion which to our knowledge has not been described previously. Like its rare but well-described hyperplastic counterpart, water-clear cell hyperplasia, this adenoma is composed of cells with abundant foamy-to-granular cytoplasm and mild nuclear pleomorphism. The cells form glandular structures and cell nests separated by fine fibrovascular septae. The tumor cells stain positively with anti-parathyroid hormone and show characteristic glassy and flocculate material by electron microscopy. Unlike water-clear cell hyperplasia, water-clear cell adenoma is a solitary lesion that compresses the residual nonneoplastic parathyroid gland.

[Neuropsychiatric symptoms in primary hyperparathyroidism]. / Neuropsychiatrische Symptomatik bei primärem Hyperparathyreoidismus.

Over a period of 3 months a 51-year-old woman developed a depressive syndrome with loss of memory, inability to find words, impaired fine movements and phases of spacial disorientation. Biochemical tests demonstrated occasional slight rises in serum calcium (2.8-2.9 mmol/l) and parathormone (4.6-5.2 pmol/l). She had a grade II nodular goitre with normal thyroid function. Ultrasonography of the thyroid suggested a right cranial parathyroid adenoma, confirmed at a right thyroidectomy with resection of the right upper parathyroid, while the other parathyroid glands were grossly normal. Calcium and parathormone levels returned to normal after the operation, as did the neuropsychiatric symptoms (within two months). This typical case illustrates that even in seemingly isolated neuropsychiatric changes an organic disease, like primary hyperparathyroidism, needs to be thought of.

Large clear cell adenoma of the parathyroid in a patient with MEN-1 syndrome. Ultrastructural study of the tumour exhibiting unusual RER formations.

A 48 year old man presented with hyperparathyroidism and acromegaly. Although pancreatic tumour was not demonstrated, the diagnosis of MEN-1 syndrome was made. The parathyroid adenoma was removed surgically and investigated by histology and transmission electron microscopy and was diagnosed as large clear cell adenoma with extensive deposition of glycogen. Much of the endoplasmic reticulum was present in two special forms: annulate lamellae and the rare rail-like configurations both of which showed continuity with the conventional RER as well as with each other. No obvious correlation was apparent between presence of special RER formations and growth rate or endocrine activity of tumour; they may be regarded as signs of cellular dedifferentiation.

Ultrastructural pathology of parathyroid glands in hyperparathyroidism: a report of 69 cases.

The ultrastructural features of 69 parathyroid glands from 43 patients with hyperparathyroidism were studied to distinguish between different parathyroid lesions causing hyperparathyroidism. Samples came from 44 cases of hyperplasia, 21 of adenoma, 3 of carcinoma, and 1 from a histologically normal gland. To establish the diagnosis we took into account intraoperative findings during surgery as well as light microscopic examination. Ultrastructural features, evaluated on a semiquantitative scale, were correlated with diagnostic, clinical, and biochemical parameters. Neoplastic glands were heavier than nonneoplastic ones, and carcinomatous glands were heavier than adenomatous glands. Our findings suggest that the cellular membrane of adenomatous glands shows more folding than that of hyperplastic glands, mainly in the capillary pole. Carcinomatous glands show the greatest degree of irregularity, with the formation of microvilli-like projections. Hyperplastic glands, in turn, are richer in glycogen deposition. Secretory granules appear in higher amounts when the serum calcium level is high. These findings are not of diagnostic value by themselves, but they can be taken in consideration to aid in differential diagnosis.

[Nucleolar organizer regions of benign pathology of the parathyroids]. / Le regioni nucleoloorganizzatrici nella patologia benigna delle paratiroidi.

Nucleolar organizer regions (NOR) have DNA loops containing genes that encode for ribosomal RNA; some proteins located near the NORs are argyrophilic and by Ploton's one step method we could quantify the NORs in sections of paraffin embedded tissues. We have evaluated the number of intranuclear dots in 46 parathyroid glands from 18 parathyroidectomies. The glands were weighed and the stromal fat was evaluated by a point-counting method. AgNORs were counted in 100 cells from each gland. The mean count was 3.03 in six adenomas (A), 2.39 in six cases of primary hyperparathyroidism (PH) and 2.63 in six cases of secondary hyperparathyroidism (SH). Statistical analysis performed by Mann-Whitney U test showed that differences between A and PH groups were significant. The difference between A and SH was also significant. The residual parathyroid tissue surrounding the adenoma had a significantly lower AgNOR mean count than adenomatous cells. The AgNOR mean number can be useful in assessing normal or suppressed parathyroid tissue.

Ultrasonically guided fine needle aspiration of the parathyroid. A report of two cases.

Two cases of parathyroid adenoma were diagnosed with ultrasound-guided fine needle aspiration. Both patients were clinically suspected of having features of primary hyperparathyroidism. On aspiration, one had an associated cystic change with golden brown fluid and the other a markedly cellular aspirate. The cells aspirated were differentiated from thyroid epithelial cells.

Ultrastructural histology correlates with results of thallium-201/technetium-99m parathyroid subtraction scintigraphy.

Specimens from 15 scintigraphically true-positive adenomas (golden standard: histology), 15 false-negative adenomas, 15 true-positive hyperplasias, 15 false-negative hyperplasias, 15 true-negative normal glands from patients with hyperparathyroidism, and 15 normal glands from patients without hyperparathyroidism, all selected randomly, were studied. After fixation, sectioning and H and E staining, in all 90 tissues the number of oxyphil, chief, and clear cells was counted in five randomly selected squares (103 x 103 microns). In 30 tissues, the number of mitochondria per cell was counted in five randomly selected cells from each lesion in transmission electron photomicrographs. Total cell counts in each group and number of chief cells showed no correlation with lesion detectability by scintigraphy. However, true-positive lesions had a significantly higher number of oxyphil cells than false-negative or normal glands. Twenty-one of 30 true-positive lesions had a oxyphil-to-clear cell ratio > 1; in contrast to only two of 30 false-negative lesions and 0 of 30 normal glands (p < 0.0005). The number of mitochondria per cell was higher in oxyphil cells in true-positive lesions (adenomas: 155 +/- 58, hyperplasias: 55 +/- 18) than in chief or clear cells in false-negative or normal lesions (30 +/- 15, p < 0.001). Our data suggest that the detectability of abnormal parathyroid glands by 201TI/99mTc subtraction scintigraphy is in part dependent upon the presence of mitochondria-rich oxyphil cells.

Parathyroid glands in primary hyperparathyroidism: an ultrastructural morphometric study of 25 cases.

In parathyroid glands removed from patients with primary hyperparathyroidism (pHPT), hyperplasias and adenomas cannot be distinguished from one another by light microscopy when only one gland is available for examination. When a second gland is available, it is necessary to establish whether it is normal, suppressed, or hyperplastic. This distinction may be difficult, and the main criterion is the amount of cytoplasmic lipid in the parenchymal cells. If the lipid is abundant, the gland is considered normal or suppressed, and if it is scanty, the gland is interpreted as hyperplastic. We have performed a morphometric ultrastructural study to test the reliability of this criterion. Twenty-five adenomatous glands removed from patients with pHPT, when compared with glands of normal size from euparathyroid patients, showed a significant increase in the parameters indicative of metabolic activity, namely the size of the Golgi apparatus, the amount of rough endoplasmic reticulum, and the length of plasmalemmas. In addition, the amount of cytoplasmic lipid was significantly reduced. Furthermore, 25 glands of normal size removed from the same patients with pHPT showed an amount of lipid similar to that of normal glands from euparathyroid patients. However, all the parameters indicative of metabolic activity were significantly higher than those in glands from euparathyroid patients and comparable to those found in adenomatous glands. These results suggest that in pHPT, normal-size glands are as active as adenomatous glands, regardless of a higher lipid content.