Maternal perinatal undernutrition alters neuronal and neuroendocrine differentiation in the rat adrenal medulla at weaning

Epidemiological studies suggest that chronic adult diseases, such as type 2 diabetes and hypertension, can be programmed during fetal and early postnatal life. The nervous system regions governing vegetative functions and the hypothalamic-pituitary-adrenal axis are particularly sensitive to the perinatal nutritional status. Despite recent reports demonstrating that the activity of the sympathoadrenal system can be altered by early life events, the effects of maternal nutrient restriction on the adrenal medulla remain unknown. Using a rat model of maternal perinatal 50% food restriction (FR50) from the second week of gestation until weaning, immunohistochemical experiments revealed alterations in chromaffin cell aggregation and in nerve fiber fasciculation in the adrenal medulla of FR50 pups. These morphological changes were associated with enhanced circulating levels of catecholamines after decapitation (epinephrine by 55% and norepinephrine by 41%). Using macroarrays, we identified several genes whose expression was affected by maternal nutrient restriction. Semiquantitative RT-PCR confirmed the overexpression of four genes involved in neuroendocrine differentiation and neuronal plasticity (chromogranin B, growth-associated protein 43, neurofilament 3, and Slit2) in the adrenal glands of FR50 rats. Using in situ hybridization, we showed that these genes are solely expressed in the adrenal medulla. Together, our results suggest that perinatal maternal undernutrition markedly alters the differentiation of the adrenal medulla during postnatal life, resulting in enhanced activity of chromaffin cells at weaning. These alterations may persist in adulthood and participate to the programming of chronic adult diseases.

Multiple endocrine neoplasia type 2 and the RET protooncogene: from bedside to bench to bedside

Although the initial characterization of the various MEN-2 associated phenotypes (familial medullary thyroid cancer, multiple endocrine neoplasia 2A and 2B) evolved at the bedside, it was at the bench where the underlying RET (REarranged during Transfection) germline mutations were identified. Molecular information has revolutionized our understanding and continues to transform the clinical management of this fascinating endocrine tumor syndrome of neural crest derivation, which consists of medullary thyroid cancer, pheochromocytoma, and parathyroid hyperplasia/adenoma. DNA-based identification of RET carriers did not require comprehension of the gene, but was a prerequisite for clarifying gene function and devising biologic compounds blocking RET phosphorylation. With the continuing expansion of our knowledge about the underlying molecular mechanisms and our growing therapeutic abilities, multiple endocrine neoplasia type 2 is gradually returning home to the bedside, closing the loop from bedside to bench to bedside.

Topographic molecular profile of pheochromocytomas: role of somatic down-regulation of mismatch repair

CONTEXT AND OBJECTIVE

Despite extensive molecular investigation of adrenal pheochromocytomas, no information is available on their molecular and mismatch repair (MMR) profiles by topographic compartments.

DESIGN AND SETTING

Microdissected samples from the peripheral and internal zones of 143 pheochromocytomas from a referral hospital (95 sporadic and 48 associated with multiple endocrine neoplasia type 2A) were selected for loss of heterozygosity and single nucleotide polymorphism analyses. Five polymorphic DNA regions from TP53, RB1, WT1, and NF1 were systematically studied by PCR-denaturing gradient gel electrophoresis. PATIENTS, OUTCOME MEASURES, AND INTERVENTIONS: Pheochromocytomas were classified as malignant (16 sporadic tumors with distant metastases), locally invasive (30 sporadic tumors showing retroperitoneal infiltration only), and benign (all remaining tumors). Statistical differences were evaluated using Fisher's exact test. MMR was assessed by MLH1/MSH2 sequencing and immunostaining in pheochromocytomas with two or more abnormal microsatellites. No interventions were performed in this study.

RESULTS

Loss of heterozygosity/single nucleotide polymorphism involved TP53 in 40 of 134 informative cases (29.9%), RB1 in 22 of 106 informative cases (20.8%), WT1 in 32 of 120 informative cases (26.7%), and NF1 in 32 of 80 informative cases (40.0%). More genetic abnormalities involving the peripheral compartment were revealed in 34 pheochromocytomas (23.8%): 12 of 16 malignant, 10 of 30 locally invasive, and 12 of 97 benign. Multiple and coexistent genetic abnormalities characterized malignant pheochromocytomas (P < 0.001), whereas locally invasive pheochromocytomas showed a significantly higher incidence of NF1 alterations (P < 0.001). No mutations were identified in MLH1/MSH2, but MMR proteins significantly decreased in peripheral compartments.

CONCLUSIONS

Multiple microsatellite alterations and topographic intratumor heterogeneity characterize malignant pheochromocytomas, suggesting a multistep tumorigenesis through somatic topographic down-regulation of MMR proteins. Locally invasive pheochromocytomas reveal topographic heterogeneity and single-locus microsatellite alterations, especially involving NF1.

Chromogranin A deficiency in transgenic mice leads to aberrant chromaffin granule biogenesis

The biogenesis of dense-core secretory granules (DCGs), organelles responsible for the storage and secretion of neurotransmitters and neuropeptides in chromaffin cells, is poorly understood. Chromogranin A (CgA), which binds catecholamines for storage in the lumen of chromaffin granules, has been shown to be involved in DCG biogenesis in neuroendocrine PC12 cells. Here, we report that downregulation of CgA expression in vivo by expressing antisense RNA against CgA in transgenic mice led to a significant reduction in DCG formation in adrenal chromaffin cells. The number of DCGs formed in CgA antisense transgenic mice was directly correlated with the amount of CgA present in adrenal medulla. In addition, DCGs showed an increase in size, with enlargement in the volume around the dense core, a phenomenon that occurs to maintain constant "free" catecholamine concentration in the lumen of these granules. The extent of DCG swelling was inversely correlated with the number of DCGs formed, as well as the amount of CgA present in the adrenal glands of CgA antisense transgenic mice. These data indicate an essential role of CgA in regulating chromaffin DCG biogenesis and catecholamine storage in vivo.

Sustentaculoma

A case of a morphologically distinctive tumor of the adrenal medulla occurring in a 54-year-old woman is described. On microscopic examination, the tumor was well circumscribed and characterized by the presence of ill-defined, irregular nests of spindle cells with oval to elongated nuclei, tiny nucleoli, and abundant eosinophilic cytoplasm. The tumor was associated with a moderate infiltrate of lymphocytes and plasma cells with occasional lymphoid follicles. Necrosis, marked cellular atypia, and mitoses were absent. Immunohistochemical studies demonstrated the tumor cells to be strongly reactive for vimentin, S-100 protein, and CD56, and nonreactive for glial fibrillary acidic protein, chromogranin, synaptophysin, melanoma-associated antigens, and dendritic cell markers. Ultrastructural examination showed elongated cells with interdigitating cytoplasmic processes devoid of a basal lamina. No secretory granules were noted. The morphology, immunophenotype, and ultrastructure of this unique neoplasm suggest derivation from sustentacular cells of the adrenal medulla. We propose the designation "sustentaculoma" for this hitherto undescribed neoplasm of the adrenal gland.

Histopathology and immunohistochemistry of adrenal medullary tumors and paragangliomas

Paragangliomas arise from sympathetic or parasympathetic paraganglia and should now be defined by their site and type. The term pheochromocytoma is reserved for intra-adrenal tumors. This short review discusses the gross and microscopic features, the immunohistochemical profile, the problem of recognizing malignant potential, and the rare instances where a differential diagnosis has to be considered.

[Innervation of adrenal glands in some types of cardiovascular pathology]

We examined adrenal glands obtained at early autopsy of 56 men aged 21-70 years. According to the age five groups of cases were distinguished. The study was performed with the use of methods of silver impregnation of nerve plexuses and planimetric pointcounting. Density of nerve plexuses in adrenal medulla was significantly increased by 30 years of age due to the development of nervous relations in this organ. After age of 30 years density of nerve plexuses in adrenal medulla remained relatively stable providing high morphofunctional activity of adrenal glands. Morphological and morphometrical changes in nervous plexuses of adrenal medulla of patients were associated with cardiovascular diseases.

Differential expression of human telomerase catalytic subunit mRNA by in situ hybridization in pheochromocytomas

In pheochromocytomas, it is very difficult to predict malignant potential by conventional histology or immunohistochemical and molecular markers. We investigated the expression of human telomerase catalytic component (hTERT) mRNA, hTERT protein, Ki-67 antigen, and p27kip1 in pheochromocytomas (27 benign, 7 suspected malignant, and 7 malignant), and evaluated the possibility of expressions of these proteins, and hTERT mRNA serve as diagnostic markers for predicting the biological behavior of these tumors. All tumors showed the classical histology and typical immunohistochemical pattern. By in situ hybridization, hTERT mRNA was expressed in 5/7 malignant tumors (defined as the presence of metastasis and/or extensive local invasion) as compared with 3/27 benign tumors. We examined the hTERT by immunohistochemistry to confirm the mRNA. hTERT mRNA expression was correlated with hTERT protein expression. All benign tumors exhibited no immunopositivity or <1% of cells stained for Ki-67 antigen. Six out of seven malignant tumors have shown either hTERT mRNA expression or Ki-67 immunoreactivity. While no statistical difference in p27kip1 expressions was observed among benign, malignant, and suspected malignant tumors, there was a statistical difference between the normal adrenal medulla samples and tumors (p < 0.001). Thus, hTERT mRNA detection by in situ hybridization, hTERT expression, and Ki-67 antigen expression are all useful tools for differentiating malignant from benign pheochromocytomas.

Diethylstilbestrol-induced prolactinoma: dose-related tumor growth and effect of catecholaminergic cells on prolactin tumor cells

BACKGROUND

Prolactinoma is a pituitary adenoma originating from prolactin-secreting epithelial cells of the adenohypophysis. Unfortunately, there appears to be a relatively high recurrence rate despite all pharmacological, radiological, and surgical therapeutic interventions. The aim of the present study was to evaluate the extent of involvement of the dopaminergic dysregulation hypothesis of prolactinomas. We transplanted, in rats, DES-induced prolactinoma cells into the adrenal medulla or under the renal capsule, two tissues rich and poor in catecholaminergic innervation, respectively.

METHODS

Prolactinoma was dose-dependently induced in ovariectomized female rats implanted with 10 and 20 mg DES, and tumor cells taken from prolactinoma induced by 20 mg DES were either transplanted under the renal capsule or into the adrenal medulla.

RESULTS

Although the adrenal medulla, with its high dopamine content to inhibit prolactin secretion, was devoid of any tumoral development, a significant tumoral development was evident under the renal capsule, seemingly because of no inhibitory control over prolactin secretion coexisting with the dopamine deficiency of the tissue. Results are discussed for an alternatively possible regression and prevention of any relapse of prolactinoma, most possibly occurring because of tuberoinfundibular dopamine deficiency, by the implantation of another dopamine-rich tissue beside the tumoral mass.

CONCLUSION

Regression and prevention of any relapse of a tumoral outgrowth, most possibly occurring because of tuberoinfundibular dopamine deficiency, can well be alternatively achieved by the implantation of another dopamine-rich tissue beside the tumoral mass prolactinoma.

Subacute oral toxicity study of diethylphthalate based on the draft protocol for “Enhanced OECD Test Guideline no. 407”

We performed a 28-day repeated-dose toxicity study of diethylphthalate based on the draft protocol of the "Enhanced OECD Test Guideline 407" to investigate whether it has endocrine-mediated properties according to this assay. Diethylphthalate was orally administered to SD rats at doses of 0, 40, 200, and 1,000 mg/kg/day for at least 28 days, but no endocrine-mediated effects were detected based on any of the parameters examined, suggesting that diethylphthalate does not possess endocrine properties according to this assay.

Long-term outcome of a large series of patients surgically treated for pheochromocytoma

OBJECTIVE

To analyse the morbidity, mortality and long-term outcome in a consecutive series of surgically treated patients with pheochromocytoma (PC), or paraganglioma (PG), from the western region of Sweden between 1950 and 1997.

PATIENTS

All patients (n = 121) who had been hospitalized and treated for PC/PG over 47 years.

DESIGN

Retrospective review of patients with PC/PG regarding presenting symptoms, tumour characteristics, clinical management and long-term outcome after treatment.

SETTING

One referral centre for all patients from the western region of Sweden.

RESULTS

During an observation of 15 +/- 6 years, 42 patients died vs. 23.6 expected in the general population (P < 0.001). There was no intra- or post-operative mortality. Four patients with sporadic disease died of malignant PC and six with hereditary disease of associated neuroectodermal tumours. Five patients died of other malignancies, 20 of cardiovascular disease and seven of other causes. Besides older age at primary surgery, elevated urinary excretion of methoxy-catecholamines was the only observed risk factor for death (P = 0.02). At diagnosis 85% of the patients were hypertensive; one year after surgery more than half were still hypertensive. However, pre- and post-operative hypertension did not influence the risk for death versus controls.

CONCLUSION

Pheochromocytoma/PG can be safely treated by surgery. Death of malignant PC/PG was unusual, but the patients as a group had an increased risk of death. We recommend life-long follow-up of patients treated for PC/PG with screening for recurrent tumour in sporadic cases and for associated tumours in hereditary cases. This strategy would also be helpful in diagnosing cardiovascular disease at an early stage.

Transgenic mice overexpressing the wild-type form of the HMGA1 gene develop mixed growth hormone/prolactin cell pituitary adenomas and natural killer cell lymphomas

Overexpression of HMGA1 proteins is a constant feature of human carcinomas. Moreover, rearrangements of this gene have been detected in several human benign tumors of mesenchymal origin. To define the role of these proteins in cell transformation in vivo, we have generated transgenic mice overexpressing ubiquitously the HMGA1 gene. These mice developed mixed growth hormone/prolactin cell pituitary adenomas and natural killer (NK)-T/NK cell lymphomas. The HMGA1-induced expression of IL-2 and IL-15 proteins and their receptors may account for the onset of these lymphomas. At odds with mice overexpressing a wild-type or a truncated HMGA2 protein, adrenal medullar hyperplasia and pancreatic islet cell hyperplasia frequently occurred and no increase in body size and weight was observed in HMGA1 mice. Taken together, these data indicate an oncogenic role of the HMGA1 gene also in vivo.

Asymptomatic adrenal medullary hyperplasia detected with intraoperative hypertension: a case report

We report a rare case of asymptomatic adrenal medullary hyperplasia detected by chance with intraoperative hypertension during surgery for ipsilateral renal cell carcinoma. A 41-year-old male visited our hospital with a complaint of left flank pain. He had normal blood pressure and plasma catecholamine level was within normal limits. Ultrasonogram and CT scan revealed a left renal tumor but did not showed any abnormal masses in the left adrenal gland. The clinical diagnosis was renal cell carcinoma and we performed left total nephrectomy. In the process of operative manipulation, however, the blood pressure and pulse rate of this patient showed a marked increase. Pathological examination of the extirpated kidney revealed renalcell carcinoma, while the resected adrenal gland was diagnosed as adrenal medullary hyperplasia.

Increased norepinephrine-associated adrenomedullary inclusions in Parkinson's disease

The association with Parkinson's disease (PD) of adrenomedullary inclusions, known as 'hyaline globules' or 'adrenal bodies', has been reported for over 35 years. However, the common perception has been that adrenomedullary chromaffin cells cannot be recognized as pathological cells in PD. In the present study, we discovered that the number of adrenomedullary inclusions per unit area of the adrenal medulla was larger in PD and other Lewy body disorders (LBD) than in other neurological diseases and controls without any autonomic dysfunctions, and correlated with the duration of LBD. We also showed that the cells with adrenomedullary inclusions are all norepinephrine-secreting chromaffin cells. This was detected by PAS reaction following peroxidase immunohistochemistry of four proteins: chromogranin A, phenylethanolamine N-methyltransferase, S-100 protein and neurofilament protein. We also proved that the components of adrenomedullary inclusions are immunocytochemically different from those of Lewy bodies and Lewy-related neurites, as adrenomedullary inclusions were immunonegative to ubiquitin and alpha-synuclein as well as to the above four proteins. Therefore, contrary to current opinion, the norepinephrine-secreting adrenomedullary chromaffin cell is indeed another type of pathological cell in PD and other LBD.

Sympathoneural and adrenomedullary functional effects of ??2C-adrenoreceptor gene polymorphism in healthy humans

OBJECTIVES

alpha2-Adrenoreceptors restrain sympathetic nervous outflows and inhibit release of noradrenaline from sympathetic nerves. In-frame deletion of the alpha2C-adrenoreceptor subtype (alpha2CDel322-325) increases the risk of congestive heart failure. Increased delivery of catecholamines to cardiovascular receptors might explain this increased risk.

METHODS

Twenty-nine healthy African-Americans genotyped for alpha2-adrenoreceptor subtype polymorphisms underwent 3H-noradrenaline and 3H-adrenaline intravenous infusion and arterial blood sampling for measurements of rates of entry of endogenous noradrenaline and adrenaline into arterial plasma (total body spillovers) by the tracer dilution technique. Eleven subjects were homozygotes for the alpha2CDel322-325 polymorphism, nine heterozygotes, and nine non-carriers. Subjects were studied during supine rest and during and after i.v. infusion of the alpha2-adrenoreceptor antagonist, yohimbine.

RESULTS

At rest, homozygotes for the alpha2CDel322-325 polymorphism had higher total body noradrenaline spillover than did heterozygotes (t=2.90, df=18, P=0.023) or non-carriers (t=3.22, df=18, P=0.010). Adrenaline spillover was higher in homozygotes than non-carriers (t=2.61, df=18, P=0.045). Administration of yohimbine produced larger, more sustained increments in noradrenaline spillover, heart rate, and anxiety in homozygotes than in the other groups.

CONCLUSION

In healthy people, alpha2CDel322-325 polymorphism is associated with increased sympathetic nervous and adrenomedullary hormonal activities, both during supine rest and during pharmacologically evoked catecholamine release. Polymorphisms of the alpha2C-adrenoreceptor may help explain individual differences in predisposition to a variety of disorders of catecholaminergic function, such as cardiovascular disorders, depression or anxiety disorders.

Histological grading of adrenal and extra-adrenal pheochromocytomas and relationship to prognosis: a clinicopathological analysis of 116 adrenal pheochromocytomas and 30 extra-adrenal sympathetic paragangliomas including 38 malignant tumors

Pheochromocytomas and extra-adrenal sympathetic paragangliomas show varied histological patterns, and it is difficult to diagnose malignancy or predict the clinical course using current histological criteria. In the present study, we reviewed 146 sympathetic paragangliomas including 116 adrenal (102 unilateral, 14 bilateral) and 30 extra-adrenal tumors including 38 metastatic tumors. We developed a scoring scale according to the following six factors: histological pattern, cellularity, coagulation necrosis, vascular/capsular invasion, Ki-67 immunoreactivity, and types of catecholamine produced. The tumors were classified as well (WD), moderately (MD), and poorly differentiated (PD) types according to their scores. The frequency of these tumor types were 113 WD (77%), 27 MD (19%), and 6 PD (4%). Metastasis was observed in 15 of 113 WD (13%), 17 of 27 MD (63%), and all 6 PD (100%). Five-year survivals of patients with metastases were 92% with WD, 69% with MD, 0% with PD. Respective 10-yr survivals were 83%, 38%, and 0%. Differences between groups were statistically significant. The data show that using this grading scoring system for sympathetic paragangliomas correlates with both metastatic potential and patient survival.

Cyclooxygenase-2 is expressed in neuroblastoma, and nonsteroidal anti-inflammatory drugs induce apoptosis and inhibit tumor growth in vivo

Neuroblastoma is the single most common and deadly tumor of childhood and is often associated with therapy resistance. Cyclooxygenases (COXs) catalyze the conversion of arachidonic acid to prostaglandins. COX-2 is up-regulated in several adult epithelial cancers and is linked to proliferation and resistance to apoptosis. We detected COX-2 expression in neuroblastoma primary tumors and cell lines but not in normal adrenal medullas from children. Treatment of neuroblastoma cells with nonsteroidal anti-inflammatory drugs, inhibitors of COX, induced caspase-dependent apoptosis via the intrinsic mitochondrial pathway. Treatment of established neuroblastoma xenografts in nude rats with the dual COX-1/COX-2 inhibitor diclofenac or the COX-2-specific inhibitor celecoxib significantly inhibited tumor growth in vivo (P < 0.001). In vitro, arachidonic acid and diclofenac synergistically induced neuroblastoma cell death. This effect was further pronounced when lipooxygenases were simultaneously inhibited. Proton magnetic resonance spectroscopy ((1)H MRS) of neuroblastoma cells treated with COX inhibitors demonstrated accumulation of polyunsaturated fatty acids and depletion of choline compounds. Thus, (1)H MRS, which can be performed with clinical magnetic resonance scanners, is likely to provide pharmacodynamic markers of neuroblastoma response to COX inhibition. Taken together, these data suggest the use of nonsteroidal anti-inflammatory drugs as a novel adjuvant therapy for children with neuroblastoma.

Animal models of pheochromocytoma

Pheochromocytomas are neuroendocrine tumors of adrenal chromaffin cells. They are rare in all species except rats but occur with increased frequency in several human familial tumor syndromes. Concurrence of pheochromocytoma with other tumors sometimes parallels these human syndromes in rats, bovines, horses and dogs but a shared genetic basis for human and spontaneously occurring animal pheochromocytomas has thus far not been established. Pheochromocytomas are inducible in rats by a variety of non-genotoxic substances that may act indirectly by stimulating chromaffin cell proliferation. They are not known to be similarly inducible in other species but arise with increased frequency in transgenic and knockout mice that to varying degrees recapitulate human tumor syndromes. Preliminary evidence suggests that homologous somatic genetic changes might contribute to pheochromocytoma development in humans and some mouse models. The nerve growth factor-responsive PC12 cell line, established from a rat pheochromocytoma, has for almost 30 years served as a research tool for many aspects of neurobiology involving normal and neoplastic conditions. Recently developed pheochromocytoma cell lines from neurofibromatosis knockout mice supplement the PC12 line and have generated additional applications. Advantages of the mouse lines include expression of substantial levels of the epinephrine-synthesizing enzyme, phenylethanolamine N-methyltransferase and expression of high levels of the receptor tyrosine kinase, Ret, which is characteristic of sporadic and familial human pheochromocytomas but not of PC12 cells. Disadvantages include an apparently less stable phenotype. It is difficult to establish pheochromocytoma cell lines from any species, although the tumor cells persist in culture for many months. Understanding of factors that permit pheochromocytoma cells to proliferate might itself provide important insights for tumor biology.

Combined Adrenal Myelolipoma and Medullary Hyperplasia

OBJECTIVE

A patient is reported with hypertension due to combined medullary adrenal hyperplasia and myelolipoma.

METHODS

A 52-year-old woman with long-standing hypertension was evaluated for an incidentally discovered large tumor of the left adrenal. Left adrenalectomy was performed for a presumptive clinical diagnosis of pheochromocytoma.

RESULTS

Histopathologic examination revealed a mixed tumor consisting of a large myelolipoma with infiltrating foci of adrenal medulla.

CONCLUSIONS

A patient is described with hypertension, myelolipoma and adrenal medullary hyperplasia; following adrenalectomy, however, blood pressure and biochemical abnormalities normalized.

Low-Density Pheochromocytoma on CT:A Mimicker of Adrenal Adenoma

OBJECTIVE

Attenuation values on CT of less than 10 H are considered characteristic of adrenal adenomas. Adrenal pheochromocytomas can infrequently contain fat that could result in low attenuation on CT. The purpose of our study was to determine if pheochromocytomas could be confused with adenomas by virtue of their attenuation values on unenhanced CT.

MATERIALS AND METHODS

CT attenuation and size of nine adrenal nodules producing pheochromocytoma syndrome were measured on unenhanced CT in nine patients. For five patients who received IV contrast material, washout profiles were also calculated.

RESULTS

Two of the nine patients had adrenal lesions with attenuation values of less than 10 H; one had a pheochromocytoma with an attentuation of 9.0 H, and the other had a medullary hyperplasia with an attenuation of 1.8 H. These two nodules showed evidence of microscopic fat at histologic examination. No macroscopic fat was seen on the CT scans. The remaining seven patients had lesions with attenuation values exceeding 10 H (mean value, 25.6 H; range, 1.8-41 H). Mean diameter of the nine tumors (including the hyperplastic nodule) was 3.2 cm (range, 0.8-6.7 cm; SD, +/- 2.3 cm). The two low-attenuation lesions also mimicked adenomas by displaying more than 60% contrast washout on 10-min-delayed contrast-enhanced scans, unlike the other three pheochromocytomas for which we had washout data.

CONCLUSION

On CT, pheochromocytomas may have attenuation values less than 10 H and also may display more than 60% washout of contrast agents on delayed scanning. Adrenal pheochromocytomas should be included with adenomas in the differential diagnosis both for masses with low attenuation on unenhanced CT and for lesions exhibiting a high percentage of contrast washout.

[Adrenocortical tumours]

Adrenocortical tumours have to be differentiated from cortical hyperplasias, medullary tumours and extra-adrenal tumours or metastases. These diagnoses are mostly possible using routine paraffin sections. In some cases, immunostaining for differing cortical and medullary tumours and metastases are necessary. Adrenal hyperplasias can be congenital or acquired. They are diffuse, micronodular or macronodular and may be inactive or induce a cortical hyperfunction. Very rarely, macronodular hyperplasias may transform into autonomous adenomas. Primary, pigmented adrenocortical disease is a rare, special type of primary adrenal Cushing's syndrome, showing many small tumours with pleomorphic cells and an atrophic surrounding cortical tissue. Adrenal adenomas are mostly unilateral and solitary tumours weighing less than 50 g. Adrenal cortical carcinomas are mostly larger. Like the adenomas, they may be inactive and may induce a hypercortisolism, a hyperandrogenism or (very rarely in carcinomas) a hyperaldosteronism. Differentiating cortical adenomas and carcinomas is difficult in some cases but is possible using a diagnostic algorithm. Myelolipomas are benign, inactive tumours composed of mature fat cells and bone marrow cells. They have to be differentiated from adenomas with myelolipomatous metaplasia. Further, rare primary cortical tumours are mentioned.

Effects of acute administration of ethanol on the rat adrenal cortex

OBJECTIVE

The purpose of this study was to investigate the effect of a single dose of ethanol on rat adrenal cortex and to determine whether the estrous cycle can influence this effect of ethanol.

METHOD

Adult female Wistar rats showing proestrus or diestrus Day 1 (n = 12) were treated intraperitoneally with ethanol (4 g/kg body weight). Untreated (n = 15) and saline-injected (n = 14) rats were used as controls. The animals were sacrificed by decapitation 0.5 hour after ethanol administration. Stereological analysis was performed on paraffin sections of adrenal glands stained with AZAN, and the following parameters were determined: absolute volume of the zona glomerulosa, the zona fasciculata and the zona reticularis, numerical density, volume and the mean diameter of adrenocortical cells and of their nuclei, and diameter and length of capillaries.

RESULTS

The diameter and volume of adrenocortical cells in the zona fasciculata and the zona reticularis were significantly increased by acute ethanol treatment at proestrus. In the same group of animals, a single dose of ethanol induced significant decrease in numerical density of adrenocortical cells and of their nuclei in all three zones. Increased length of capillaries of the zona fasciculata as well as enhanced level of serum corticosterone was found in ethanol-treated rats at both phases of the estrous cycle, proestrus and diestrus Day 1.

CONCLUSIONS

The obtained results indicate that a single dose of ethanol activates adrenal cortex in female rats and that the effect is more pronounced on morphometric parameters at proestrus.

Corticomedullary mixed tumor of the adrenal gland with concurrent adrenal myelolipoma

We report the case of a corticomedullary mixed tumor of the adrenal gland in a 55-year-old woman with a left adrenal mass who presented with mild symptoms of Cushing syndrome and an elevated urinary cortisol level. The patient underwent a left adrenalectomy. A well-circumscribed 2.5-cm mass, composed of an admixture of adrenal cortical cells and pheochromocytes, and an incidental 0.7-cm myelolipoma were present in the resected left adrenal gland. The diagnosis of adrenal corticomedullary mixed tumor was confirmed by both immunohistochemistry and electron microscopy. To our knowledge, this is the eighth well-documented report of this rare tumor.

Primary pigmented nodular adrenocortical disease: paradoxical responses of cortisol secretion to dexamethasone occur in vitro and are associated with increased expression of the glucocorticoid receptor

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of ACTH-independent adrenal Cushing's syndrome (CS), which is often associated with Carney complex (CNC). We have recently described a paradoxical increase in cortisol excretion after dexamethasone administration in most patients with PPNAD. In the present study we investigated the hypothesis that this phenomenon is due to a primary abnormality of the tissues affected by PPNAD, rather than a defect of the patients' hypothalamic-pituitary-adrenal axis; as such it should be replicated in vitro by adrenal slices exposed directly to dexamethasone. We were able to study adrenal tissues from eight patients with CS caused by PPNAD; two patients were also studied in vivo according to a protocol first described in ACTH-independent macronodular adrenal hyperplasia (AIMAH) for the clinical detection of aberrant hormone receptor expression. Their DNA has been previously screened for inactivating mutations of the PRKAR1A gene, the most frequent molecular defect leading to PPNAD and/or CNC. We also investigated whether glucocorticoid receptor (GR) expression underlies paradoxical dexamethasone responses in PPNAD by immunohistochemistry and semiquantitative PCR, and we correlated GR expression with that of other markers for PPNAD (e.g. synaptophysin). Indeed, we demonstrated that dexamethasone induced cortisol secretion in vitro in five of these tumors; no such increase was seen in adenomatous or AIMAH tissues that were treated in the same manner. GR mRNA was expressed, and GR immunoreactivity was detected in PPNAD nodular cells. Staining for GR was not seen in surrounding cortical cells, and hence, it correlated with synaptophysin, which also stains PPNAD in a similar manner. In normal adrenal tissue, GR was detected mostly in medullary areas, whereas GR immunoreactivity was weak in adenomatous and AIMAH tissues. We conclude that 1) dexamethasone produces an increase in glucocorticoid synthesis by PPNAD adrenal slices in vitro, suggesting a direct effect on adrenocortical tissue, and 2) this phenomenon is accompanied by increased expression of the GR in PPNAD nodules. PPNAD and/or CNC patients with and without mutations leading to protein kinase A activation demonstrated in vitro and/or in vivo paradoxical dexamethasone responses and GR expression, indicating that PRKAR1A alterations are not necessary for these phenomena.

The role of calretinin, inhibin, melan-A, BCL-2, and C-kit in differentiating adrenal cortical and medullary tumors: an immunohistochemical study

Morphologic distinction between adrenal cortical and medullary tumors can be difficult. Previous studies have shown inhibin, melan-A, and BCL-2 to be useful markers for adrenal cortical tumors. We have recently observed a high level of calretinin expression in normal adrenal cortex but not the medulla and therefore evaluated its diagnostic application for adrenal tumors in comparison with inhibin, melan-A, and BCL-2. C-kit is a transmembrane tyrosine kinase receptor. Immunodetection of c-kit expression has been recently used for tumor diagnosis, and c-kit-positive tumors can potentially benefit from kit kinase inhibitor treatment. Although c-kit expression was reported in adrenal medulla and pheochromocytoma, it has not been evaluated in adrenal cortical tumors. In this study, 28 adrenal cortical tumors (12 carcinomas, 16 adenomas), 20 pheochromocytomas, and 20 extraadrenal paragangliomas were evaluated for calretinin, inhibin, melan-A, BCL-2, and c-kit expression by standard immunohistochemical assays on paraffin sections. The percentage of immunoreactivity in adrenal cortical tumors was as follows: calretinin, 96%; melan-A, 89%; inhibin, 92%; BCL-2, 20%; and c-kit, 5%. Normal adrenal medulla did not stain for c-kit but was positive for BCL-2. Eighty-six percent of pheochromocytomas stained for BCL-2 and none for calretinin, with the exception of the ganglioneuromatous areas in composite pheochromocytomas (n = 5). Extraadrenal paragangliomas showed reactivity with calretinin in 25%, melan-A in 5%, inhibin in 16%, BCL-2 in 38%, and c-kit in 8% of the cases. Our results indicate that calretinin is the most sensitive among all the adrenal markers tested. Like melan-A and inhibin, calretinin is also a very specific marker in differentiating cortical from medullary adrenal tumors. In addition, calretinin can be used to confirm a composite pheochromocytoma. BCL-2 does not appear to be useful in differentiating adrenal cortical from medullary tumors. C-kit is not useful in the diagnosis of adrenal tumors, and kit kinase inhibitor might have a limited role in the treatment of adrenal tumors and paraganglioma because of the low frequency of c-kit expression in these tumors.

[Tumors of the adrenal medulla and the paraganglia]

The sympathetic and parasympathetic paraganglia are the site of pheochromocytomas and paragangliomas. The adrenal pheochromocytoma and the abdominal paraganglioma derive from the sympathetic nervous system. The parasympathetic paragangliomas are predominantly localized in the head and neck region. Most pheochromocytomas are hormonally active and benign. The abdominal paragangliomas usually correspond to adrenal pheochromocytomas, but are more commonly malignant. The parasympathetic paragangliomas are usually benign, hormonally inactive and are most commonly located in the bifurcation of the carotid artery.

TSPY-LTA transgenic mice develop endocrine tumors of the pituitary and adrenal gland

In an attempt to determine the susceptibility of spermatogonia to malignant transformation transgenic mice were generated harboring a 1.3 kb 5'-flanking region of the germ cell specific expressed human testis specific protein, Y-encoded gene fused with the simian virus 40 large T antigen (TAg). Unexpectedly, TAg expression in transgenic mice was also detected in somatic tissues. Between days 65 and 85 after birth most of the transgenic mice developed anterior lobe tumors of the pituitary gland and to a less extent medulla type tumors of the adrenal gland. In addition, a few older transgenic mice developed tumors of the seminal vesicle, but no testicular tumors were observed in transgenic mice up to an age of 5 months. The pituitary tumors were immunoreactive for anti-prolactin (PRL) and anti-adrenocorticotropic hormone (ACTH). PRL and corticosterone concentrations in serum of transgenic mice were significantly increased. Taken together, our studies provide a novel mouse model for pituitary adenomas displaying a unique combination of hormone expression by tumor cells secreting PRL and ACTH.

Ret protein expression in adrenal medullary hyperplasia and pheochromocytoma

Ret is a developmentally regulated tyrosine kinase involved in formation and maintenance of the nervous system. Ret mutations predisposing to pheochromocytomas and medullary thyroid carcinomas occur in multiple endocrine neoplasia (MEN) syndromes 2A and 2B. Biochemical studies have demonstrated overexpression of Ret mRNA and protein in pheochromocytomas compared to normal adrenal medulla. However, the cellular distribution of Ret in the normal human adrenal and in hyperplastic lesions that antecede pheochromocytomas are unclear. The present investigation was undertaken to resolve the histological distribution of Ret in the normal human adrenal, in pheochromocytomas evolving from adrenal medullary hyperplasia in MEN2A and in sporadic pheochromocytomas. Ret expression was studied by immunohistochemistry using both a polyclonal and a monoclonal antibody, with confirmation by immunoblotting of representative cases. Only occasional cells stained for Ret in the normal adrenal, consistent with the distribution in adult adrenals of other species. Heterogeneous, progressively increased Ret expression was observed during the evolution of pheochromocytomas. In both normal and neoplastic adrenal, the most intense immunoreactivity was observed in cells with neuron-like features. Our finding that Ret is not expressed at high levels in the early stages of disease suggests that elucidation of mechanisms that regulate Ret expression is required for understanding the pathobiology of MEN2A. The association of high-level Ret expression with neuronal morphology suggests that the variable overexpression of Ret in pheochromocytomas might in part be an epiphenomenon, reflecting the known phenotypic plasticity of these tumors.

[Morphological and morphometrical changes in nervous apparatus of the adrenal medulla after sudden death of patients with various cardiac pathology]

Adrenal glands were studied at early autopsy of 28 men aged 35-60 years after their sudden cardiac death. According to the presence and character of pathologic manifestations detected in myocardium, three groups of cases were distinguished: group 1 (control) included the people without myocardial pathology (traffic accident victims), group 2 consisted of the patients with ischemic heart disease (IHD) in association with recent myocardial infarction, group 3 included the patients with IHD and hypertension. The study was performed using the methods of silver impregnation of nerve terminals and planimetric point-counting method. Analysis of density of distribution of nerve plexuses in adrenal medulla in the groups studied has shown a tendency towards its reduction in group 2 and a significant decrease in group 3. Reactive-degenerative changes in the nervous structures of adrenal medulla were detected in these two groups, while in group 3 these were accompanied by the compensatory-adaptive changes in glandular nervous apparatus. However, despite the pronounced changes found in the nervous structures of adrenal medulla, their function remained high enough, that could be explained by a transition from nervous control of adrenal activity to a humoral one.

[Misdiagnosis of corticomedullary mixed pathological changes in adrenals: report of 4 cases]

Pathological changes usually occur independently in the adrenal cortex and medulla because of their distinct embryonic origins, and changes involving both the cortex and medulla are rare. We report 4 cases of corticomedullary mixed pathological changes adrenal glands. CT scanning of the adrenal glands showed unilateral abnormalities in all the 4 cases, 3 of which were diagnosed as aldosteronism and the other pheochromocytoma before surgery. Unilateral adrenalectomy was performed in the 4 patients 3 being cured and discharged. The other 1 had recurrence 18 months postoperatively with suspected pathological changes on the other side. Subsequent pathological examination confirmed the suspicion in both the cortex and medulla of the other adrenal gland. In cases with clinical presentations as simultaneous onset of aldosteronism and catecholamine responses, pathological changes in both the cortex and medulla of the adrenal glands should be considered. Perioperative management of such cases should be the same as that in cases of catecholamine responses, and the diagnosis relies on histopathological examination.

Increased expression of adenylyl cyclase isoforms in the adrenal gland of diabetic Goto-Kakizaki rat

The spontaneously diabetic Goto-Kakizaki rat harbors the same defects expressed in human type 2 diabetes. It is not clear, however, whether stress factors emanating from the adrenal glands are involved in causing the diabetic state. For that reason, the authors studied gland size and expression of adenylyl cyclase isoforms in adrenal glands from Goto-Kakizaki and normal rats. Goto-Kakizaki rat adrenals were found to weigh only about half as much as those of control rats. This decrease was the result of a reduction of the cortex, especially of the zona fasciculata, whereas the medulla was unaffected. Cell density measurements showed that the total number of medullary cells in Goto-Kakizaki rats was lower than that in controls. In the cortex, the cell density did not differ between the two groups; thus, our results point to a marked hypotrophy. In the medulla of Goto-Kakizaki rats, the nuclear size was significantly increased, and there was also an overexpression of adenylyl cyclase 1, 2, 4, 6, and 8 isoforms in the adrenalin-producing cells, indicating an increased functional capacity. In the cortex, despite the cortical hypotrophy, adenylyl cyclase 5 immunoreactivity was markedly increased in Goto-Kakizaki rats, especially in the zona reticularis. It is unclear whether this morphologic change in the diabetic adrenal glands together with the overexpression of different adenylyl cyclase isoforms plays a role in the pathogenesis of this diabetic state or is a genetic defect or compensatory mechanism of diabetes in this spontaneous rodent model of type 2 diabetes.

Development of chromaffin cells depends on MASH1 function

The sympathoadrenal (SA) cell lineage is a derivative of the neural crest (NC), which gives rise to sympathetic neurons and neuroendocrine chromaffin cells. Signals that are important for specification of these two types of cells are largely unknown. MASH1 plays an important role for neuronal as well as catecholaminergic differentiation. Mash1 knockout mice display severe deficits in sympathetic ganglia, yet their adrenal medulla has been reported to be largely normal suggesting that MASH1 is essential for neuronal but not for neuroendocrine differentiation. We show now that MASH1 function is necessary for the development of the vast majority of chromaffin cells. Most adrenal medullary cells in Mash1–/– mice identified by Phox2b immunoreactivity, lack the catecholaminergic marker tyrosine hydroxylase. Mash1 mutant and wild-type mice have almost identical numbers of Phox2b-positive cells in their adrenal glands at embryonic day (E) 13.5; however, only one-third of the Phox2b-positive adrenal cell population seen in Mash1+/+ mice is maintained in Mash1–/– mice at birth. Similar to Phox2b, cells expressing Phox2a and Hand2 (dHand) clearly outnumber TH-positive cells. Most cells in the adrenal medulla of Mash1–/– mice do not contain chromaffin granules, display a very immature, neuroblast-like phenotype, and, unlike wild-type adrenal chromaffin cells, show prolonged expression of neurofilament and Ret comparable with that observed in wild-type sympathetic ganglia. However, few chromaffin cells in Mash1–/– mice become PNMT positive and downregulate neurofilament and Ret expression. Together, these findings suggest that the development of chomaffin cells does depend on MASH1 function not only for catecholaminergic differentiation but also for general chromaffin cell differentiation.

[Diagnosis and treatment of adrenal medullary hyperplasia (with report of 8 cases)]

OBJECTIVE

To study the diagnosis and treatment of adrenal medullary hyperplasia (AMH).

METHODS

An retrospective analysis of the clinical data of 8 patients with AMH admitted in our hospital from May 1998 to May 2002 were conducted with a review of the follow-up study.

RESULTS

CT scanning of the adrenal gland showed unilateral abnormal appearance in all 8 cases. Diagnoses of AMH in 4 patients and pheochromocytoma in the other 4 patients were established before surgery. All the patients underwent unilateral adrenalectomy, among whom 7 were cured and 1 suffered recurrence 1 month after operation because of medullar hyperplasia in the contralateral adrenal gland.

CONCLUSIONS

AMH should be differentiated from pheochromocytoma, especially from adrenal nodules shown by catecholamin assay. Definite diagnosis depends on pathological examination and surgical removal through abdominal approach is the best choice of treatment, in which both sides of the adrenal glands should be explored.

Ultrastructural criteria of malignancy of adrenal medullary tumor

Histological analysis and electron microscopy of 12 benign pheochromocytomas and 9 malignant pheochromoblastomas showed that there are no reliable histological differences between cells of benign and malignant tumor of the adrenal medulla. The ratio of ultrastructurally differentiated and undifferentiated cells in the tumor can reflect their maturity; the more ultrastructurally undifferentiated and less differentiated cells in the tumor, the higher is the malignant potential of this tumor.

Synchronous laparoscopic-assisted right hemicolectomy and right adrenalectomy

In recent years, minimally invasive surgery has been increasingly employed for the treatment of colorectal and adrenal tumors. We report an 82-year-old woman with synchronous right-sided colonic tumor and right adrenal tumor requiring resection. Preoperative workup showed a 6-cm primary right adrenal tumor with no evidence of invasion to adjacent structures. Laparoscopic removal of the two tumors was achieved with the use of a hand-port device, which assured safe retraction of the liver and meticulous dissection of the adrenal tumor, as well as port site protection during retrieval of the specimens. The whole operation lasted 270 min and our patient made an uneventful recovery.

Myelolipoma associated with adrenal ganglioneuroma

Adrenal myelolipomas are rare, benign mesenchymal tumors composed of mature adipose tissue and hematopoietic cells in varying proportions. Although the majority of cases occur as isolated adrenal lesions, myelolipomas have been described in association with various adrenal pathologic conditions. These conditions include enzyme deficiencies and hyperplastic and neoplastic lesions of the adrenal cortex, with perhaps endocrine dysfunction as a common feature. Ganglioneuroma is a benign tumor of the sympathetic nervous system that rarely produces symptoms of endocrine dysfunction. We report an unusual case of myelolipoma associated with ganglioneuroma of the adrenal medulla. The histogenesis of myelolipoma remains speculative. However, the close proximity to adrenal cortical cells within the stroma of ganglioneuroma suggests that the hormonal microenvironment may have played a role in the development of the myelolipoma.

Recovery of injured adrenal medulla by differentiation of pre-existing undifferentiated chromaffin cells

We described previous that the adrenal medulla recovers rapidly from the injuries due to salinomycin. In the present study we found the recovery to be apparently due to differentiation of pre-existing, primitive undifferentiated, chromaffin cells, rather than mitosis, as evidenced by lack of incorporation of 5-bromo-2-deoxyuridine in the differentiating and/or differentiated chromaffin cells. Electron-dense, striated fibrils observed within the necrotic cells and in the extracellular space were presumed to be intermediate degradation products. Schwann cells actively functioned as phagocytes in this study, and seemed to indirectly stimulate the differentiation of undifferentiated chromaffin cells.

Undifferentiated ganglioneuroblastoma in a sheep

Ganglioneuroblastoma, presumably originating from the adrenal medulla, was found in an 18-month-old sheep. Histologically, the tumour was mainly composed of undifferentiated neuroblasts with neuropil and occasional ganglion cells. The morphological and immunohistochemical features with respect to intermediate filament proteins and the neuroendocrine nature of the tumour are described. The neoplastic cells were positive for neuron-specific enolase, synaptophysin and vimentin.

Growth factors and cytokines in paragangliomas and pheochromocytomas, with special reference to sustentacular cells

The aim of this study was to localize various growth factors and cytokines in paragangliomas and pheochromocytomas in order to understand their possible autocrine or paracrine functions, and to compare sustentacular cells of the adrenal medulla with pituitary stellate cells. Thirteen resected tumors, 11 paragangliomas and 2 pheochromocytomas of the adrenal medulla, were studied. In addition, five surgically removed nontumorous adrenals and five nontumorous pituitaries were studied. Varying numbers of sustentacular cells were immunopositive for S-100 protein and in most instances for glial fibrillary acidic protein. Insulin-like growth factor-1 (IGF-1), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 were localized to both cell types in all cases, whereas epidermal growth factor (EGF) immunopositivity was noted in only three. In all tumors, leukemia inhibitory factor (LIF) was restricted to chief cells and EGF receptor to sustentacular cells. Nontumorous chief cells and sustentacular cells of adrenal medulla exhibited immunoreactivities similar to those of paragangliomas and pheochromocytomas. Secretory adenohypophysial cells displayed various immunoreactivities for all growth factors, receptors, and cytokines studied. Pituitary stellate cells were immunopositive for EGF, EGF receptor, IGF-1, LIF, and TNF-alpha. In conclusion, paragangliomas and pheochromocytomas are immunoreactive for a wide spectrum of growth factors and cytokines. Immunocytochemistry demonstrated similarities between sustentacular cells and stellate cells of the pituitary in addition to their similar morphology. The significance of these observations regarding paracrine activities of chief and sustentacular cells remains to be determined.

Adrenal cortical and medullar hyperplasia--a retrospective analysis of 6 cases

The features of the symptoms, laboratory tests and pathological characteristics of adrenal cortical and medullary hyperplasia were studied. In 6 cases of hypercatecholaminenia, plasma norepinephrine (NE), epinephrine (E), catecholamine (CA) and 24-h urinary vanillylmandelic acid (VMA), 17-hydroxycorticosteroid (OHCS) and 17-ketosteroid (KS) were determined. Adrenal glands were examined by CT scan and 131I-MIBG imaging. Pathological examination was performed after operation. The results showed that in 6 cases of hypercatecholaminenia (3 men and 3 women) aged from 34-50 years, the clinical features were just like "pheochromocytoma", for example, episodic headache, perspiration, palpitation, pallor, apprehension, nausea, tremor, anxiety and so on. Plasma levels of CA, NE and E were elevated in all 6 cases. 24-h urinary samples obtained at the onset revealed elevated VMA in 1 case. 24-h urinary cortisol was obviously elevated in all 6 cases. 24-h urinary 17-OHCS, 17-KS was normal. B-type ultrasound, CT, MRI and 131I-MIBG revealed 9 lateral adrenal gland diffuse or nodular enlargement in 6 cases. Pathologic examination showed adrenal cortical and medullary hyperplasia. Clinically, adrenal cortical and medullary hyperplasia resembled "pheochromocytoma". The most significant feature of this disease was both elevated plasma CA and 24-h urinary cortisol obviously. Pathologic examination showed adrenal cortex nodular hyperplasia and medullar diffuse or limit hyperplasia. Whether it is an independent disease or symptoms of the other disease has not final conclusion up till now.

Induction of orthotopic rat adrenomedullary neoplasia by intraadrenal pheochromocytoma cell transplantation

We aimed to establish a technically feasible, easily reproducible model of orthotopic adrenomedullary neoplasia. Male rats received adrenal injection of rat pheochromocytoma cells infected with the Escherichia coli gene for beta-galactosidase (lac Z). Each of 10 animals was perfused 7 or 24 days after tumor cell injection; 5 animals of each group were injected with cyclosporin. Animals without tumor cell injection served as controls. Tumor cells were identified and characterized in frozen sections by histochemical and immunohistochemical methods. Immunosuppressed animals had enlarged adrenals 7 days after tumor cell injection. In the rats without immunosuppression the adrenals seemed unaltered despite microscopic demonstration of tumor cells. After 24 days tumors had developed in all animals, weighing 50 times more than normal adrenals in animals with immunosuppression, and 9 times more in animals without immunosuppression. Intraadrenal catecholaminergic tumor cells could be identified by beta-galactosidase expression. No animal showed systemic spread. Generation of adrenomedullary neoplasia by intraadrenal pheochromocytoma cell transplantation is easily reproducible and technically feasible. This model allows simultaneous study of neoplastic and normal adrenal tissues (e.g., regarding their response to drugs intended for diagnostic and therapeutic purposes). The decreased tumor growth in animals without immunosuppression is presumably due to the high number of intraadrenal immunocompetent cells.

Primitive small round cell tumour of the adrenal gland presenting with fever of unknown origin and t(12;22)(q13;q12) cytogenetic finding

This report describes a left adrenal tumour in a 16 year old Chinese girl who presented with fever of unknown origin. The histological and ultrastructural features of the adrenal tumour were those of a primitive small round cell tumour with neuroendocrine differentiation. Cytogenetic analysis of cultured tumour cells showed a reciprocal translocation t(12;22)(q13;q12). This is the first example of such a tumour being reported in the adrenal gland. The adrenal tumour was also the cause of the fever, which subsided after the removal of the tumour.

A new splicing variant for human tyrosine hydroxylase in the adrenal medulla

It has been reported that several mRNA isoforms of tyrosine 3-monooxygenase (tyrosine hydroxylase; TH) occur only in primates. New TH isoforms produced by skipping of exon 3 in the adrenal medulla of patients with progressive supranuclear palsy (PSP) have recently been reported, J. Neurochem. 67 (1996) 19. Here, we looked for the presence of new TH isoforms in control brains and adrenal medulla and in brains from patients with PSP. We found a novel type of TH mRNA in the adrenal medulla from one of the control subjects. The mRNA lacked exon 4, resulting in a premature stop codon at amino acid 147. This result suggests the importance of alternative splicing in the regulation of TH activity.

Corticomedullary mixed tumor of the adrenal gland

Corticomedullary mixed tumors of the adrenal gland are quite rare, with only five well-documented cases reported in the literature.(1-4) Herein, we report the light microscopic and immunohistochemical features of two cases of this rare tumor. Patient 1 is a 34-year-old woman who presented with hypertension, hair loss, and amenorrhea of 1-year duration. Patient 2 is a 52-year-old woman who presented with flank pain and what appeared to be a renal mass on arteriogram with no history of hypertension, Cushing's syndrome, or other endocrine abnormalities. At surgery, the tumor was noted to arise from the adrenal gland rather than the kidney and adrenalectomy was performed. In both cases, the surgically resected specimens consisted of a well-circumscribed, single adrenal mass surrounded by a rim of uninvolved adrenal cortical tissue. The tumors were composed of adrenal cortical cells intimately admixed with pheochromocytes. Immunohistochemical studies highlighted these two cellular components. The pheochromocytes were strongly reactive with chromogranin and the sustentacular cells with S-100 protein, whereas the adrenal cortical cells reacted specifically with inhibin. Thus, we report two additional cases of mixed corticomedullary tumor of the adrenal gland. Ann Diagn Pathol 5:304-308, 2001. This is a US government work. There are no restrictions on its use.

[Transposition of pedicled adrenal gland for the treatment of adrenal medullary hyperplasia]

OBJECTIVE

To investigate the operative modes for adrenal medullary hyperplasia.

METHODS

8 cases of adrenal medullary hyperplasia were treated with transposition of pedicled adrenal gland. The inferior and the medial blood vessel of adrenal gland were ligated. The superior blood vessel of adrenal gland was formed a 5.0- 6.0 cm pedicle and dragged to the subcutaneous of dorsum.

RESULT

After follow-up for an average of 2 years, only 1 of the 8 patients did not recover as a result of psychosis and others had no symptoms but normal endocrine results.

CONCLUSION

Transposition of the pedicled adrenal gland is a simple and satisfied way to treat patients with adrenal medullary hyperplasia.

Basic and clinical aspects of intraadrenal regulation of steroidogenesis

The adrenal gland combines essential components of the autonomic nervous system and the HPA axis in close contact. From morphological analyses employing immunohistochemistry, in situ hybridization, the novel technique of laser capture microdissection, and electron microscopy, it has been has shown that the chromaffin cells of the adrenal medulla and the steroid-producing cells of the adrenal cortex are extensively intermingled and functionally interrelated. In in vitro studies, a variety of regulatory factors produced and released by the adrenal medulla were identified as playing an important role in modulating adrenocortical function. An isolated adrenocortical cell deprived of its tissue integrity, input from the nervous system, or intercellular communication with chromaffin, vascular, and immune cells of the adrenal gland, loses its normal capacity to produce glucocorticoids and to adequately respond to the homeostatic challenges of stress. Adrenocortical cells in co-culture with chromaffin cells produced ten times more glucocorticoids than the same number of pure adrenocortical cells and demonstrated marked up-regulation in the mRNA expression of cytochrome p450 enzymes and STAR in the co-culture, while this expression was down-regulated in isolated cells. Transgenic animal models of over-expression or deletion of enzymes involved in catecholamine synthesis, as well as of altered function of components of the HPA axis, provide evidence that the mutual interdependence of the sympatho-adrenal system and the HPA axis at the level of the adrenal gland is of physiologic relevance in vivo. Alterations in intercellular communications, local production of neuropeptides, growth factors and cytokines, and aberrant expression of ectopic receptors on adrenal cells have been implicated in adrenal cell growth, development, hyperplasia, tumor formation, autonomous hormone production, and autoimmune disease. Moreover, we described a direct cellular interaction of lymphocytes with adrenal cells as a novel non-cytokine mediated mechanism of immune endocrine interactions. Highlighting the importance of the extra-pituitary mechanisms of adrenocortical regulation, be them neural or immune, is a worthwhile starting point for a more complete analysis of the human stress system in vivo.

Intermittent hyperaldosteronism in a child due to an adrenal adenoma

Aldosterone producing adenoma (APA) is a rare but potentially curable form of paediatric hypertension. We report a case of APA in a 9-year-old boy, suspected due to persistent hypokalaemia. Neither BP nor initial laboratory investigations disclosed the diagnosis and the presence of an APA was suggested by functional tests and radiological findings. Histologically, a cortical tumour was found associated with a marked medullary hyperplasia of both chromaffin and ganglion cells.

CONCLUSION

This case reinforces the need for further investigations in patients with misleading clinical and laboratory data.