Pheochromocytoma, a rare cause of hypertension: long-term follow-up of 55 surgically treated patients

Pheochromocytoma is a rare tumor that is found in only 0.1% of patients with diastolic hypertension. We analyze the results of our experience in management of pheochromocytomas and long-term results of its surgical treatment. From 1977 to 1996 we operated on 55 patients with a pheochromocytoma: 29 males and 27 females with an average age of 41 years (range 10-63 years). In 44 (80.0%) patients episodic hypertension or paroxysms were observed; 7 (12.7%) patients had permanent hypertension, and 4 (7.3%) had a normal arterial blood pressure (ABP). 131/123I-MIBG scintigraphy (33 patients) and magnetic resonance imaging (12 patients) showed 100% sensitivity and computed tomography (47 patients) 97.9% sensitivity. At operation five (9.1%) tumors were bilateral, five extraadrenal, and five multiple. In four (7.3%) patients an association with familial syndromes (three MEN-IIb, one von Recklinghausen disease) was observed. Five (9.1%) malignant tumors were discovered, and two patients are still alive 30 and 104 months after surgery, one of them with relapse. In 43 (78.2%) patients we preferred a flank incision, and no intraoperative deaths occurred. Mean follow-up was 88 months (6-232 months) with recurrence in only 1 (2.0%) of 50 patients without malignancy. In patients with benign pheochromocytomas the recurrence rate did not seem to be elevated in our series. Nevertheless, because the lifelong follow-up requires only annual 24-hour urinary catecholamine measurement (less than $40 per patient per year) and periodic ABP measurements, it is suggested for all patients who undergo surgery for pheochromocytoma.     

Kappa1-opioid binding sites are the dominant opioid binding sites in surgical specimens of human pheochromocytomas and in a human pheochromocytoma (KAT45) cell line

The adrenal medulla produces opioids which exert paracrine effects on adrenal cortical and chromaffin cells and on adrenal splanchnic nerves, via specific binding sites. The opioid binding sites in the adrenals are detectable mainly in the medullary part of it and differ in type between species. Thus, the bovine adrenal medulla contains mostly kappa-opioid binding sites and fewer delta- and mu-opioid binding sites while primate adrenals contain mainly delta sites and few kappa-opioid binding sites. Most chromaffin cell tumors, the pheochromocytomas, produce opioids which suppress catecholamine production by the tumor. The aim of the present work was to identify the types of opioid binding sites in human pheochromocytomas. For this purpose, we characterized the opioid binding sites on crude membrane fractions prepared from 14 surgically excised pheohromocytomas and on whole KAT45 cells, a recently characterized human pheochromocytoma cell line. Our data showed that human pheohromocytomas are heterogeneous, as expected, with regard to the production of catecholamines and the distribution and profile of their opioid binding sites. Indeed, only one out of the 14 pheochromocytomas expressed exclusively delta and mu opioid sites, while in the remaining 13 tumors kappa-type binding sites were dominant. The KAT45 cell line possessed a significant number of kappa1 binding sites, fewer kappa2-opioid binding sites and kappa3-opioid binding sites, and minimal binding capacity for delta- and mu-opioid receptor agonists sites. More specifically, the kappa1 sites/cell were approximately 18,000, the kappa2 4500/cell and the kappa3 sites 2000/cell. Our findings for the surgical specimens and the cell line combined with previously published pharmacological data obtained from KAT45 cells suggest that kappa sites appear to be the most prevalent opioid binding sites in pheochromocytomas. Finally, in normal bovine adrenals the profile of opioid binding sites differs in adrenaline and noradrenaline producing chromaffin cells. To test the hypothesis that the type of catecholamine produced by a pheochromocytoma depends on its cell of origin, we compared our binding data with the catecholamine content of each pheochromocytoma examined. We found no correlation between the type of the predominant catecholamine produced and the opioid binding profile of each tumor suggesting that this hypothesis may not be valid.     

Pediatric pheochromocytoma. A 36-year review

Fourteen children (10 boys and 4 girls, aged 8 to 17 years) had 20 pheochromocytomas treated over a 36-year period from 1959 to 1995 inclusive. Nine patients had 11 tumors before 1980; 5 children had 9 tumors up to 1987. There were no new children with pheochromocytomas at our hospital from 1988 to 1995. Hypertension, sweating, headache, and visual blurring were the most common symptoms and signs (average 5 months). The most reliable biochemical investigations were the urinary catecholamines and norepinephrine. Before 1980, intravenous pyelography and angiography were most successful in localizing the tumor, but since then ultrasonography and computerized tomography have been the radiological investigations of choice. Early involvement of the anesthesiologist in the preoperative control of the hypertension is essential; blood pressure (BP) control was achieved with phenoxybenzamine. The main anesthetic drugs used were: sodium thiopental, fentanyl, methoxyflurane, isoflurane, nitrous oxide, and metocurine. Sixteen tumors were adrenal and 4 were extra-adrenal (1 intrathoracic and 1 extradural). All except 2 tumors were completely resected; they ranged in size from 1.3 to 14 cm. Ligation of the tumor's venous drainage was usually associated with a sudden, temporary fall in systemic BP. There were 2 children with malignant tumors. Four patients had five recurrences (second pheochromocytoma) within 6 years, and all were heralded by a return of their original symptoms and signs. One girl was left with no adrenal tissue. The only complication was in a boy with a large, partly-resected malignant right adrenal tumor who had a subphrenic abscess drained and was left with a temporary bile fistula, cirrhosis, and chronic pain. All children were normotensive when discharged from hospital and remain alive and well with a follow-up of 7 to 36 years. There were no deaths. Long-term follow-up is essential. Key word Pheochromocytoma     

Tumor angiogenesis in pheochromocytomas and paragangliomas

BACKGROUND: Angiogenesis correlates with growth and likely metastases in several tumors. To determine whether it has a similar role in pheochromocytomas, immunohistochemical staining of factor VIII was done on the tumor tissue of 42 patients. METHODS: Formalin-fixed, paraffin-embedded tissue was obtained from 29 women and 13 men with 24 primary adrenal and 18 extraadrenal pheochromocytomas. Patients were divided into two groups. Group 1 included 32 patients with benign pheochromocytomas, and group 2 included 10 patients with malignant tumors evidenced by capsular or vascular invasion (six), liver metastases (three), or periaortic lymph node metastases (one). Blood vessels highlighted by factor VIII staining of endothelial cells with labeled streptavidin-biotin were counted under light microscopy. Mean vessel count within a 10 mm2 micrometer disk was calculated under x100, x200, and x400 magnification fields. RESULTS: There were no significant differences in patient age or clinical symptoms between the groups. The mean tumor size in group 2 of 8.8 +/- 5.3 cm was larger than the mean of 4.8 +/- 2.8 cm in group 1 (p < 0.005). The mean counts of vessels in the x100, x200, and x400 magnification fields were 102 +/- 48, 40 +/- 18, and 19 +/- 9 in group 1, and 203 +/- 77, 73 +/- 28, and 37 +/- 15 in group 2. The number of blood vessels in group 2 was significantly higher than in group 1 (p < 0.001) in each studied field. CONCLUSIONS: In this study the number of tumor blood vessels correlated with the invasive behavior of pheochromocytomas. Tumor angiogenesis may be useful in determining the likelihood of malignant behavior in pheochromocytomas.     

Pheochromocytomas that do not accumulate metaiodobenzylguanidine: localization with PET and administration of FDG

Many imaging methods can be used to detect pheochromocytoma, but some tumors are not detected with conventional modalities. To explore the possible usefulness of positron emission tomography (PET) after administration of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) to localize pheochromocytoma in patients with false-negative scintigrams obtained after administration of metaiodobenzylguanidine (MIBG), FDG was administered and PET was performed in two adult patients with pheochromocytomas that had never been localized despite administration of MIBG. In both patients, images were obtained dynamically for 50 minutes; then a limited truncal sequence was performed. PET enabled correct localization of the tumors. In patient 1, a tumor that had not been detected for 21 years was localized in the middle mediastinum; in patient 2, a pheochromocytoma was detected in the right adrenal gland. PET performed after administration of FDG may be useful for localization of pheochromocytomas that do not accumulate MIBG.     

Expression of adrenomedullin mRNA in adrenocortical tumors and secretion of adrenomedullin by cultured adrenocortical carcinoma cells

Immunoreactive-adrenomedullin concentrations and the expression of adrenomedullin mRNA were studied in the tumor tissues of adrenocortical tumors. Northern blot analysis showed the expression of adrenomedullin mRNA in tumor tissues of adrenocortical tumors, including aldosterone-producing adenomas, cortisol-producing adenomas, a non-functioning adenoma and adrenocortical carcinomas, as well as normal parts of adrenal glands and pheochromocytomas. On the other hand, immunoreactive-adrenomedullin was not detected in about 90% cases of adrenocortical tumors (<0.12 pmol/g wet weight (ww)). Immunoreactive-adrenomedullin concentrations ranged from 0.44 to 198.2 pmol/g ww in tumor tissues of pheochromocytomas and were 9.2 +/- 1.2 pmol/g ww (mean +/- SD, n = 4) in normal parts of adrenal glands. Adrenomedullin mRNA was expressed in an adrenocortical adenocarcinoma cell line, SW-13 and immunoreactive-adrenomedullin was detected in the culture medium of SW-13 (48.9 +/- 1.8 fmol/10(5) cells/24h, mean +/- SEM, n = 4). On the other hand, immunoreactive-adrenomedullin was not detectable in the extract of SW-13 cells (<0.09 fmol/10(5) cells), suggesting that adrenomedullin was actively secreted from SW-13 cells without long-term storage. These findings indicate that adrenomedullin is produced and secreted, not only by pheochromocytomas, but also by adrenocortical tumors. Undetectable or low levels of immunoreactive-adrenomedullin in the tumor tissues of adrenocortical tumors may be due to very rapid secretion of this peptide soon after the translation from these tumors.     

Angiography of nonfunctioning pheochromocytomas of the adrenal gland

Two patients with clinically nonfunctioning pheochromocytomas of the adrenal gland were studied angiographically. The radiological characteristics were indistinguishable from those of functioning pheochromocytomas. In patients with hypervascular adrenal masses, the diagnosis of pheochromocytoma should be considered even in the absence of customary signs and symptoms.     

I-123 MIBG scintigraphy in adults. A report of clinical experience

Thirty-one adult patients with clinical findings suggestive of pheochromocytoma were studied with I-123 MIBG. All patients had images obtained at 24 and 48 hours. Five patients had abnormal uptake proved to be because of I-123 MIBG avid tumors. The remaining 26 patients had no proven tumors and showed physiologic uptake in various organs. The 24-hour images were of high quality. In all cases, the 48-hour images contributed no significant additional information. Only in 1 patient did the 48-hour image add some certainty. Physiologic uptake was seen in the salivary glands, liver, G.I. tract, and urinary bladder in all patients (100%). Uptake was also observed in the lung and heart (90%), normal adrenal glands (32%), thyroid (29%), spleen (23%) uterus (13%), and neck muscles (6%). The authors' experience indicates that I-123 MIBG gives superior images compared to the previously used I-131 MIBG, that the optimum imaging time for adults is 18-24 hours, and that normal distribution patterns including uterine and neck muscle uptake should be familiar to physicians interpreting the studies.     

Cleveland Clinic experience with adrenal Cushing's syndrome

PURPOSE: Cushing's syndrome due to adrenal adenoma or adrenocortical carcinoma is rare. To understand better the clinical and biochemical presentation of this disorder, as well as therapy efficacy and patient survival, we conducted a retrospective review. MATERIALS AND METHODS: Between August 1971 and April 1994, 40 patients presented to our institution with adrenal Cushing's syndrome (27 adenomas and 13 carcinomas). These groups were analyzed with respect to clinical signs and symptoms preoperatively and postoperatively, biochemical analysis, length of postoperative steroid replacement therapy, disease recurrence and patient survival. Followup was obtained by chart review and telephone interviews and averaged 59.6 +/- 66.4 and 47.6 +/- 56.2 months for adenoma and carcinoma patients, respectively. RESULTS: Women predominated in both groups (26 of 27 adenomas, 11 of 13 carcinomas), and tumors affected the left adrenal gland more frequently (19 of 27 adenomas, 9 of 13 carcinomas). Adenoma patients were younger than carcinoma patients (39.6 +/- 14.4 versus 51.5 +/- 16.6 years, p = 0.026) and presented with smaller tumors (3.3 +/- 1.0 versus 8.6 +/- 4.5 cm., p = 0.001). There was a trend toward increased incidence of glucose intolerance among carcinoma patients but no significant differences in clinical signs or symptoms between adenoma and carcinoma patients could be made. Similarly, while there was no significant difference in biochemical evaluation of adenoma versus carcinoma patients, 24-hour urinary free cortisol and serum lactate dehydrogenase levels tended to be higher among carcinoma patients. In addition 17-ketosteroid and dehydroepiandrosterone sulfate levels were more elevated in carcinoma than in adenoma patients, and several adenoma patients actually had subnormal levels. Among adenoma patients mean length of steroid replacement therapy was 16.8 +/- 9.1 months. However, 7 adenoma patients (25.9%) required greater than 24 months of exogenous steroids, and only 1 of these patients was subsequently weaned off steroid replacement. There were no recurrences among adenoma patients, although there was 1 perioperative death due to hypoglycemia. Ten (76.9%) carcinoma patients had recurrences at a mean followup of 33 months. The 3 and 5-year survival rates were 41.5 and 31.2%, respectively. CONCLUSIONS: While presenting signs and symptoms and hormonal analysis may suggest benign or malignant disease, only tumor size and patient age are reliable preoperative indicators of adrenal adenoma versus adrenocortical carcinoma among patients with adrenal Cushing's syndrome. Surgery is curative for adenoma patients, but lifelong steroid replacement may be required. Survival remains poor among carcinoma patients.     

Pre-Cushing's syndrome not recognized by conventional dexamethasone suppression-tests in an adrenal "incidentaloma" patient

Pre-Cushing's syndrome has been recently diagnosed in 6-12% of patients affected with incidentally discovered adrenal masses. Some of these patients have been described to show transient hypoadrenalism after surgery, similarly to those affected with overt Cushing's syndrome. We studied a 70-year-old male patient with a large left adrenal mass, incidentally discovered, who displayed 24-h urinary free cortisol levels at the upper limit of the normal range, normal dexamethasone overnight and low-dose suppression tests and not suppressed ACTH levels, increased 17-hydroxyprogesterone response to ACTH stimulation and low upright plasma renin activity with normal serum aldosterone levels; furthermore, DHEAS level was low and 75 Selenium-cholesterol scintigraphy showed unilateral uptake concordant with the side of the mass. Soon after left adrenalectomy, he complained of acute hypoadrenalism requiring cortisol replacement therapy: ten months after surgery he is still hypoadrenal. Moreover, stimulated 17-hydroxyprogesterone and plasma renin activity in clino- and orthostatic posture have become normal. We propose that conventional dexamethasone suppression-tests may be not enough sensitive in this kind of patients and that in selected cases the absence of controlateral uptake at scintigraphy may be more reliable in predicting post-surgical hypoadrenalism.     

Questionability of the benefits of routine laparotomy as the surgical approach for pheochromocytomas and abdominal paragangliomas

BACKGROUND: Improvement of preoperative imaging of pheochromocytomas and abdominal paragangliomas may render routine laparotomy questionable as the surgical approach of choice for these lesions. METHODS: We studied the records of 100 patients with chromaffin tumors who underwent abdominal exploration. The disease was familial in 28 patients and was malignant in 19. Seventy-five patients had intraadrenal disease (bilateral in 13). Computed tomography (CT), metaiodobenzylguanidine (MIBG) scintigraphy, and magnetic resonance imaging (MRI) were performed since 1979, 1984, and 1987 in 97, 73, and 43 patients, respectively. False-positive and false-negative results were defined as any discrepancy between imaging results and surgical findings. RESULTS: Overall accuracy of preoperative localization was 85% with CT scan, 77% with MIBG scintigraphy, and 86% with MRI. In unilateral pheochromocytoma, accuracy was 94% with CT scan, 80% with MIBG scintigraphy, and 96% with MRI. When all three studies were performed (n = 38), overall accuracy was 97% and only one extraadrenal tumor in a patient with familial pheochromocytoma was overlooked. CONCLUSIONS: The outstanding accuracy of available imaging techniques questions the strategy of routine laparotomy for sporadic and seemingly benign pheochromocytomas, favoring more elective approaches such as the posterior approach or laparoscopy.     

Approximation to conservative surgery of Leydig cell tumor

OBJECTIVES: To analyze the clinical and histological characteristics of 5 cases of Leydig cell tumor in order to establish the criteria for conservative surgical management. METHODS: Of 31 testicular tumors diagnosed from 1982-1993, 5(16.1%) were Leydig cell tumors. We analyzed patient general characteristics, the prevalent feminizing (60%) and hypogonadal features and the histopathological characteristics that might indicate a non aggressive course of the tumor. RESULTS: No metastasis was observed at 522.9 months mean follow up. Three patients underwent orchidectomy through the inguinal approach; one case had been incidentally discovered after subalbuginea resection due to a disseminated prostatic carcinoma and the fifth patient was treated conservatively by tumorectomy and is tumor-free at more than 120 months follow up. CONCLUSIONS: Parenchyma-sparing surgery may have a place in the treatment of interstitial cell tumor, with evident endocrinological and psychological benefits, especially in the young males that meet the clinical and histological criteria for conservative surgical management.     

Transcutaneous electrical nerve stimulation and temporary S3 neuromodulation in idiopathic detrusor instability

PURPOSE: We studied the effects of electrical stimulation on idiopathic detrusor instability. MATERIALS AND METHODS: Between January 1993 and December 1994, 30 men and 41 women (mean age plus or minus standard deviation 48 +/- 16 years) underwent transcutaneous electrical nerve stimulation (TENS) of the S2-S3 dermatomes, and 13 men and 22 women (mean age 48 +/- 12 years) underwent S3 neuromodulation. Subjective assessment was performed using a diary and symptom score of 0 to 14. Objective outcome was analyzed with urodynamic studies. RESULTS: Mean duration of TENS was 3 +/- 1 weeks (range 2 to 4). Although there were no major complications 31% of the patients reported local skin irritation. The overall urinary symptom scores improved from 10 +/- 2 (range 5 to 14) before the study to 7 +/- 3 (range 1 to 14) during stimulation. Urodynamic analysis revealed significant (p < 0.05) improvements in total bladder capacity and voided volume, and decreases in the number and frequency of unstable contractions. Mean duration of S3 neuromodulation was 6 +/- 1 days (range 4 to 8 days). Four procedures failed due to electrode displacement in 3 cases and procedure intolerance in 1. Hemorrhage from the puncture site occurred in 1 patient. Overall urinary symptom scores were 10 +/- 3 (range 5 to 14) before the study and 5 +/- 2 (range 2 to 10) during stimulation. Although symptomatic relief was more pronounced with S3 neuromodulation, no statistically significant differences were found regarding urinary symptoms compared to TENS. CONCLUSIONS: In patients with severe detrusor instability refractory to conservative treatments the use of TENS and S3 neuromodulation produced significant changes in urodynamic parameters and presenting symptoms. Our results appear to justify evaluation with neuromodulatory techniques before definitive surgical intervention in these patients.     

Microwave disinfection of denture base materials colonized with Candida albicans

OBJECT: Guglielmi detachable coil (GDC) technology is a valuable therapeutic alternative to the surgical treatment of ruptured or incidental intracranial aneurysms. The authors describe their technical and clinical experience in the use of the GDC technique in patients who underwent endovascular occlusion for the treatment of incidentally found intracranial aneurysms. METHODS: One hundred fifteen patients with 120 incidentally found intracranial aneurysms underwent embolization by means of the GDC endovascular technique. Ninety-one patients were females and 24 were males. Patient age ranged from 13 to 80 years. In 64 patients the incidental aneurysms were discovered when unrelated nonneurological conditions signaled the need for angiography or magnetic resonance angiography (Group 1). Twenty patients who presented with incidental aneurysms that were discovered during treatment for an acutely ruptured aneurysm underwent treatment of both types of aneurysm during the acute phase of subarachnoid hemorrhage (SAH) (Group 2). Sixteen patients with incidental aneurysms were treated during the chronic phase of SAH (Group 3). Group 4 included 15 patients who had incidental aneurysms associated with brain tumors or arteriovenous malformations. Angiographic results revealed complete or near-complete occlusion in 109 aneurysms (91%) and incomplete occlusion in five aneurysms (4%). Guglielmi detachable coil embolization was attempted unsuccessfully in six aneurysms (5%). One hundred nine patients (94.8%) remained neurologically intact or unchanged from their initial clinical status. Five patients (4.3%) deteriorated as a result of immediate procedural complications. All these complications occurred in the first 50 patients treated in the series. No clinical complications were observed in the last 65 patients. In one patient, a partially embolized aneurysm ruptured 3 years postprocedure. In Groups 1 and 3, the average length of hospitalization was 3.3 days. CONCLUSIONS: The evolution of GDC technology has proved to provide safe treatment of incidental aneurysms (a morbidity rate of 0% was achieved in the last 65 patients). The topography of the aneurysm and the clinical condition of the patient did not influence final anatomical or clinical outcomes. The GDC technology also confers a positive economic impact by decreasing hospital length of stay and by eliminating the need for postembolization intensive care.     

Meckel's diverticulum in childhood. The authors' own experience

Meckel's diverticulum occurs in approximately 2 percent of the population and may present at any age. Although Meckel's diverticulum may produce an intestinal obstruction or perforation, simulating an appendicitis, hemorrhage is its most important clinical presentation. From 1989 to 1994, Meckel's diverticulum was discovered in ten children at laparotomy. Three cases were asymptomatic, representing an incidental finding at laparotomy. Of the seven symptomatic patients, four presented with bowel obstruction (intussusception), three had rectal bleeding one of whom had diverticulitis. Contrast studies--in gastrointestinal hemorrhage--were not helpful in establishing the diagnosis; colonoscopy and gastroscopy ruled out other causes of bleeding. Five of seven symptomatic patients had an intestinal resection while two a diverticulectomy after assessment that the ulcer did not require resection. No postoperative morbidity and mortality is reported in either groups. A Meckel's diverticulum found incidentally at laparotomy should be always resected as the risk of complication is high and that of resection low.     

Psychological symptoms in rural road trauma victims

There continues to be controversy regarding the optimal evaluation and treatment of adrenal tumors. Magnetic resonance imaging, metaiodobenzylguanidine scan, single-photon emission tomography imaging, endoscopic ultrasound, and radiolabeled somatostatin analogues are just a few of the newer imaging techniques being investigated to improve our ability to obtain a specific diagnosis of an adrenal mass. Although the diagnosis and treatment of pheochromocytomas are relatively straightforward, the evaluation and treatment of incidentally discovered adrenal masses is less clear-cut. The management of an incidentaloma is guided by two principle considerations: whether the tumor has hormonal activity, and its malignant potential. In addition to diagnostic advances, refinements continue to be made regarding surgical management of these lesions. Laparoscopic adrenalectomy is fast becoming the procedure of choice for benign-appearing adrenal masses with appropriate indications for operative removal.     

Adrenal gland myelolipoma: review of the bibliography regarding a case

OBJECTIVE: To describe an additional case of this rare disease entity, with special reference to its diagnosis and treatment, and to briefly review the literature. METHODS: We report on an 82-year-old male with adrenal myelolipoma that had been incidentally discovered during evaluation for another condition. A left adrenalectomy was performed due to the large size of the tumor and in order to determine its benign or malignant nature. RESULTS: The histopathological findings disclosed an andrenal myelolipoma. CONCLUSIONS: Adrenal myelolipoma is an uncommon tumor type. CT is the most effective diagnostic method. Surgery is advocated in symptomatic cases and in asymptomatic cases with a large tumor mass.     

Immunohistochemical localization of endothelin-1, endothelin-3 and endothelin receptors in human pheochromocytoma and paraganglioma

Endothelin (ET) and its receptor system have been shown to exert various biological effects on different types of cells in addition to their well-known vasoconstrictor activity. Recently ET-1, ET-3 and the ETB receptor have been shown to play an important role in the development of neural crest-derived cells and, in this context, pheochromocytomas have been reported to harbor ET-1. Endothelin-3 or ET receptor subtypes, however, have not been examined in pheochromocytoma and paraganglioma so far. In the present study the immunohistochemical localization of ET-1/big ET-1, ET-3/big ET-3 and the ETA and ETB receptors were investigated to clarify the biological characteristics of these two tumors using 32 pheochromocytomas and 11 extra-adrenal paragangliomas. Endothelin-1/big ET-1 was detected in 19 pheochromocytomas (59%) and eight paragangliomas (72%), while ET-3/big ET-3 was detected in 10 pheochromocytomas (31%) and three paragangliomas (27%). The ETA receptor was found in 21 pheochromocytomas (66%) and in eight paragangliomas (73%), while the ETB receptor was found in 25 pheochromocytomas (78%) and in eight paragangliomas (73%). Normal adrenomedullary cells lacked each antigen examined. Endothelin-immunoreactive tumor cells were distributed focally or in a manner scattered, while receptor-immunostained tumor cells were distributed with a focal pattern for the ETA receptor and with a focal or diffuse pattern for the ETB receptor. Endothelin and its receptor coexisted in the same tumor in 21 of 28 ET-positive pheochromocytomas and in eight of 10 ET-positive paragangliomas. In addition, seven pheochromocytomas and two paragangliomas revealed positivity of the receptor(s) irrespective of the absence of ET-immunoreactivity. In conclusion, ET and its receptor are frequently and concomitantly expressed in the pheochromocytoma and paraganglioma. From the highly frequent expression of this system or the receptor(s), ET-receptor-mediated signal transduction of these tumors concerning growth and/or cell survival is expected, although definite biological significance of this ligand-receptor system in these tumors awaits further investigation.     

Serum bilirubin distribution and its relation to cardiovascular risk in children and young adults

The discovery of an asymptomatic adrenal mass (incidentaloma) during the investigation of an unrelated condition is relatively common. In this study, we report the clinical, radiologic, and endocrine evaluation of 38 patients (22 women and 16 men aged 24 to 84 years) with adrenal incidentaloma (size, 1 to 12 cm). The patients underwent basal and dynamic evaluation of the hypothalamic-pituitary-adrenal (HPA) axis, renin-angiotensin-aldosterone system, and adrenomedullary function. Moreover, computed tomograpy (CT) scan and 131I-6beta-iodomethyl-19-norcholest-5(10)-en-3beta-ol(NP-59) and/or 131I-metaiodobenzylguanidine (MIBG) scintigraphy were performed. The endocrine evaluation indicated two cases of pheochromocytoma and four cases of preclinical Cushing's syndrome, three of which underwent surgery with histologic diagnosis of two adrenocortical adenomas and one carcinoma. Low levels of serum dehydroepiandrosterone sulfate (DHEA-S), associated with a markedly increased 17-hydroxyprogesterone (17-OHP) response to a corticotropin (ACTH) test, were found in patients with incidentaloma. On the basis of endocrine and morphologic data, 13 patients underwent surgical treatment: five adrenocortical adenomas (two functioning), two pheochromocytomas, two ganglioneuromas, one cortisol-secreting adrenal carcinoma, one lymphangiomatous cyst, one myelolipoma, and one hemorrhage were found. Careful diagnostic assessment of incidentally discovered adrenal masses must be performed to exclude the presence of malignant and/or functioning lesions and to verify the possibility that patients with incidentaloma have a genetic or acquired deficit of adrenal steroidogenic activity.