Prevalence of Malignancies in Patients With Primary Aldosteronism

CONTEXT

Primary aldosteronism (PA) is the most common cause of secondary hypertension. Aldosterone excess can cause DNA damage in vitro and in vivo. Single case reports have indicated a coincidence of PA with renal cell carcinoma and other tumors. However, the prevalence of benign and malignant neoplasms in patients with PA has not yet been studied.

PATIENTS AND DESIGN

In the multicenter MEPHISTO study, the prevalence of benign and malignant tumors was investigated in 335 patients with confirmed PA. Matched hypertensive subjects from the population-based Study of Health in Pomerania cohort served as controls.

RESULTS

Of the 335 PA patients, 119 (35.5%) had been diagnosed with a tumor at any time, and 30 had two or more neoplasms. Lifetime malignancy occurrence was reported in 9.6% of PA patients compared to 6.0% of hypertensive controls (P = .08). PA patients with a history of malignancy had higher baseline aldosterone levels at diagnosis of PA (P = .009), and a strong association between aldosterone levels and the prevalence of malignancies was observed (P = .03). In total, 157 neoplasms were identified in the PA patients; they were benign in 61% and malignant in 25% of the cases (14% of unknown dignity). Renal cell carcinoma was diagnosed in five patients (13% of all malignancies) and was not reported in controls

CONCLUSION

Compared to hypertensive controls, the prevalence of malignancies was positively correlated with aldosterone levels, tended to be higher in PA patients, but did not differ significantly.

Consensus statement on the diagnosis, treatment and follow-up of patients with primary adrenal insufficiency

Primary adrenal insufficiency (PAI), or Addison's disease, is a rare, potentially deadly, but treatable disease. Most cases of PAI are caused by autoimmune destruction of the adrenal cortex. Consequently, patients with PAI are at higher risk of developing other autoimmune diseases. The diagnosis of PAI is often delayed by many months, and most patients present with symptoms of acute adrenal insufficiency. Because PAI is rare, even medical specialists in this therapeutic area rarely manage more than a few patients. Currently, the procedures for diagnosis, treatment and follow-up of this rare disease vary greatly within Europe. The common autoimmune form of PAI is characterized by the presence of 21-hydroxylase autoantibodies; other causes should be sought if no autoantibodies are detected. Acute adrenal crisis is a life-threatening condition that requires immediate treatment. Standard replacement therapy consists of multiple daily doses of hydrocortisone or cortisone acetate combined with fludrocortisone. Annual follow-up by an endocrinologist is recommended with the focus on optimization of replacement therapy and detection of new autoimmune diseases. Patient education to enable self-adjustment of dosages of replacement therapy and crisis prevention is particularly important in this disease. The authors of this document have collaborated within an EU project (Euadrenal) to study the pathogenesis, describe the natural course and improve the treatment for Addison's disease. Based on a synthesis of this research, the available literature, and the views and experiences of the consortium's investigators and key experts, we now attempt to provide a European Expert Consensus Statement for diagnosis, treatment and follow-up.

Comparison of two mitotane starting dose regimens in patients with advanced adrenocortical carcinoma

CONTEXT

Mitotane is the only approved drug for treatment of adrenocortical carcinoma. Its pharmacokinetic properties are not fully elucidated and different dosing regimens have never been compared head to head.

OBJECTIVE

The objective of the study was to investigate the relationship between mitotane dose and plasma concentration comparing two dosing regimens.

DESIGN/SETTING

This was a prospective, open-label, multicenter trial of a predefined duration of 12 weeks.

PATIENTS/INTERVENTIONS

Forty mitotane-naïve patients with metastatic adrenocortical carcinoma were assigned to a predefined low- or high-dose regimen by the local investigator. Thirty-two patients could be evaluated in detail.

MAIN OUTCOME MEASURE

The difference in median mitotane plasma levels between both treatment groups was measured.

RESULTS

Despite a difference in mean cumulative dose (440 ± 142 g vs 272 ± 121 g), median maximum plasma levels were not significantly different between the two groups [high dose 14.3 mg/L (range 6.3-29.7, n = 20) vs 11.3 mg/L (range 5.5-20.0, n = 12), P = .235]. Ten of 20 patients on the high-dose regimen reached plasma concentrations of 14 mg/L or greater after 46 days (range 18-81 d) compared with 4 of 12 patients on the low-dose regimen after 55 days (range 46-74 d, P = .286). All patients who reached 14 mg/L at 12 weeks displayed a level of 4.1 mg/L or greater on day 33 (100% sensitivity). There were no significant differences in frequency and severity of adverse events. Among patients not receiving concomitant chemotherapy mitotane exposure was higher in the high-dose group: 1013 ± 494 mg/L · d vs 555 ± 168 mg/L · d (P = .080).

CONCLUSIONS

The high-dose starting regimen resulted in neither significantly different mitotane levels nor a different rate of adverse events, but concomitant chemotherapy influenced these results. Thus, for mitotane monotherapy the high-dose approach is favorable, whereas for combination therapy a lower dose seems reasonable.

Mitotane levels predict the outcome of patients with adrenocortical carcinoma treated adjuvantly following radical resection

CONTEXT

Mitotane plasma concentrations ≥ 14 mg/l have been shown to predict tumor response and better survival in patients with advanced adrenocortical carcinoma (ACC). A correlation between mitotane concentrations and patient outcome has not been demonstrated in an adjuvant setting.

OBJECTIVE

To compare recurrence-free survival (RFS) in patients who reached and maintained mitotane concentrations ≥ 1 4 mg/l vs patients who did not.

DESIGN AND SETTING

Retrospective analysis at six referral European centers.

PATIENTS

Patients with ACC who were radically resected between 1995 and 2009 and were treated adjuvantly with mitotane targeting concentrations of 14-20 mg/l.

MAIN OUTCOME MEASURES

RFS (primary) and overall survival (secondary).

RESULTS

Of the 122 patients included, 63 patients (52%) reached and maintained during a median follow-up of 36 months the target mitotane concentrations (group 1) and 59 patients (48%) did not (group 2). ACC recurrence was observed in 22 patients of group 1 (35%) and 36 patients in group 2 (61%). In multivariable analysis, the maintenance of target mitotane concentrations was associated with a significantly prolonged RFS (hazard ratio (HR) of recurrence: 0.418, 0.22-0.79; P=0.007), while the risk of death was not significantly altered (HR: 0.59, 0.26-1.34; P=0.20). Grades 3-4 toxicity was observed in 11 patients (9%) and was managed with temporary mitotane discontinuation. None of the patients discontinued mitotane definitively for toxicity.

CONCLUSIONS

Mitotane concentrations ≥ 14 mg/l predict response to adjuvant treatment being associated with a prolonged RFS. A monitored adjuvant mitotane treatment may benefit patients after radical removal of ACC.

Survivin in adrenocortical tumors - pathophysiological implications and therapeutic potential

Treatment options for adrenocortical carcinoma (ACC) are very limited. In other solid tumors, small vaccination trials targeting the anti-apoptotic molecule survivin suggested immunological and clinical benefit in selected patients. Therefore, we investigated whether survivin might be a suitable target for immunotherapy in ACC. Survivin mRNA and protein expression was assessed in adrenal tissue specimens [by real-time-PCR in 29 ACC, 24 adrenocortical adenomas (ACA) and 12 normal adrenal glands; by immunohistochemistry in 167 ACCs, 15 ACA, and 5 normal adrenal glands]. Expression was correlated with clinical outcome using Kaplan-Meier and Cox regression analyses. The anti-apoptotic role of survivin was investigated in the SW13 ACC cell line using survivin siRNA. The presence of spontaneous survivin specific T-cells in peripheral blood was assessed by FACS dextramere staining in 29 ACC patients in comparison to healthy controls. Survivin mRNA in ACC was significantly overexpressed when compared with ACA or normal adrenal glands. Immunohistochemistry confirmed survivin protein expression in 97% of the ACCs. In 83% of samples, staining was moderate or high and clinical outcome in this subgroup showed a trend towards poorer prognosis [hazard ratio for death 2.28 (95% CI 0.99-5.28); p=0.053]. Survivin knockdown in SW-13 cell significantly increased the rate of apoptosis. Finally, spontaneous survivin-reactive T cells were detectable in 3 of 29 ACC patients. In conclusion, our data suggest that survivin could play an important role in the anti-apoptotic mechanisms in ACC and provide first hints that targeting survivin might be an interesting new therapeutic approach in this rare disease.

[A 47-year-old patient with paroxysmal arterial hypertension and gastric tumors]

Arterial hypertension caused by a paraganglioma is rare and approximately one third of all cases of paraganglioma occur as part of a hereditary syndrome. Among these the Carney-Stratakis syndrome is characterized by the occurrence of paraganglioma/pheochromocytoma and gastrointestinal stromal tumors caused by germline mutations of the succinate dehydrogenase subunit genes (B-D). We report the case of a 47-year-old female patient suffering from Carney-Stratakis syndrome with an endocrine active thoracic paraganglioma which was successfully resected with the assistance of a heart-lung machine and the gastric stromal tumors were removed in a second surgical intervention.

AME position statement on adrenal incidentaloma

OBJECTIVE

To assess currently available evidence on adrenal incidentaloma and provide recommendations for clinical practice.

DESIGN

A panel of experts (appointed by the Italian Association of Clinical Endocrinologists (AME)) appraised the methodological quality of the relevant studies, summarized their results, and discussed the evidence reports to find consensus.

RADIOLOGICAL ASSESSMENT

Unenhanced computed tomography (CT) is recommended as the initial test with the use of an attenuation value of ≤10 Hounsfield units (HU) to differentiate between adenomas and non-adenomas. For tumors with a higher baseline attenuation value, we suggest considering delayed contrast-enhanced CT studies. Positron emission tomography (PET) or PET/CT should be considered when CT is inconclusive, whereas fine needle aspiration biopsy may be used only in selected cases suspicious of metastases (after biochemical exclusion of pheochromocytoma). HORMONAL ASSESSMENT: Pheochromocytoma and excessive overt cortisol should be ruled out in all patients, whereas primary aldosteronism has to be considered in hypertensive and/or hypokalemic patients. The 1 mg overnight dexamethasone suppression test is the test recommended for screening of subclinical Cushing's syndrome (SCS) with a threshold at 138 nmol/l for considering this condition. A value of 50 nmol/l virtually excludes SCS with an area of uncertainty between 50 and 138 nmol/l.

MANAGEMENT

Surgery is recommended for masses with suspicious radiological aspects and masses causing overt catecholamine or steroid excess. Data are insufficient to make firm recommendations for or against surgery in patients with SCS. However, adrenalectomy may be considered when an adequate medical therapy does not reach the treatment goals of associated diseases potentially linked to hypercortisolism.

Prevention of hypertensive crises in rats induced by acute and chronic norepinephrine excess

Calcium Channel Blockers (CCBs), competitive α-adrenoceptor blockers, and phenoxybenzamine (POB) are used for preoperative treatment of pheochromocytomas. We analyzed the protection from hypertensive crisis provided by these drugs during acute and chronic norepinephrine excess. To ensure adaptive changes during chronic norepinephrine (NE) excess, we continuously exposed male Wistar rats to NE for 3 weeks (osmotic pumps). Afterwards, blood pressure (BP) was continuously measured while NE boli (0-1000 μg/kg, i. v.) were administered before and after antihypertensive treatment in anesthetized and catheterized rats. A single dose of urapidil (10 mg/kg), nitrendipine (600 μg/kg) and POB (10 mg/kg) lowered BP from 212 ± 12 mmHg by 52 ± 7%, 31 ± 9%, and 50 ± 6%, respectively. With NE boli a maximum BP of 235 ± 29, 240 ± 30 and 138 ± 3 mmHg was measured in urapidil, nitrendipine, and POB treated animals (p<0.05). The number of hypertensive episodes (delta BP >30 mmHg) was 3 (3), 1.5 (0-3), and 0 (0-1) (p<0.05). Because of inferiority, urapidil was excluded from further testing. Chronically NE exposed rats were treated with POB (10 mg/kg/d), nifedipine (10 mg/kg/d), or vehicle for 7 days. Marked BP elevations were observed at baseline (167 ± 7, 210 ± 7 , and 217 ± 7 mmHg, p<0.01) and maximum blood pressure was 220 ± 32, 282 ± 26, and 268 ± 40 mmHg (p<0.001) with NE boli. Further stabilization was achieved combining POB pretreatment with a continuous nifedipine infusion, which effectively prevented BP elevations during NE excess. POB was the most effective drug used in monotherapy, but BP stabilization was superior using a combination of POB pretreatment with a continuous nifedipine infusion in this model.

The syndrome of inappropriate secretion of antidiuretic hormone: diagnostic and therapeutic advances

Hyponatremia is the most common electrolyte disorder and its presence predicts poor prognosis. The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is among the most frequent causes of hyponatremia and is caused by a variety of disorders and pathomechanisms, mostly related to malignancy, pulmonary, or neurologic disorders. The introduction of small molecule vasopressin receptor-2 (VR2) antagonists, so called vaptans, into clinical medicine for the treatment of SIADH makes a reliable diagnosis of SIADH mandatory. This requires structured assessment of essential and supplemental criteria of SIADH, an approach that is currently frequently neglected in clinical routine. Hypertonic saline remains the gold standard in the initial treatment of symptomatic SIADH with severe neurological deficits. However, correction of hyponatremia needs to be slow (<10-12 mmol/l within the first 24 h, and <18 mmol/l within the first 48 h, respectively) to avoid osmotic myelinolysis. Fluid restriction and demeclocyclin have been the most widely used treatments for chronic hyponatremia in SIADH. However, fluid restriction suffers from poor long-term acceptance and demeclocyclin lacks broad availability and has been associated with safety concerns. In controlled clinical trials vaptans have been shown to be efficacious both during short-term and long-term administration (up to 12 months) for mild to moderate SIADH with an acceptable safety profile. However, clinical experience with vaptans in SIADH outside of carefully monitored clinical trials remains still rather limited. Thus, careful postmarketing surveillance will be crucial to fully appreciate the risks and benefits of this new class of drugs in SIADH.

Etomidate unmasks intraadrenal regulation of steroidogenesis and proliferation in adrenal cortical cell lines

To characterize intraadrenal adaptations for inhibition of cortisol synthesis, we analyzed the effects of etomidate (ETO) on steroid hormone secretion and expression of key regulators of steroidogenesis and proliferation in human NCI-h295 adrenocortical cancer cells. Etomidate potently blocked 11beta-hydroxylase (CYP11B1), aldosterone synthase (CYP11B2), and side chain cleavage enzyme (CYP11A1). This inhibition of steroidogenesis was associated with increased expression of steroidogenic acute regulatory protein (StAR), and CYP11A1 and 17alpha-hydroxylase/17, 20-lyase (CYP17A1) protein levels, but not of the respective mRNA levels. Promoter activity of CYP11A1 and melanocortin 2 receptor (MC2R) was not increased by etomidate in treated cells compared to controls. The increase in protein levels was partially reversed by cycloheximide suggesting post-transcriptional mechanisms but also protein stabilization as underlying cause. Furthermore, ETO exhibited antiproliferative activity paralleled by a decrease in phosphorylation of MEK and ERK1, 2. In summary, ETO exhibits pleiotropic effects on adrenal function in vitro. Inhibition of steroidogenesis is followed by increased levels of steroidogenic key proteins and reduced proliferation. These changes reflect adaptations to maintain steroidogenesis at the cost of adrenal proliferation.

Improved metabolic control after 12-week dietary intervention with low glycaemic isomalt in patients with type 2 diabetes mellitus

The polyol isomalt (Palatinit) is a very low glycaemic sugar replacer. The effect of food supplemented with isomalt instead of higher glycaemic ingredients like sucrose and/or starch hydrolysates on metabolic control in patients with type 2 diabetes was examined in this open study. Thirty-three patients with type 2 diabetes received a diet with foods containing 30 g/d isomalt instead of higher-glycaemic carbohydrates for 12 weeks. Metformin and/or thiazolidindiones were the only concomitant oral antidiabetics allowed during the study. Otherwise, the participants maintained their usual diet during the test phase, but were instructed to refrain from additional sweetened foods. Before start, after 6 weeks and 12 weeks (completion of the study), blood samples were taken and analysed for clinical routine parameters, metabolic, and risk markers. Thirty-one patients completed the study. The test diet was well accepted and tolerated. After 12 weeks, significant reductions were observed for: glycosylated haemoglobin, fructosamine, fasting blood glucose, insulin, proinsulin, C-peptide, insulin resistance (HOMA-IR), and oxidised LDL (an atherosclerosis risk factor). In addition, significant lower nonesterified fatty acid concentrations were found in female participants. Routine blood measurements and blood lipids remained unchanged. The substitution of glycaemic ingredients by isomalt and the consequent on reduction of the glycaemic load within otherwise unchanged diet was accompanied by significant improvement in the metabolic control of diabetes. The present study is in agreement with findings of previous reported studies in human subjects demonstrating beneficial effects of low glycaemic diets on glucose metabolism in patients with diabetes mellitus type 2.

Low circulating androgens and mortality risk in heart failure

OBJECTIVE

Deficiency of anabolic sex steroids is common in heart failure (HF). The pathophysiological implications of this phenomenon, however, have not been fully elucidated. This clinical study investigated the significance of low serum androgen levels in HF.

DESIGN

Prospective cohort study. Patients and Methods In 191 consecutively recruited men with HF (mean age 64 years; New York Heart Association (NYHA) class I-IV 24%/35%/35%/6%) and reduced (ejection fraction (EF) <or=40%, n=96) or preserved (EF >40%, n=95) left ventricular function total and free serum testosterone, dehydroepiandrosterone sulfate (DHEAS) and sex hormone binding globulin (SHBG) were measured. The median observation period was 859 days.

RESULTS

During follow-up 53 patients (28%) died. Whereas total serum testosterone was normal in most patients (91%), free testosterone and DHEAS were reduced in 79% and 23%, respectively. DHEAS and free testosterone, but not total testosterone, were inversely associated with NYHA class (both p<0.01). Lower free testosterone and DHEAS and higher SHBG predicted all-cause mortality risk (hazard ratio (HR) 0.89, 95% CI 0.82 to 0.96 per 1 ng/dl free testosterone, p=0.004; HR 0.95, 95% CI 0.89 to 1.00 per 10 microg/dl DHEAS, p=0.058; and HR 1.18, 95% CI 1.05 to 1.33 per 10 nmol/l SHBG, p=0.006, respectively; adjusted for age and NYHA class). However, further adjustment for carefully selected confounding factors abolished these associations.

CONCLUSION

In male HF patients, low serum levels of androgens are associated with adverse prognosis, but this relation is confounded by indicators of a poor health state. The results suggest that low serum androgens develop as a sequel of this progressive multifaceted systemic disorder.

Merits and pitfalls of mifepristone in Cushing's syndrome

OBJECTIVE

Mifepristone is the only available glucocorticoid receptor antagonist. Only few adult patients with hypercortisolism were treated to date by this drug. Our objective was to determine effectiveness and tolerability of mifepristone in Cushing's syndrome (CS).

DESIGN

Retrospective study of patients treated in seven European centers.

METHODS

Twenty patients with malignant (n=15, 12 with adrenocortical carcinoma, three with ectopic ACTH secretion) or benign (n=5, four with Cushing's disease, one with bilateral adrenal hyperplasia) CS were treated with mifepristone. Mifepristone was initiated with a median starting dose of 400 mg/day (200-1000). Median treatment duration was 2 months (0.25-21) for malignant CS, and 6 months (0.5-24) for benign CS. Clinical (signs of hypercortisolism, blood pressure, signs of adrenal insufficiency), and biochemical parameters (serum potassium and glucose) were evaluated.

RESULTS

Treatment was stopped in one patient after 1 week due to severe uncontrolled hypokalemia. Improvement of clinical signs was observed in 11/15 patients with malignant CS (73%), and 4/5 patients with benign CS (80%). Psychiatric symptoms improved in 4/5 patients within the first week. Blood glucose levels improved in 4/7 patients. Signs of adrenal insufficiency were observed in 3/20 patients. Moderate to severe hypokalemia was observed in 11/20 patients and increased blood pressure levels in 3/20 patients.

CONCLUSION

Mifepristone is a rapidly effective treatment of hypercortisolism, but requires close monitoring of potentially severe hypokalemia, hypertension, and clinical signs of adrenal insufficiency. Mifepristone provides a valuable treatment option in patients with severe CS when surgery is unsuccessful or impossible.