Contralateral adrenal suppression on adrenocortical scintigraphy provides good evidence showing subclinical cortisol overproduction from unilateral adenomas

Clinical, pathophysiologic, genetic and therapeutic progress in Primary Bilateral Macronodular Adrenal Hyperplasia

Patients with primary bilateral macronodular adrenal hyperplasia (PBMAH) usually present bilateral benign adrenocortical macronodules at imaging and variable levels of cortisol excess. PBMAH is a rare cause of primary overt Cushing's syndrome, but may represent up to one third of bilateral adrenal incidentalomas with evidence of cortisol excess. The increased steroidogenesis in PBMAH is often regulated by various G-protein coupled receptors aberrantly expressed in PBMAH tissues; some receptor ligands are ectopically produced in PBMAH tissues creating aberrant autocrine/paracrine regulation of steroidogenesis. The bilateral nature of PBMAH and familial aggregation, led to the identification of germline heterozygous inactivating mutations of the ARMC5 gene, in 20-25% of the apparent sporadic cases and more frequently in familial cases; ARMC5 mutations/pathogenic variants can be associated with meningiomas. More recently, combined germline mutations/pathogenic variants and somatic events inactivating the KDM1A gene were specifically identified in patients affected by GIP-dependent PBMAH. Functional studies demonstrated that inactivation of KDM1A leads to GIP-receptor (GIPR) overexpression and over or down-regulation of other GPCRs. Genetic analysis is now available for early detection of family members of index cases with PBMAH carrying identified germline pathogenic variants. Detailed biochemical, imaging, and co-morbidities assessment of the nature and severity of PBMAH is essential for its management. Treatment is reserved for patients with overt or mild cortisol/aldosterone or other steroid excesses taking in account co-morbidities. It previously relied on bilateral adrenalectomy; however recent studies tend to favor unilateral adrenalectomy, or less frequently, medical treatment with cortisol synthesis inhibitors or specific blockers of aberrant GPCR.

The role of adrenal venous sampling (AVS) in primary bilateral macronodular adrenocortical hyperplasia (PBMAH): a study of 16 patients

OBJECTIVE

Primary bilateral macronodular adrenocortical hyperplasia (PBMAH) is a rare cause of ACTH-independent Cushing's syndrome. Current guidelines recommend bilateral adrenalectomy for PBMAH, but several studies showed clinical effectiveness of unilateral adrenalectomy despite bilateral disease in selected patients. Our aim was to evaluate the gain of information which can be obtained through adrenal venous sampling (AVS) based cortisol lateralization ratios for guidance of unilateral adrenalectomy.

DESIGN

We performed a retrospective analysis of 16 patients with PBMAH and clinical overt cortisol secretion in three centers METHODS: Selectivity of adrenal vein sampling during AVS was defined as a gradient of cortisol or a reference adrenal hormone ≥2.0 between adrenal and peripheral vein. Lateralization was assumed if the dominant to non-dominant ratio of cortisol to reference hormone was ≥4.0.

RESULTS

AVS was technically successful in all patients based on absolute cortisol levels and in 13 of 16 patients (81%) based on reference hormone levels. Lateralization was documented in 8 of 16 patients. In patients with lateralization, in 5 of 8 cases this occurred toward morphologically larger adrenals, while in 3 patients lateralization was present in bilaterally identical adrenals. The combined volume of adrenals correlated positively with urinary free cortisol, suggesting that adrenal size is the dominant determinant of cortisol secretion.

CONCLUSIONS

In this study the gain of information through AVS for unilateral adrenalectomy was limited in patients with PBMAH and marked adrenal asymmetry.

The association between adrenal adenoma size, autonomous cortisol secretion and metabolic derangements

OBJECTIVE

Autonomous cortisol secretion (ACS) is common in patients with adrenal incidentalomas (AI). ACS is associated with increased cardiovascular morbidity and mortality. Data regarding the association between radiological characteristics of adrenal adenomas, their hormonal functionality and metabolic outcomes, are scarce and inconclusive. In this study, we aim to delineate the association between radiological characteristics of AI, ACS and metabolic status.

METHODS

A cross-sectional study of 77 patients with AI who underwent a comprehensive hormonal evaluation. Radiological assessments were performed by an independent radiologist blinded to the clinical and hormonal phenotype of each case. Linear regression models were used to evaluate the association between post dexamethasone suppression test (DST) cortisol levels, metabolic indices and radiological measurements.

RESULTS

Mean maximal adenoma diameter was greater in patients with versus without ACS (20.35 ± 6 vs. 27.09 ± 9.3 mm, respectively, p < .01). Maximal adenoma diameter was found to be positively and linearly correlated with post-DST morning cortisol levels across their entire range (R = .474, p < .01). Linear correlations between maximal adenoma diameter and indices of glycemic control showed a correlation coefficient (R) of .481 and .463 for fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c), respectively, p < .01. When analysis included only patients with ACS, an R = .584 and R = .565 was observed for FPG and HbA1c, respectively (p < .01 for both). The association between maximal adenoma diameter and both FPG and post-DST morning cortisol intensified in patients with metabolic syndrome.

CONCLUSION

There is a quantitative positive mild correlation between AI size and both cortisol autonomy and metabolic parameters.

Investigation of Cushing's and subclinical Cushing's syndromes using adrenocortical scintigraphy

OBJECTIVES

This study assessed the factors related to the intake rate of adrenocortical scintigraphy in Cushing's and subclinical Cushing's syndromes, in addition to the methods for differentiating between the two.

METHODS

Clinical findings, blood sampling, and adrenocortical scintigraphy collected at St. Marianna University School of Medicine from 1 January 2010 to 31 December 2019 were used to diagnose initial-onset Cushing's syndrome and subclinical Cushing's syndrome, and patients who underwent 131I-NP-59 adrenocortical scintigraphy were used as study subjects.

RESULTS

A total of 24 (8 male and 16 female) patients were selected. Of them, 7 had Cushing's syndrome and 17 had subclinical Cushing's syndrome. A correlation coefficient of -0.474 (P = 0.026) was determined between the intake rate after 7 days and adrenocorticotropic hormone levels. Intake rates after 5 days were 0.51% and 0.31% for Cushing's and subclinical Cushing's syndromes, respectively, and were statistically significant (P = 0.03). Intake rates after 7 days were 0.47% and 0.30% for Cushing's and subclinical Cushing's syndromes, respectively, and were statistically significant (P = 0.04). Receiver operating characteristic analysis results of Cushing's and subclinical Cushing's syndromes for intake rates after 7 days were as follows: cutoff value, 0.248; area under curve, 0.769; and 95% confidence interval, 0.561-0.977.

CONCLUSION

There were differences in the intake rates of adrenocortical scintigraphy between the Cushing's syndrome group and subclinical Cushing's syndrome group, making it possible to differentiate between the two using the intake rate.

Approach to the Patient with Subclinical Cushing's Syndrome

A growing number of patients with adrenal incidentalomas and subclinical Cushing's syndrome (SCS) led to an increasing number of different guidelines, and diagnostic and treatment recommendations. Excess cortisol secretion in patients with SCS is associated with several comorbidities, such as hypertension, dyslipidemia, type 2 diabetes mellitus, and obesity, which in the long-term increase mortality of these patients. Subtle cortisol secretion affects bone health, quality of life and causes depression, but due to the unapparent clinical features, patients with SCS are often at risk between over and under treatment. This narrative review aimed to summarize the latest recommendations on the approach to the patient with subclinical Cushing's syndrome.

Adrenal Vein Cortisol to Metanephrine Ratio for Localizing ACTH-Independent Cortisol-Producing Adenoma: A Case Report

Context

Finding the source of adrenocorticotropic hormone (ACTH)-independent cortisol-producing adenoma in the patients with subclinical Cushing syndrome (SCS) and bilateral adrenal nodules is sometimes challenging. Computed tomography (CT) and positron emission tomography are helpful, but adrenal venous sampling (AVS) is the gold standard approach. However, interpretation of AVS is important to improve the accuracy of decision-making for surgery. We report a case and review of the literature to assess the benefit of using adrenal vein cortisol to metanephrine ratio to determine the source of cortisol production in SCS and bilateral nodules.

Evidence Acquisition

Three authors searched PubMed for data on patients with SCS who had AVS procedure and measurements of cortisol and catecholamines.

Case Description

A 51-year-old woman with SCS and hypertension crisis presented to our clinic. Paraclinical investigations revealed that she had an ACTH-independent cortisol-producing adenoma and her CT scan showed bilateral adrenal nodules. After AVS, cortisol (high to low) lateralization ratio could not determine the source of cortisol production but the cortisol to metanephrine ratio localized the source to the left side, which included the larger nodule according to CT measurements. Left adrenalectomy led to clinical and paraclinical improvement.

Conclusion

There is a possibility of co-secretion of other steroids accompanied with cortisol in the setting of ACTH-independent SCS. Moreover, cortisol measurement alone and interpretation of AVS results based on cortisol values may not help lateralizing the source of cortisol production with bilateral adrenal nodules. Therefore, we suggest applying cortisol to metanephrine ratio with the same gradient (gradient > 2.3, highest to lowest concentration) when the source of cortisol production cannot be determined by cortisol lateralization ratio.

Application of adrenal maximum standardized uptake value to 131I-6β-iodomethyl-19-norcholesterol SPECT/CT for characterizing unilateral hyperfunctioning adrenocortical masses

PURPOSE

To evaluate the maximum standardized uptake value (SUVmax) by ¹³¹I-6β-iodomethyl-19-norcholesterol (NP-59) single-photon emission computed tomography (SPECT)/computed tomography (CT) for characterizing unilateral hyperfunctioning adrenocortical masses.

METHODS

Ten patients underwent NP-59 SPECT/CT to evaluate the following unilateral adrenocortical hyperfuncting masses: three with Cushing's syndrome (CS), three with subclinical CS, and four with primary aldosteronism (PA). Visual and quantitative or semiquantitative analyses (noncontrast CT HU [Hounsfield units], lesion SUVmax, contralateral SUVmax, and SUVmax ratio [lesion SUVmax/contralateral adrenal SUVmax]) were performed. The Mann-Whitney U test or Chi-squared test was used appropriately to assess differences between quantitative variables or compare categorical data. Diagnostic performance was evaluated by receiver operating characteristic (ROC) curve analysis.

RESULTS

All adrenal tumors were diagnosed as cortical adenomas. On visual analysis, unilateral uptake was noted in three patients with CS and one patient with subclinical CS, whereas bilateral uptake was noted in four patients with PA and two patients with subclinical CS (p = 0.046). No significant difference was observed in CT HU (p = 0.055). The lesion SUVmax and SUVmax ratio were significantly higher and the contralateral SUVmax was significantly lower in six patients with CS than in four patients with PA (each, p < 0.05). The area under the ROC curve and accuracy for differentiating between CS and PA were, respectively, 0.92 and 90.0 % for the lesion SUVmax, 1.00 and 100 % for the contralateral SUVmax, and 0.92 and 90.0 % for the SUVmax ratio.

CONCLUSIONS

Quantitative or semiquantitative analysis using the adrenal SUVmax in adrenocortical NP-59 SPECT/CT has potential for characterizing unilateral hyperfunctioning adrenocortical masses.

Cardiac Myxoma Caused by Fumarate Hydratase Gene Deletion in Patient With Cortisol-Secreting Adrenocortical Adenoma

CONTEXT

Germline mutations in fumarate hydratase (FH) gene are known to cause hereditary leiomyomatosis and renal cell carcinoma (HLRCC) and are occasionally accompanied with cutaneous and uterine leiomyoma or cortisol-producing adrenocortical hyperplasia. However, the association between FH mutations and cardiac or adrenocortical tumors has remained unknown. Here, we identified a novel deletion in FH, exhibiting cardiac myxoma and subclinical Cushing syndrome due to adrenocortical tumor.

CASE DESCRIPTION

A 44-year-old man was referred to our hospital for cardiac and adrenal tumor evaluation. He had a history of multiple painful, dermal papules and nodules diagnosed as cutaneous leiomyoma. The surgically resected cardiac tumor was diagnosed as myxoma. The adrenal tumor was clinically diagnosed as subclinical Cushing syndrome. Laparoscopically resected adrenal tumor was pathologically diagnosed as adrenocortical adenoma harboring unique histological findings similar to primary pigmented nodular adrenocortical disease (PPNAD). DNA analysis revealed a germline deletion in FH c0.737delT (p. Phe225Leufs*31) and loss of heterozygosity (LOH) in cardiac myxoma. As a functional analysis of FH in cardiac myxoma, low FH protein expression with elevated 2-succinocysteine (2SC), a marker of FH dysfunction, was immunohistochemically detected. However, in adrenocortical tumor, LOH of FH was not detected, and FH or 2SC expression was not altered.

CONCLUSIONS

This is the first case of HLRCC complicated by cardiac myxoma. LOH of FH deletion and its dysfunction were identified in cardiac myxoma. The association between FH deletion and adrenocortical lesion, however, needs to be further clarified.

Remitting seronegative symmetrical synovitis with pitting oedema after surgical remission of Cushing's syndrome

A 64-year-old woman with refractory cellulitis in the lower legs was referred for inadequate glycaemic control. Physical examination revealed cushingoid features including central obesity. CT of the abdomen revealed a right adrenal mass that was positive on ¹³¹I-adosterol imaging. Findings on endocrine evaluation confirmed a diagnosis of Cushing's syndrome, which was cured with a right adrenalectomy. Two months after surgery, the patient complained of pain and marked swelling of the hands during hydrocortisone replacement therapy (20 mg per day) given for postoperative adrenal insufficiency. Laboratory examination was unremarkable. However, contrast-enhanced T2-weighted MRI of the hands revealed enhanced signals surrounding the flexor tendons, leading to a diagnosis of remitting seronegative symmetrical synovitis with pitting oedema. Prednisolone (15 mg per day) was then initiated, and the symptoms disappeared within a few days. This case illustrates the possibility that successful treatment of Cushing's syndrome may trigger emergence of a glucocorticoid-responsive disease.

Adrenal Imaging in Patients with Endocrine Hypertension

Hypertension is one of the commonest chronic diseases contributing to cardiovascular disease. Idiopathic (primary) hypertension accounts for approximately 85% of the diagnosed cases, and 15% of hypertensive patients have other contributing conditions leading to elevated blood pressure (secondary hypertension). Endocrine hypertension is a common secondary cause of hypertension. The most common causes of endocrine hypertension are excess production of mineralocorticoids (ie, primary hyperaldosteronism), glucocorticoids (Cushing syndrome), and catecholamines (pheochromocytoma). After biochemical confirmation of hormonal excess, appropriate use of imaging modalities, both functional and anatomic, should occur for the diagnostic workup of these patients and for location of the source of hormonal excess.

Modern Management of Mild Autonomous Cortisol Secretion

Incidentally discovered adrenal tumors are reported in ~ 5% of adults undergoing cross-sectional imaging. Mild autonomous cortisol secretion (MACS) from the adrenal mass is demonstrated in 5-48% of patients with adrenal tumors. The diagnosis of MACS represents a challenge due to limitations of the currently used diagnostic tests, differences in the definitions of the clinically relevant MACS, and heterogeneity in an individual's susceptibility to abnormal cortisol secretion from the adrenal mass. Patients with MACS present with increased risk of cardiovascular risk factors, cardiovascular events, metabolic bone disease, and mortality. Adrenalectomy improves or reverses MACS-associated comorbidities in selected patients. The current review will address diagnostic and management challenges in the care of patients with MACS, discuss data on emerging biomarkers, and suggest future directions in the field of MACS.

Adrenal Venous Sampling for Assessment of Autonomous Cortisol Secretion

CONTEXT

Autonomous cortisol secretion (ACS) can be unilateral or bilateral irrespective of the presence of an adrenal tumor. A reliable method to distinguish between unilateral and bilateral ACS is lacking.

OBJECTIVE

Evaluate the use of adrenal venous sampling (AVS) to distinguish between unilateral and bilateral ACS.

DESIGN AND METHODS

This was a prospective study of AVS in patients with adrenal tumors who received a diagnosis of ACS or adrenal Cushing syndrome (CS). Unilateral secretion was defined as >2.3-fold difference in cortisol levels between the two adrenal veins. Metanephrine levels were used to ascertain correct catheter position. Results were correlated with findings on CT and iodine-131-cholesterol scintigraphy.

RESULTS

Thirty-nine patients underwent AVS; there were no complications. The procedure was inconclusive in six patients and repeated with success in one, giving a success rate of 85%, and leaving 34 procedures for evaluation (adrenal CS, n = 2; ACS, n = 32). Of 14 patients with bilateral tumors, 10 had bilateral and 4 had unilateral overproduction. Of 20 patients with unilateral tumors, 11 had lateralization to the side of the tumor and the remaining had bilateral secretion. Cholesterol scintigraphy findings were concordant with those of AVS in 13 of 18 cases (72%) and discordant in 5 (28%).

CONCLUSION

Laterality of ACS does not always correspond to findings on CT images. AVS is a safe and valuable tool for differentiation between unilateral and bilateral cortisol secretion and should be considered when operative treatment of ACS is a possibility.

New diagnostic criteria of adrenal subclinical Cushing's syndrome: opinion from the Japan Endocrine Society

New diagnostic criteria and the treatment policy for adrenal subclinical Cushing's syndrome (SCS) are proposed on behalf of the Japan Endocrine Society. The Japanese version has been published, and the essential contents are presented in this English-language version. The current diagnostic criteria for SCS have elicited two main problems: (i) the relatively low reliability of a low range of serum cortisol essential for the diagnosis by an overnight 1-mg dexamethasone suppression test (DST); (ii) different cutoff values for serum cortisol after a 1-mg DST compared with those of other countries. Thus, new criteria are needed. In the new criteria, three hierarchical cortisol cutoff values, 5.0, 3.0 and 1.8 μg/dL, after a 1-mg DST are presented. Serum cortisol ≥5 μg/dL after a 1-mg DST alone is considered sufficient to judge autonomous cortisol secretion for the diagnosis of SCS, and the current criterion based on serum cortisol ≥3 μg/dL after a 1-mg DST can continue to be used. Clinical evidence suggests that serum cortisol ≥1.8-2.9 μg/dL after a 1-mg DST is not always normal, so cases who meet the cutoff value as well as a basal adrenocorticotropic hormone (ACTH) level <10 pg/mL (or poor ACTH response to corticotropin-releasing hormone (CRH)) and nocturnal serum cortisol ≥5 μg/dL are proposed to have SCS. We suggest surgery if cases show serum cortisol ≥5 μg/dL after a 1-mg DST (or are disheartened by treatment-resistant problems) or suspicious cases of adrenal cancer according to tumor imaging.