Unilateral Adrenalectomy for Primary Bilateral Macronodular Adrenal Hyperplasia: Analysis of 71 Cases

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 Relationship Between Baseline Cortisol Levels and Surgery Method of Primary Bilateral Macronodular Adrenal Hyperplasia

Aim was to explore the associations between baseline cortisol levels and surgery method of primary bilateral macronodular adrenal hyperplasia (PBMAH). We retrospectively reviewed the clinical features and management of 30 patients (18 females and 12 males) who were diagnosed with PBMAH in our center between 2005 and 2019. Based on surgery method, we divided the patients into two groups: unilateral adrenalectomy (UA) group; and bilateral adrenalectomy (BA) group. Serum cortisol rhythm and 24-hour urinary free cortisol (UFC/24 h) levels were assayed using chemiluminescence method. Associations between baseline cortisol levels and BA were assessed using logistic regression. The predictive value of baseline cortisol levels for BA was calculated using receiver operating characteristic (ROC) curves. Twenty patients (66.7%) underwent UAs and ten patients (33.3%) underwent BAs. After adjusting for age, sex, BMI, SBP, and adrenal volume, the concentrations of baseline serum cortisol (8 AM, 4 PM, and 0 AM) and UFC/24 h were associated with bilateral adrenalectomy (all p<0.05). The area under the ROC curve based on 8 AM serum cortisol level model was larger than that in models based on 4 PM, 0 AM serum cortisol levels and UFC/24 h, but the differences were non-significant (all p>0.05). According to maximum Youden index criteria, the optimal cutoffs of 8 AM serum cortisol level and UFC were 26.89 μg/dl and 406.65 μg/24 h, respectively, for BA. The baseline cortisol levels are positively associated with BA. Increased levels of baseline cortisol levels may predict higher possibility of BA, which should be confirmed by prospective studies.

Identification of predictive criteria for pathogenic variants of primary bilateral macronodular adrenal hyperplasia (PBMAH) gene ARMC5 in 352 unselected patients

OBJECTIVE

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a heterogeneous disease characterized by adrenal macronodules and variable levels of cortisol excess, with not clearly established clinical diagnostic criteria. It can be caused by ARMC5 germline pathogenic variants. In this study, we aimed to identify predictive criteria for ARMC5 variants.

METHODS

We included 352 consecutive index patients from 12 European centers, sequenced for germline ARMC5 alteration. Clinical, biological and imaging data were collected retrospectively.

RESULTS

52 patients (14.8%) carried ARMC5 germline pathogenic variants and showed a more distinct phenotype than non-mutated patients for cortisol excess (24-h urinary free cortisol 2.32 vs 1.11-fold ULN, respectively, P < 0.001) and adrenal morphology (maximal adrenal diameter 104 vs 83 mm, respectively, P < 0.001) and were more often surgically or medically treated (67.9 vs 36.8%, respectively, P < 0.001). ARMC5-mutated patients showed a constant, bilateral adrenal involvement and at least a possible autonomous cortisol secretion (defined by a plasma cortisol after 1 mg dexamethasone suppression above 50 nmol/L), while these criteria were not systematic in WT patients (78.3%). The association of these two criteria holds a 100% sensitivity and a 100% negative predictive value for ARMC5 pathogenic variant.

CONCLUSION

We report the largest series of index patients investigated for ARMC5 and confirm that ARMC5 pathogenic variants are associated with a more severe phenotype in most cases. To minimize negative ARMC5 screening, genotyping should be limited to clear bilateral adrenal involvement and autonomous cortisol secretion, with an optimum sensitivity for routine clinical practice. These findings will also help to better define PBMAH diagnostic criteria.

Long delay in diagnosis of a case with MEN1 due to concomitant presence of AIMAH with insulinoma: a case report and literature review

BACKGROUND

ACTH-independent macronodular hyperplasia (AIMAH) is an uncommon disorder characterized by massive enlargement of both adrenal glands and hypersecretion of cortisol. Concomitant AIMAH and multiple endocrine neoplasia type1 (MEN1) is rare to our knowledge.

CASE PRESENTATION

Herein, we describe a 32 year old woman with long history of prolactinoma and secondary ammonhrea presented with not-severe manifestation of hypoglycemia due to concomitant presence of insulinoma with AIMAH leading to 12 years delay of MEN1 diagnosis. Laboratory tests showed severe hypoglycemia associated with hyper insulinemia (non-fasting blood sugar = 43 mg/dl, insulin = 80.6 μIU /ml, C-peptide = 9.3 ng/ml) hyperparathyroidism (calcium = 10.3 mg/dl, phosphor = 3.1 mg/dl, PTH = 280 pg/ml) and chemical evidence of an ACTH-independent hypercortisolism (serum cortisol value of 3.5, after 1 mg dexamethasone suppression test serum ACTH value of 17 pg/ml, and high urinary cortisol level). Abdominal CT scan demonstrated two enhancing well-defined masses 27*20 mm and 37*30 mm in the tail and body of the pancreas, respectively, and a 36*15 mm mass in left adrenal gland (seven Hounsfield units). Dynamic pituitary MRI revealed a partial empty sella. The physical examination of the patient was unremarkable. Distal pancreatectomy and a left adrenalectomy were performed. After the surgery, we observed clinical and biochemical remission of hyper insulinemia and gradual decrease in urinary cortisol. The histological features of the removed left adrenal gland were consistent with AIMAH. Histological examination of the pancreatic lesions revealed well differentiated neuroendocrine tumors. Genetic abnormalities in the MEN1, heterozygote for pathogenic variant chr11; 645,773,330-64577333AGAC, c.249-252delGTCT, p. (11e85Serfs Ter33) in exon 2 were found. It was recommended the patient undergoes parathyroidectomy as soon as possible.

CONCLUSION

Given the history and presentation of our case, we recommend that the clinicians consider the possibility of autonomous cortisol production in MEN1 patients who do not show severe symptoms of hypoglycemia in the presence of insulinoma.

Steroid profiling using liquid chromatography mass spectrometry during adrenal vein sampling in patients with primary bilateral macronodular adrenocortical hyperplasia

INTRODUCTION

Adrenal vein sampling (AVS) is not a routine procedure in patients with primary bilateral macronodular adrenocortical hyperplasia (PBMAH), but has been used to determine lateralization of cortisol secretion in order to guide decision of unilateral adrenalectomy. Our aim was to characterize the steroid fingerprints in AVS samples of patients with PBMAH and hypercortisolism and to identify a reference hormone for AVS interpretation.

METHOD

Retrospectively, we included 17 patients with PBMAH from the German Cushing's registry who underwent AVS. 15 steroids were quantified in AVS and peripheral blood samples using LC-MS/MS. We calculated lateralization indices and conversion ratios indicative of steroidogenic enzyme activity to elucidate differences between individual adrenal steroidomes and in steroidogenic pathways.

RESULTS

Adrenal volume was negatively correlated with peripheral cortisone (r=0.62, p<0.05). 24-hour urinary free cortisol correlated positively with peripheral androgens (rDHEA=0.57, rDHEAS=0.82, rA=0.73, rT=0.54, p<0.05). DHEA was found to be a powerful reference hormone with high selectivity index, which did not correlate with serume cortisol and has a short half-life. All investigated steroids showed lateralization in single patients indicating the heterogenous steroid secretion pattern in patients with PBMAH. The ratios of corticosterone/aldosterone (catalyzed by CYP11B2), androstenedione/dehydroepiandrosterone (catalyzed by HSD3B2) and cortisone/cortisol (catalyzed by HSD11B2) in adrenal vein samples were higher in smaller adrenals (p<0.05). ARMC5 mutation carriers (n=6) showed lower androstenedione/17-hydroxyprogesterone and higher testosterone/androstenedione (p<0.05) ratios in peripheral blood, in line with lower peripheral androstenedione concentrations (p<0.05).

CONCLUSION

Steroid profiling by LC-MS/MS led us to select DHEA as a candidate reference hormone for cortisol secretion. Lateralization and different steroid ratios showed that each steroid and all three steroidogenic pathways may be affected in PBMAH patients. In patients with germline ARMC5 mutations, the androgen pathway was particularly dysregulated.

Draft of the clinical practice guidelines “Adrenal incidentaloma”

The wider application and technical improvement of abdominal imaging procedures in recent years has led to an increasingly frequent detection of adrenal gland masses — adrenal incidentaloma, which have become a common clinical problem and need to be investigated for evidence of hormonal hypersecretion and/or malignancy. Clinical guidelines are the main working tool of a practicing physician. Laconic, structured information about a specific nosology, methods of its diagnosis and treatment, based on the principles of evidence-based medicine, make it possible to give answers to questions in a short time, to achieve maximum efficiency and personalization of treatment. These clinical guidelines include data on the prevalence, etiology, radiological features and assessment of hormonal status of adrenal incidentalomas. In addition, this clinical practice guideline provides information on indications for surgery, postoperative rehabilitation and follow-up.

Unilateral adrenalectomy partially improved hyperglycemia in a patient with primary bilateral macronodular adrenal hyperplasia

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is characterized by bilateral multiple adrenal macro-nodules that often cause mild over-secretion of cortisol in the form of subclinical Cushing's syndrome. We herein describe a case, wherein unilateral adrenalectomy partially improved hyperglycemia in a patient with PBMAH and suggest the usefulness and limitations of this surgical strategy. A 64-year-old woman with type 2 diabetes had an incidental diagnosis of bilateral adrenal lesions. She had a family history of type 2 diabetes, and her HbA1c level was 8.9% under insulin therapy. She did not present with any symptoms associated with Cushing's syndrome. The basal cortisol level was in the normal range (12.0 μg/dL); however, the adrenocorticotropic hormone (ACTH) level was suppressed (2.1 pg/mL) and the serum cortisol level was not suppressed in the dexamethasone test. Computed tomography and magnetic resonance imaging showed bilateral adrenal macro-nodules and ¹³¹I-adosterol accumulated in the bilateral adrenal lesions. Collectively, she was diagnosed with subclinical Cushing's syndrome due to PBMAH complicated with diabetes mellitus, hypertension, and dyslipidemia. Laparoscopic left adrenalectomy was performed, and the pathologic findings were consistent with PBMAH. After unilateral adrenalectomy, serum cortisol levels decreased, and hypertension improved. Both HbA1c levels and insulin requirement also decreased, but insulin therapy was continuously needed. It should be noted that hyperglycemia may not be cured after successful surgery in a patient with PBMAH. Additional operation or medical therapy should be considered if unilateral adrenalectomy is unable to correct hypercortisolism in PBMAH patients.

[Bilateral macronodular adrenal hyperplasia: a rare cause of Cushing's syndrome (a case report)]

Bilateral macronodular adrenal hyperplasia (BMAH) is a rare cause of adrenal Cushing's syndrome, accounting for less than 1% of cases. We here report the case of a 48-year-old patient with diabetes and hypertension presenting with clinical signs of Cushing's syndrome. Etiological assessment enabled clinicians to retain the diagnosis of Adrenocorticotropic hormone (ACTH)-independent hypercortisolism associated with BMAH. Unilateral left adrenalectomy was performed based on noriodocholesterol scintigraphy results, with good outcome. However, given the risk of recurrence and cardiovascular complications, long-term monitoring was scheduled.

Incidentally discovered myelolipomatous adrenal adenomas, including six cases presenting with hypercortisolism

Most adrenal incidentalomas are non-functioning adenomas that require no treatment. The presence of a myelolipomatous component of adrenal incidentalomas is a rare, but well-known occurrence in both hyperplastic and neoplastic lesions of the adrenal cortex. Although the improvements in abdominal imaging have increased identification of myelolipomatous adrenal cortical adenomas radiologically, due to the rarity of this lesion, the clinical pathological features of these lesions are unclear and can sometimes cause diagnostic difficulty. Eleven patients had surgeries at The University of Texas MD Anderson Cancer Center. Four additional cases were provided from an external collaborator. Of the 15 cases, there were 5 male and 10 female patients, with a median age of 52 years (mean 54 years, range 28-84 years). Clinical presentation included adrenal incidentaloma (n = 9), Cushing syndrome (n = 4, including 1 as a part of Carney complex), and subclinical Cushing syndrome (n = 2, including 1 with bilateral macronodular adrenal hyperplasia). In this study, we present the clinicopathologic features of fifteen myelolipomatous adrenal adenomas, the largest series published thus far.

Update on primary bilateral macronodular adrenal hyperplasia (PBMAH)

Primary bilateral macronodular adrenal hyperplasia (PBMAH), characterized by bilateral benign adrenal macronodules (>1 cm) potentially responsible for variable levels of cortisol excess, is a rare and heterogeneous disease. However, its frequency increases due to incidentally diagnosed cases on abdominal imaging carried out for reasons other than suspected adrenal disease. Mostly isolated, it can also be associated with dominantly inherited genetic conditions in rare cases. Considering the bilateral nature of adrenal involvement and the description of familial cases, the search of a genetic predisposition has led to the identification of germline heterozygous inactivating mutations of the putative tumor suppressor gene ARMC5, causing around 25% of the apparent sporadic cases. Rigorous biochemical and imaging assessment are key elements in the management of this challenging disease in terms of diagnosis. Treatment is reserved for symptomatic patients with overt or subclinical Cushing syndrome, and was historically based on bilateral adrenalectomy, which nowadays tends to be replaced by unilateral adrenalectomy or lifelong treatment with cortisol synthesis inhibitors.

Role of unilateral adrenalectomy in bilateral adrenal hyperplasias with Cushing's syndrome

Primary bilateral adrenocortical hyperplasias are rare forms of pituitary ACTH-independent Cushing's syndrome (CS). They are divided between primary bilateral macronodular adrenal hyperplasia (PBMAH) and micronodular adrenal hyperplasia (MiBAH), which is subdivided in primary pigmented nodular adrenocortical disease (PPNAD) and isolated micronodular adrenocortical disease (i-MAD). One of the most debated aspects surrounding these entities is their most appropriate therapy. Although bilateral adrenalectomy (BA) has previously been the most utilized therapy for patients with overt CS, recent studies have indicated that unilateral adrenalectomy (UA) can be effective in patients with PBMAH and some with MiBAH with fewer long-term side effects. Medical therapies can also be used for bridging to surgery or rarely in the long-term for these patients. We review the various degrees of CS resulting from PBMAH and MiBAH, with a special focus on their respective therapies including UA, taking into account the recent pathophysiological and genetics findings.

[Immunohistochemical study on the expression/hyperexpression of aberrant/eutopic receptors in patients with bilateral macronodular adrenal hyperplasia]

Bilateral macronodular adrenal hyperplasia (BMAH) is a rare cause of Cushing's syndrome. In this case cortisol production can be regulated by both genetic factors and various molecular mechanisms. The presence of aberrant or overexpression of eutopic receptors on the membrane of adrenal cortex may lead to activation of cAMP/PKA signaling pathways and consequently, pathological stimulation of steroidogenesis. Since proving the effectiveness of unilateral adrenalectomy in BMAH by achievement of stable remission, preoperative clinical and laboratory tests (ligand-induced tests) are no longer of relevant. Nevertheless, in the absence of normalization of the level of cortisol in the postoperative period or its recurrence, subsequent specific targeted medical options can be offered only if expression/hyperexpression predominance of one or another receptor. Their detection becomes possible using more reliable diagnostic methods such as polymerase chain reaction (PCR) and immunohistochemical studies (IHC) than clinical laboratory tests. At the moment, PCR has gained a wider application. This article summarizes data on the use of immunohistochemical study in BMAH.