Inactivation of the APC gene is constant in adrenocortical tumors from patients with familial adenomatous polyposis but not frequent in sporadic adrenocortical cancers

Consensus statement by the French Society of Endocrinology (SFE) and French Society of Pediatric Endocrinology & Diabetology (SFEDP) for the diagnosis of Cushing's syndrome: Genetics of Cushing's syndrome

Cushing's syndrome is due to overproduction of cortisol, leading to abnormal and prolonged exposure to cortisol. The most common etiology is Cushing disease, while adrenal causes are rarer. Knowledge of the genetics of Cushing's syndrome, and particularly the adrenal causes, has improved considerably over the last 10 years, thanks in particular to technical advances in high-throughput sequencing. The present study, by a group of experts from the French Society of Endocrinology and the French Society of Pediatric Endocrinology and Diabetology, reviewed the literature on germline genetic alterations leading to a predisposition to develop Cushing's syndrome. The review led to a consensus statement on genetic screening for Cushing disease and adrenal Cushing's syndrome.

Current prospects of hereditary adrenal tumors: towards better clinical management

Adrenocortical carcinoma (ACC) and pheochromocytoma/paraganglioma (PPGL) are two rare types of adrenal gland malignancies. Regarding hereditary tumors, some patients with ACC are associated with with Li-Fraumeni syndrome (LFS), and those with PPGL with multiple endocrine neoplasia type 2. Recent studies have expanded this spectrum to include other types of hereditary tumors, such as Lynch syndrome or familial adenomatous polyposis. Individuals harboring germline TP53 pathogenic variants that cause LFS have heterogeneous phenotypes depending on the respective variant type. As an example, R337H variant found in Brazilian is known as low penetrant. While 50-80% of pediatric ACC patients harbored a LFS, such a strong causal relationship is not observed in adult patients, which suggests different pathophysiologies between the two populations. As for PPGL, because multiple driver genes, such as succinate dehydrogenase (SDH)-related genes, RET, NF1, and VHL have been identified, universal multi-gene germline panel testing is warranted as a comprehensive and cost-effective approach. PPGL pathogenesis is divided into three molecular pathways (pseudohypoxia, Wnt signaling, and kinase signaling), and this classification is expected to result in personalized medicine based on genomic profiles. It remains unknown whether clinical characteristics differ between cases derived from genetic predisposition syndromes and sporadic cases, or whether the surveillance strategy should be changed depending on the genetic background or whether it should be uniform. Close cooperation among medical genomics experts, endocrinologists, oncologists, and early investigators is indispensable for improving the clinical management for multifaceted ACC and PPGL.

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.

Primary bilateral macronodular adrenal hyperplasia: definitely a genetic disease

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is an adrenal cause of Cushing syndrome. Nowadays, a PBMAH diagnosis is more frequent than previously, as a result of progress in the diagnostic methods for adrenal incidentalomas, which are widely available. Although some rare syndromic forms of PBMAH are known to be of genetic origin, non-syndromic forms of PBMAH have only been recognized as a genetic disease in the past 10 years. Genomics studies have highlighted the molecular heterogeneity of PBMAH and identified molecular subgroups, allowing improved understanding of the clinical heterogeneity of this disease. Furthermore, the generation of these subgroups permitted the identification of new genes responsible for PBMAH. Constitutive inactivating variants in ARMC5 and KDM1A are responsible for the development of distinct forms of PBMAH. To date, pathogenic variants of ARMC5 are responsible for 20-25% of PBMAH, whereas germline KDM1A alterations have been identified in >90% of PBMAH causing food-dependent Cushing syndrome. The identification of pathogenic variants in ARMC5 and KDM1A demonstrated that PBMAH, despite mostly being diagnosed in adults aged 45-60 years, is a genetic disorder. This Review summarizes the important progress made in the past 10 years in understanding the genetics of PBMAH, which have led to a better understanding of the pathophysiology, opening new clinical perspectives.

Identification of APC Mutation as a Potential Predictor for Immunotherapy in Colorectal Cancer

To date, anticancer immunotherapy has presented some clinical benefits to most of advanced mismatch repair deficient (dMMR)/microsatellite instability-high (MSI-H) colorectal cancer (CRC) patients. In addition to MSI status, we aimed to reveal the potential predictive value of adenomatous polyposis coli (APC) gene mutations in CRC patients. A total of 238 Chinese CRC patients was retrospectively identified and analyzed for clinical features and gene alternations in APC-mutant type (MT) and APC-wild-type (WT) groups. Clinical responses were then evaluated from the public TCGA database and MSKCC immunotherapy database. Although programmed cell death ligand 1 (PD-L1) level, MSI status, loss of heterogeneity at the human leukocyte antigen (HLA LOH), and tumor neoantigen burden (TNB) level were not statistically different between the APC-MT group and APC-WT group, tumor mutation burden (TMB) level was significantly higher in APC-MT patients (P < 0.05). Furthermore, comutation analysis for APC mutations revealed co-occurring genomic alterations of PCDHB7 and exclusive mutations of CTNNB1, BRAF, AFF3, and SNX25 (P < 0.05). Besides, overall survival from MSKCC-CRC cohort was longer in the APC-WT group than in the APC-MT group (HR 2.26 (95% CI 1.05–4.88), P < 0.05). Furthermore, most of patients in the APC-WT group were detected as high-grade immune subtypes (C2–C4) comparing with those in the APC-MT group. In addition, the percentages of NK T cells, Treg cells, and fibroblasts cells were higher in APC-WT patients than in APC-MT patients (P < 0.05). In summary, APC mutations might be associated with poor outcomes for immunotherapy in CRC patients regardless of MSI status. This study suggested APC gene mutations might be a potential predictor for immunotherapy in CRC.

Genetic Alterations in Benign Adrenal Tumors

The genetic basis of most types of adrenal adenomas has been elucidated over the past decade, leading to the association of adrenal gland pathologies with specific molecular defects. Various genetic studies have established links between variants affecting the protein kinase A (PKA) signaling pathway and benign cortisol-producing adrenal lesions. Specifically, genetic alterations in GNAS, PRKAR1A, PRKACA, PRKACB, PDE11A, and PDE8B have been identified. The PKA signaling pathway was initially implicated in the pathogenesis of Cushing syndrome in studies aiming to understand the underlying genetic defects of the rare tumor predisposition syndromes, Carney complex, and McCune-Albright syndrome, both affected by the same pathway. In addition, germline variants in ARMC5 have been identified as a cause of primary bilateral macronodular adrenal hyperplasia. On the other hand, primary aldosteronism can be subclassified into aldosterone-producing adenomas and bilateral idiopathic hyperaldosteronism. Various genes have been reported as causative for benign aldosterone-producing adrenal lesions, including KCNJ5, CACNA1D, CACNA1H, CLCN2, ATP1A1, and ATP2B3. The majority of them encode ion channels or pumps, and genetic alterations lead to ion transport impairment and cell membrane depolarization which further increase aldosterone synthase transcription and aldosterone overproduction though activation of voltage-gated calcium channels and intracellular calcium signaling. In this work, we provide an overview of the genetic causes of benign adrenal tumors.

A Comprehensive Investigation of Steroidogenic Signaling in Classical and New Experimental Cell Models of Adrenocortical Carcinoma

Adrenocortical carcinoma is a heterogeneous and aggressive cancer that originates from steroidogenic cells within the adrenal cortex. In this study, we have assessed for the preclinical gold standard NCI-H295 in direct comparison with the more recently established MUC-1 and a here newly reported ACC cell line (TVBF-7) the mutational status of important driver genes (TP53, MEN1, PRKAR1A, CTNNB1, APC, ZNRF-3, IGF-2, EGFR, RB1, BRCA1, BRCA2, RET, GNAS and PTEN), Wnt-signaling specificities (CTNNB1 mutation vs. APC mutation vs. wildtype), steroidogenic-(CYP11A1, CYP17A1, HSD3B2, HSD17B4, CYP21A2, CYP11B1, CYP11B2, MC2R, AT1R) and nuclear-receptor-signaling (AR, ER, GCR), varying electrophysiological potentials as well as highly individual hormone secretion profiles (Cortisol, Aldosterone, DHEA, DHEAS, Testosterone, 17-OH Progesterone, among others) which were investigated under basal and stimulated conditions (ACTH, AngII, FSK). Our findings reveal important genetic and pathophysiological characteristics for these three cell lines and reveal the importance of such cell-line panels reflecting differential endocrine functionalities to thereby better reflect clinically well-known ACC patient heterogeneities in preclinical studies.

An Overview of the Heterogeneous Causes of Cushing’s Syndrome due to Primary Macronodular Adrenal Hyperplasia (PMAH)

Primary macronodular adrenal hyperplasia (PMAH) is considered a rare cause of adrenal Cushing syndrome, is pituitary ACTH-independent, generally results from bilateral adrenal macronodules (>1 cm), and is often associated with variable cortisol secretion, resulting in a heterogeneous clinical presentation. Recent advances in the molecular pathogenesis of PMAH have offered new insights into the comprehension of this heterogeneous and complex adrenal disorder. Different molecular mechanisms involving the actors of the cAMP/protein kinase A pathway have been implicated in the development of PMAH, including germline and/or somatic molecular defects such as hyperexpression of the G-protein aberrant receptors and pathogenic variants of MC2R, GNAS, PRKAR1A, and PDE11A. Nevertheless, since 2013, the ARMC5 gene is believed to be a major genetic cause of PMAH, accounting for more than 80% of the familial forms of PMAH and 30% of apparently sporadic cases, except in food-dependent Cushing syndrome in which ARMC5 is not involved. Recently, 2 independent groups have identified that the tumor suppressor gene KDM1A is responsible for PMAH associated specifically with food-dependent Cushing syndrome. Consequently, PMAH has been more frequently genetically associated than previously assumed. This review summarizes the most important aspects, including hormone secretion, clinical presentation, radiological imaging, and molecular mechanisms, involved in familial Cushing syndrome associated with PMAH.

Overview of the 2022 WHO Classification of Adrenal Cortical Tumors

The new WHO classification of adrenal cortical proliferations reflects translational advances in the fields of endocrine pathology, oncology and molecular biology. By adopting a question-answer framework, this review highlights advances in knowledge of histological features, ancillary studies, and associated genetic findings that increase the understanding of the adrenal cortex pathologies that are now reflected in the 2022 WHO classification. The pathological correlates of adrenal cortical proliferations include diffuse adrenal cortical hyperplasia, adrenal cortical nodular disease, adrenal cortical adenomas and adrenal cortical carcinomas. Understanding germline susceptibility and the clonal-neoplastic nature of individual adrenal cortical nodules in primary bilateral macronodular adrenal cortical disease, and recognition of the clonal-neoplastic nature of incidentally discovered non-functional subcentimeter benign adrenal cortical nodules has led to redefining the spectrum of adrenal cortical nodular disease. As a consequence, the most significant nomenclature change in the field of adrenal cortical pathology involves the refined classification of adrenal cortical nodular disease which now includes (a) sporadic nodular adrenocortical disease, (b) bilateral micronodular adrenal cortical disease, and (c) bilateral macronodular adrenal cortical disease (formerly known primary bilateral macronodular adrenal cortical hyperplasia). This group of clinicopathological entities are reflected in functional adrenal cortical pathologies. Aldosterone producing cortical lesions can be unifocal or multifocal, and may be bilateral with no imaging-detected nodule(s). Furthermore, not all grossly or radiologically identified adrenal cortical lesions may be the source of aldosterone excess. For this reason, the new WHO classification endorses the nomenclature of the HISTALDO classification which uses CYP11B2 immunohistochemistry to identify functional sites of aldosterone production to help predict the risk of bilateral disease in primary aldosteronism. Adrenal cortical carcinomas are subtyped based on their morphological features to include conventional, oncocytic, myxoid, and sarcomatoid subtypes. Although the classic histopathologic criteria for diagnosing adrenal cortical carcinomas have not changed, the 2022 WHO classification underscores the diagnostic and prognostic impact of angioinvasion (vascular invasion) in these tumors. Microscopic angioinvasion is defined as tumor cells invading through a vessel wall and forming a thrombus/fibrin-tumor complex or intravascular tumor cells admixed with platelet thrombus/fibrin. In addition to well-established Weiss and modified Weiss scoring systems, the new WHO classification also expands on the use of other multiparameter diagnostic algorithms (reticulin algorithm, Lin-Weiss-Bisceglia system, and Helsinki scoring system) to assist the workup of adrenal cortical neoplasms in adults. Accordingly, conventional carcinomas can be assessed using all multiparameter diagnostic schemes, whereas oncocytic neoplasms can be assessed using the Lin-Weiss-Bisceglia system, reticulin algorithm and Helsinki scoring system. Pediatric adrenal cortical neoplasms are assessed using the Wieneke system. Most adult adrenal cortical carcinomas show > 5 mitoses per 10 mm² and > 5% Ki67. The 2022 WHO classification places an emphasis on an accurate assessment of tumor proliferation rate using both the mitotic count (mitoses per 10 mm²) and Ki67 labeling index which play an essential role in the dynamic risk stratification of affected patients. Low grade carcinomas have mitotic rate of ≤ 20 mitoses per 10 mm², whereas high-grade carcinomas show > 20 mitoses per 10 mm². Ki67-based tumor grading has not been endorsed in the new WHO classification, since the proliferation indices are continuous variables rather than being static thresholds in tumor biology. This new WHO classification emphasizes the role of diagnostic and predictive biomarkers in the workup of adrenal cortical neoplasms. Confirmation of the adrenal cortical origin of a tumor remains a critical requirement when dealing with non-functional lesions in the adrenal gland which may be mistaken for a primary adrenal cortical neoplasm. While SF1 is the most reliable biomarker in the confirmation of adrenal cortical origin, paranuclear IGF2 expression is a useful biomarker in the distinction of malignancy in adrenal cortical neoplasms. In addition to adrenal myelolipoma, the new classification of adrenal cortical tumors has introduced new sections including adrenal ectopia, based on the potential role of such ectopic tissue as a possible source of neoplastic proliferations as well as a potential mimicker of metastatic disease. Adrenal cysts are also discussed in the new classification as they may simulate primary cystic adrenal neoplasms or even adrenal cortical carcinomas in the setting of an adrenal pseudocyst.

Suppression of colorectal carcinogenesis by naringin

BACKGROUND

Colorectal cancer is the third most malignant cancer worldwide. Despite novel treatment options, the incidence and mortality rates of colon cancer continue to increase in most countries, especially in US, European and Asian countries. Colorectal carcinogenesis is multifactorial, including dietary and genetic factors, as well as lacking physical activity. Vegetables and fruits contain high amounts of secondary metabolites, which might reduce the risk for colorectal carcinogenesis. Flavonoids are important bioactive polyphenolic compounds. There are more than 4,000 different flavonoids, including flavanones, flavonoids, isoflavonoids, flavones, and catechins in a large variety of plant.

HYPOTHESIS

Among various other flavonoids, naringin in Citrus fruits has been a subject of intense scrutiny for its activity against many types of cancer, including colorectal cancer. We hypothesize that naringin is capable to inhibit the growth of transformed colonocytes and to induce programmed cell death in colon cancer cells.

RESULTS

We comprehensively review the inhibitory effects of naringin on colorectal cancers and address the underlying mechanistic pathways such as NF-κB/IL-6/STAT3, PI3K/AKT/mTOR, apoptosis, NF-κB-COX-2-iNOS, and β-catenin pathways.

CONCLUSION

Naringin suppresses colorectal inflammation and carcinogenesis by various signaling pathways. Randomized clinical trials are needed to determine their effectiveness in combating colorectal cancer.

Pediatric adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy of the adrenal gland with an unfavorable prognosis. It is rare in the pediatric population, with an incidence of 0.2-0.3 patients per million in patients under 20 years old. It is primarily associated with Li-Fraumeni and Beckwith-Wiedemann tumor predisposition syndromes in children. The incidence of pediatric ACC is 10-15fold higher in southern Brazil due to a higher prevalence of TP53 mutation associated with Li-Fraumeni syndrome in that population. Current treatment protocols are derived from adult ACC and consist of surgery and/or chemotherapy with etoposide, doxorubicin, and cisplatin (EDP) with mitotane. Limited research has been reported on other treatment modalities for pediatric ACC, including mitotane, pembrolizumab, cabozantinib, and chimeric antigen receptor autologous cell (CAR-T) therapy.

Bilateral Adrenal Hyperplasia: Pathogenesis and Treatment

Bilateral adrenal hyperplasia is a rare cause of Cushing’s syndrome. Micronodular adrenal hyperplasia, including the primary pigmented micronodular adrenal dysplasia (PPNAD) and the isolated micronodular adrenal hyperplasia (iMAD), can be distinguished from the primary bilateral macronodular adrenal hyperplasia (PBMAH) according to the size of the nodules. They both lead to overt or subclinical CS. In the latter case, PPNAD is usually diagnosed after a systematic screening in patients presenting with Carney complex, while for PBMAH, the diagnosis is often incidental on imaging. Identification of causal genes and genetic counseling also help in the diagnoses. This review discusses the last decades’ findings on genetic and molecular causes of bilateral adrenal hyperplasia, including the several mechanisms altering the PKA pathway, the recent discovery of ARMC5, and the role of the adrenal paracrine regulation. Finally, the treatment of bilateral adrenal hyperplasia will be discussed, focusing on current data on unilateral adrenalectomy.

A novel nonsense mutation in ARMC5 causes primary bilateral macronodular adrenocortical hyperplasia

BACKGROUND

Primary bilateral macronodular adrenocortical hyperplasia (PBMAH) is a rare form of adrenal Cushing's syndrome. The slowly progressing expansion of bilateral adrenal tissues usually persists for dozens of years, leading to delayed onset with severe conditions due to chronic mild hypercortisolism. About 20-50% cases were found to be caused by inactivating mutation of armadillo repeat-containing protein 5 (ARMC5) gene.

CASE PRESENTATION

A 51-year-old man was admitted for severe diabetes mellitus, resistant hypertension, centripedal obesity and edema. PBMAH was diagnosed after determination of adrenocorticotropic hormone and cortisol levels, dexamethasone suppression tests and abdominal contrast-enhanced CT scanning. The metabolic disorders of the patient remarkably improved after sequentially bilateral laparoscopic adrenalectomy combined with hormone replacement. Sanger sequencing showed germline nonsense mutation of ARMC5 c.967C>T (p.Gln323Ter). The second somatic missense mutation of ARMC5 was detected in one out of two resected nodules, reflecting the second-hit model of tumorigenesis. Routine genetic testing in his apparently healthy offspring showed one of two daughters and one son harbored the germline mutation.

CONCLUSIONS

In conclusion, our case report highlight the importance of genetic testing in the molecular diagnosis of PBMAH. Genetic screening in related family members will find out asymptomatic variant carriers to guide life-long follow-up.

Open versus minimally invasive surgery for suspected adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare malignancy with a poor prognosis. Although laparoscopy has been widely adopted for management of benign adrenal tumors, minimally invasive surgery for ACC remains controversial. Retrospective analyses, frequently with fewer than one hundred participants, comprise the majority of the literature. High-quality data regarding the optimal surgical approach for ACC are lacking due to the rarity of the disease and the fact that determination of tumor type (e.g., adenoma or carcinoma) is determined after adrenalectomy, since adrenal tumors are generally not biopsied. While the benefits of minimally invasive surgery including lower intra-operative blood loss and decreased hospital length-of-stay have been consistently demonstrated, clinical equipoise for long-term survival and recurrence outcomes between open and minimally invasive adrenalectomy (MIA) remains. This review examines retrospective studies that directly compare patients with ACC who underwent either open or laparoscopic adrenalectomy, and considers these findings in the context of current guideline recommendations for surgical management of ACC.

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.

What Did We Learn from the Molecular Biology of Adrenal Cortical Neoplasia? From Histopathology to Translational Genomics

Approximately one-tenth of the general population exhibit adrenal cortical nodules, and the incidence has increased. Afflicted patients display a multifaceted symptomatology-sometimes with rather spectacular features. Given the general infrequency as well as the specific clinical, histological, and molecular considerations characterizing these lesions, adrenal cortical tumors should be investigated by endocrine pathologists in high-volume tertiary centers. Even so, to distinguish specific forms of benign adrenal cortical lesions as well as to pinpoint malignant cases with the highest risk of poor outcome is often challenging using conventional histology alone, and molecular genetics and translational biomarkers are therefore gaining increased attention as a possible discriminator in this context. In general, our understanding of adrenal cortical tumorigenesis has increased tremendously the last decade, not least due to the development of next-generation sequencing techniques. Comprehensive analyses have helped establish the link between benign aldosterone-producing adrenal cortical proliferations and ion channel mutations, as well as mutations in the protein kinase A (PKA) signaling pathway coupled to cortisol-producing adrenal cortical lesions. Moreover, molecular classifications of adrenal cortical tumors have facilitated the distinction of benign from malignant forms, as well as the prognostication of the individual patients with verified adrenal cortical carcinoma, enabling high-resolution diagnostics that is not entirely possible by histology alone. Therefore, combinations of histology, immunohistochemistry, and next-generation multi-omic analyses are all needed in an integrated fashion to properly distinguish malignancy in some cases. Despite significant progress made in the field, current clinical and pathological challenges include the preoperative distinction of non-metastatic low-grade adrenal cortical carcinoma confined to the adrenal gland, adoption of individualized therapeutic algorithms aligned with molecular and histopathologic risk stratification tools, and histological confirmation of functional adrenal cortical disease in the context of multifocal adrenal cortical proliferations. We herein review the histological, genetic, and epigenetic landscapes of benign and malignant adrenal cortical neoplasia from a modern surgical endocrine pathology perspective and highlight key mechanisms of value for diagnostic and prognostic purposes.

β-catenin in adrenal zonation and disease

The Wnt signaling pathway is a critical mediator of the development and maintenance of several tissues. The adrenal cortex is highly dependent upon Wnt/β-catenin signaling for proper zonation and endocrine function. Adrenocortical cells emerge in the peripheral capsule and subcapsular cortex of the gland as progenitor cells that centripetally differentiate into steroid hormone-producing cells of three functionally distinct concentric zones that respond robustly to various endocrine stimuli. Wnt/β-catenin signaling mediates adrenocortical progenitor cell fate and tissue renewal to maintain the gland throughout life. Aberrant Wnt/β-catenin signaling contributes to various adrenal disorders of steroid production and growth that range from hypofunction and hypoplasia to hyperfunction, hyperplasia, benign adrenocortical adenomas, and malignant adrenocortical carcinomas. Great strides have been made in defining the molecular underpinnings of adrenocortical homeostasis and disease, including the interplay between the capsule and cortex, critical components involved in maintaining the adrenocortical Wnt/β-catenin signaling gradient, and new targets in adrenal cancer. This review seeks to examine these and other recent advancements in understanding adrenocortical Wnt/β-catenin signaling and how this knowledge can inform therapeutic options for adrenal disease.

Molecular Genetic and Genomic Alterations in Cushing's Syndrome and Primary Aldosteronism

The genetic alterations that cause the development of glucocorticoid and/or mineralocorticoid producing benign adrenocortical tumors and hyperplasias have largely been elucidated over the past two decades through advances in genomics. In benign aldosterone-producing adrenocortical tumors and hyperplasias, alteration of intracellular calcium signaling has been found to be significant in aldosterone hypersecretion, with causative defects including those in KCNJ5, ATP1A1, ATP2B3, CACNA1D, CACNA1H, and CLCN2. In benign cortisol-producing adrenocortical tumors and hyperplasias abnormal cyclic adenosine monophosphate-protein kinase A signaling has been found to play a central role in tumorigenesis, with pathogenic variants in GNAS, PRKAR1A, PRKACA, PRKACB, PDE11A, and PDE8B being implicated. The role of this signaling pathway in the development of Cushing's syndrome and adrenocortical tumors was initially discovered through the study of the underlying genetic defects causing the rare multiple endocrine neoplasia syndromes McCune-Albright syndrome and Carney complex with subsequent identification of defects in genes affecting the cyclic adenosine monophosphate-protein kinase A pathway in sporadic tumors. Additionally, germline pathogenic variants in ARMC5, a putative tumor suppressor, were found to be a cause of cortisol-producing primary bilateral macronodular adrenal hyperplasia. This review describes the genetic causes of benign cortisol- and aldosterone-producing adrenocortical tumors.

[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.

Update of Genetic and Molecular Causes of Adrenocortical Hyperplasias Causing Cushing Syndrome

Bilateral hyperplasias of the adrenal cortex are rare causes of chronic endogenous hypercortisolemia also called Cushing syndrome. These hyperplasias have been classified in two categories based on the adrenal nodule size: the micronodular types include Primary Pigmented Nodular Adrenocortical Disease (PPNAD) and isolated Micronodular Adrenal Disease (iMAD) and the macronodular also named Primary Bilateral Macronodular Adrenal Hyperplasia (PBMAH). This review discusses the genetic and molecular causes of these different forms of hyperplasia that involve mutations and dysregulation of various regulators of the cAMP/protein kinase A (PKA) pathway. PKA signaling is the main pathway controlling cortisol secretion in adrenocortical cells under ACTH stimulation. Although mutations of the regulatory subunit R1α of PKA (PRKAR1A) is the main cause of familial and sporadic PPNAD, inactivation of two cAMP-binding phosphodiesterases (PDE11A and PDE8B) are associated with iMAD even if they are also found in PPNAD and PBMAH cases. Interestingly, PBMAH that is observed in multiple familial syndrome such as APC, menin, fumarate hydratase genes, has initially been associated with the aberrant expression of G-protein coupled receptors (GPCR) leading to an activation of cAMP/PKA pathway. However, more recently, the discovery of germline mutations in Armadillo repeat containing protein 5 (ARMC5) gene in 25-50% of PBMAH patients highlights its importance in the development of PBMAH. The potential relationship between ARMC5 mutations and aberrant GPCR expression is discussed as well as the potential other causes of PBMAH.

Adrenocortical tumorigenesis: Lessons from genetics

Advances in genomics over the past two decades have allowed for elucidation of the genetic alterations leading to the development of adrenocortical tumors and/or hyperplasias. These molecular changes were initially discovered through the study of rare familial tumor syndromes such as McCune-Albright Syndrome, Carney complex, Li-Fraumeni syndrome, and Beckwith-Wiedemann syndrome, with the identification of alterations in genes and molecular pathways that subsequently led to the discovery of aberrations in these or related genes and pathways in sporadic tumors. Genetic alterations in GNAS, PRKAR1A, PRKACA, PRKACB, PDE11A, and PDE8B, that lead to aberrant cyclic adenosine monophosphate-protein (cAMP) kinase A signaling, were found to play a major role in the development of benign cortisol-producing adrenocortical tumors and/or hyperplasias, whereas genetic defects in KCNJ5, ATP1A1, ATP2B3, CACNA1D, CACNA1H, and CLCN2 were implicated in the development of benign aldosterone-producing tumors and/or hyperplasias through modification of intracellular calcium signaling. Germline ARMC5 defects were found to cause the development of primary bilateral macronodular adrenocortical hyperplasia with glucocorticoid and/or mineralocorticoid oversecretion. Adrenocortical carcinoma was linked primarily to aberrant p53 signaling and/or Wnt-β-catenin signaling, as well as IGF2 overexpression, with frequent genetic alterations in TP53, ZNRF3, CTNNB1, and 11p15. This review focuses on the genetic underpinnings of benign cortisol- and aldosterone-producing adrenocortical tumors/hyperplasias and adrenocortical carcinoma.

Adrenal cortical carcinoma: pathology, genomics, prognosis, imaging features, and mimics with impact on management

Adrenocortical carcinoma (ACC) is a rare tumor with a poor prognosis. Most tumors are either metastatic or locally invasive at the time of diagnosis. Differentiation between ACC and other adrenal masses depends on clinical, biochemical, and imaging factors. This review will discuss the genetics, pathological, and imaging feature of ACC.

Small adrenal incidentaloma becoming an aggressive adrenocortical carcinoma in a patient carrying a germline APC variant

PURPOSE

Recent guidelines on adrenal incidentalomas suggested in patients with an indeterminate adrenal mass and no significant hormone excess that follow up with a repeat noncontrast CT or MRI after 6-12 months may be an option.

METHODS

We report the case of a 32-year-old woman who presented with a 2.9 × 1.9 cm left adrenal incidentaloma that was stable in size for 4 years. Ten years later the left adrenal mass was a stage IV adrenocortical carcinoma (ACC).

RESULTS

In 2006, a 32-year-old French Canadian woman was referred to endocrinology for a left 2.9 × 1.9 cm incidentally discovered adrenal mass (31 HU). She had normal hormonal investigation. The patient was followed with adrenal imaging and hormonal investigation yearly for 4 years and the lesion stayed stable in size over the 4 years. Ten years later, in 2016, the patient presented with renal colic. Urological CT unexpectedly revealed that the left adrenal mass was now measuring 9 × 8.2 cm and 2 new hepatic lesions were found. Biochemical workup demonstrated hypercorticism and hyperandrogenemia: plasma cortisol after 1 mg overnight DST of 476 nmol/L and DHEA-S of 14.0 μmol/L (N 0.9-6.5). Twenty-four hour urine steroid profiling was consistent with an adrenocortical carcinoma (ACC) co-secreting cortisol, androgens and glucocorticoid precursors. The diagnosis of ACC with hepatic ACC metastases was confirmed at histology. Following genetic analysis, germline heterozygous variant of uncertain significance (VUS) was identified in the exon 16 of the APC gene (c.2414G > A, p.Arg805Gln). Immunohistochemical staining's of the ACC was positive for IGF-2 and cytoplasmic/nuclear β-catenin staining.

CONCLUSIONS

This case illustrates that (1) small adrenal incidentaloma stable in size may evolve to ACC and (2) better genetic characterization of these patients may eventually give clues on this unusual evolution.

Cushing syndrome: Old and new genes

Cushing syndrome (CS) describes the signs and symptoms caused by exogenous or endogenous hypercortisolemia. Endogenous CS is caused by either ACTH-dependent sources (pituitary or ectopic) or ACTH-independent (adrenal) hypercortisolemia. Several genes are currently known to contribute to the pathogenesis of CS. Germline gene defects, such as MEN1, AIP, PRKAR1A and others, often present in patients with pituitary or adrenal involvement as part of a genetic syndrome. Somatic defects in genes, such as USP8, TP53, and others, are also involved in the development of pituitary or adrenal tumors in a large percentage of patients with CS, and give insight in pathways involved in pituitary or adrenal tumorigenesis.

A Diagnostic Approach to Adrenocortical Tumors

Adrenocortical tumors range from primary bilateral micronodular or macronodular forms of adrenocortical disease to conventional adrenocortical adenomas and carcinomas. Accurate classification of these neoplasms is critical given the varied pathogenesis, clinical behavior, and outcome of these different lesions. Confirmation of adrenocortical origin, diagnosing malignancy, providing relevant prognostic information in adrenocortical carcinoma, and correlation of laboratory results with clinicopathologic findings are among the important responsibilities of pathologists who evaluate these lesions. This article focuses on a practical approach to the evaluation of adrenocortical tumors with an emphasis on clinical and imaging findings, morphologic characteristics, and multifactorial diagnostic schemes and algorithms.

Diseases Predisposing to Adrenocortical Malignancy (Li-Fraumeni Syndrome, Beckwith-Wiedemann Syndrome, and Carney Complex)

Adrenocortical malignancies can occur in the context of several tumor predisposition syndromes.The Carney complex (CNC) is responsible for the majority of primary pigmented nodular adrenal diseases and is more rarely associated with adrenocortical carcinoma (ACC). Other core manifestations of CNC include cardiac and cutaneous myxomas, lentiginosis, somatotroph pituitary adenomas, Sertoli tumors, melanocytic schwannoma, and thyroid, breast, and bone tumors. CNC is mostly due to germline inactivating mutations of PRKAR1A.The majority of childhood ACC are related to genetic predisposition. The Beckwith-Wiedemann syndrome (BWS) is an overgrowth and tumor predisposition syndrome due to genetic or epigenetic alterations at the 11p15 locus. Classical tumor spectrum of BWS includes embryonal tumors and childhood ACC. The Li-Fraumeni syndrome (LFS) is a devastating tumor predisposition syndrome, due to germline inactivating mutations of TP53, and characterized by a high, various, and early-onset cancer risk. LFS spectrum includes premenopausal breast cancer, soft-tissue sarcoma, osteosarcoma, central nervous system tumor, and ACC, accounting for 50-80% of pediatric cases. Finally, germline predisposition affects up to 10% of adult ACC patients, mostly in part of LFS and Lynch syndrome.This chapter focuses on the diagnosis, screening, and management of adrenal tumors in part of these tumor predisposition syndromes.

Adrenocortical Carcinoma in Children: A Clinicopathological Analysis of 41 Patients at the Mayo Clinic from 1950 to 2017

BACKGROUND/AIMS

Adrenocortical carcinoma (ACC) is an aggressive childhood cancer. Limited evidence exists on a definite histopathological criterion to differentiate ACC from adrenocortical adenoma. The aim of this study was to investigate the clinicopathological data of children with ACC, identify prognostic factors, and validate a histopathological criterion to differentiate ACC from adrenocortical adenoma.

METHODS

This retrospective cohort included 41 children, followed at the Mayo Clinic from 1950 to 2017 (onset of symptoms ≤21 years). Outcomes of interest were: alive with no evidence of disease, alive with evidence of disease, and dead of disease.

RESULTS

Median age at onset of symptoms was 15.7 years (n = 41; range, 0.2-21 years). Female:male ratio was 3.6: 1. Mixed symptomatology (> 1 hormone abnormality) was the most common presentation (54%, n = 22). Sixty-six percent of patients (n = 27 out of 41) underwent total adrenalectomy. Metastatic disease was more common in children aged > 12 years (p = 0.002 compared to < 4 years). The most common sites of metastases were the liver and lungs. Overall 2-year and 5-year survival rates were 61% (95% CI 45-77) and 46% (95% CI 30-62), respectively. Metastasis at the time of diagnosis was independently associated with poor prognosis (risk ratio 13.7%; 95% CI 3.9-87.7). Weiss criteria (29%) and modified Weiss criteria (33%) were less accurate in younger patients (< 12 years), compared to the Wieneke index (100%).

CONCLUSION

The presence of metastases was an independent prognostic factor. The Wieneke index was the most accurate in predicting clinical outcomes in younger children.

An update on adrenal endocrinology: significant discoveries in the last 10 years and where the field is heading in the next decade

The last 10 years have produced an amazing number of significant discoveries in the field of adrenal endocrinology. The development of the adrenal gland was linked to specific molecules. Cortisol-producing lesions were associated mostly with defects of the cyclic AMP (cAMP) signaling pathway, whereas aldosterone-producing lesions were found to be the result of defects in aldosterone biosynthesis or the potassium channel KCNJ5 and related molecules. Macronodular adrenal hyperplasia was linked to ARMC5 defects and new genes were found to be involved in adrenocortical cancer (ACC). The succinate dehydrogenase (SDH) enzyme was proven to be the most important molecular pathway involved in pheochromocytomas, along with several other genes. Adrenomedullary tumors are now largely molecularly elucidated. Unfortunately, most of these important discoveries have yet to produce new therapeutic tools for our patients with adrenal diseases: ACC in its advanced stages remains largely an untreatable disorder and malignant pheochromocytomas are equally hard to treat. Thus, the challenge for the next 10 years is to translate the important discoveries of the previous decade into substantial advances in the treatment of adrenal disorders and tumors.

Therapeutic Targets for Adrenocortical Carcinoma in the Genomics Era

Adrenocortical carcinoma (ACC) is a rare and often fatal cancer, affecting ~1 person per million per year worldwide. Approximately 75% of patients with ACC eventually develop metastases and progress on the few available standard-of-care medical therapies, highlighting an incredible need for an improved understanding of the molecular biology of this disease. Although it has long been known that ACC is characterized by certain histological and genetic features (e.g., high mitotic activity, chromosomal instability, and overexpression of IGF2), only in the last two decades of genomics has the molecular landscape of ACC been more thoroughly characterized. In this review, we describe the findings of historical genetics and recent genomics studies on ACC and discuss how underlying concepts emerging from these studies contribute to the current model of critical pathways for adrenocortical carcinogenesis. Integrative synthesis across these studies reveals that ACC consists of three distinct molecular subtypes with divergent clinical outcomes and implicates differential regulation of Wnt signaling, cell cycle, DNA methylation, immune biology, and steroidogenesis in ACC biology. These cellular programs are pharmacologically targetable and may enable the development of therapeutic strategies to improve outcomes for patients facing this devastating disease.

65 YEARS OF THE DOUBLE HELIX: Endocrine tumour syndromes in children and adolescents

As medicine is poised to be transformed by incorporating genetic data in its daily practice, it is essential that clinicians familiarise themselves with the information that is now available from more than 50 years of genetic discoveries that continue unabated and increase by the day. Endocrinology has always stood at the forefront of what is called today 'precision medicine': genetic disorders of the pituitary and the adrenal glands were among the first to be molecularly elucidated in the 1980s. The discovery of two endocrine-related genes, GNAS and RET, both identified in the late 1980s, contributed greatly in the understanding of cancer and its progression. The use of RET mutation testing for the management of medullary thyroid cancer was among the first and one of most successful applications of genetics in informing clinical decisions in an individualised manner, in this case by preventing cancer or guiding the choice of tyrosine kinase inhibitors in cancer treatment. New information emerges every day in the genetics or system biology of endocrine disorders. This review goes over most of these discoveries and the known endocrine tumour syndromes. We cover key genetic developments for each disease and provide information that can be used by the clinician in daily practice.

Genetics of primary macronodular adrenal hyperplasia

Recent advances in molecular genetics investigations of primary macronodular adrenal hyperplasia (PMAH) have been providing new insights for the research on this issue. The cAMP-dependent pathway is physiologically triggered by ACTH and its receptor, MC2-R, in adrenocortical cells. Different mechanisms of this cascade may be altered in some functioning adrenal cortical disorders. Activating somatic mutations of the GNAS gene (known as gsp oncogene) which encodes the stimulatory G protein alpha-subunit (Gsα) have been found in a small number of adrenocortical secreting adenomas and rarely in PMAH. Lately, ARMC5 was linked to the cyclic AMP signaling pathway, which could be implicated in all of mechanisms of cortisol-secreting by macronodules adrenal hyperplasia and the molecular defects in: G protein aberrant receptors; MC2R; GNAS; PRKAR1A; PDE11A; PDE8B. Around 50 % of patient's relatives with PMAH and 30 % of apparently sporadic hypercortisolism carried ARMC5 mutations. Therefore, PMAH is genetically determined more frequently than previously believed. This review summarizes the most important molecular mechanisms involved in PMAH.

Characteristics of Adrenal Masses in Familial Adenomatous Polyposis

BACKGROUND

Adrenal masses are a known extraintestinal manifestation of familial adenomatous polyposis. However, the literature on this association is largely confined to case reports.

OBJECTIVE

This study aimed to determine the characteristics of adrenal masses in familial adenomatous polyposis and their clinical significance, as well as to estimate their prevalence. Mutational analysis was conducted to determine if any potential genotype-phenotype correlations exist.

DESIGN

This is a retrospective cohort study.

SETTING

Analysis included all patients meeting the criteria of classic familial adenomatous polyposis who were registered with the Familial Gastrointestinal Cancer Registry, a national Canadian database.

PATIENTS

Appropriate imaging or autopsy reports were available in 311 registry patients. Patients with adrenal metastases were excluded.

OUTCOME MEASURES

Data collection included demographic data, mutation genotype, adrenal mass characteristics, surgical interventions and mortality.

RESULTS

The prevalence of adrenal masses was 16% (n = 48/311). The median age at diagnosis of adrenal mass was 45 years. The median diameter of adrenal mass at diagnosis was 1.7 cm (interquartile range, 1.4-3.0) with a median maximal diameter of 2.5 cm (interquartile range, 1.7-4.1) with median imaging follow-up of 48 months. The majority of adrenal masses were benign (97%, n = 61/63). Surgery was performed on 7 patients because of concerns for size, malignancy, or hormonal secretion. One adrenal-related death was due to an adrenocortical carcinoma. Mutation analysis did not identify any specific genotype-phenotype correlations.

LIMITATIONS

There were incomplete or insufficient endocrinology data available in the registry to allow for the analysis of hormone secretion patterns.

CONCLUSIONS

Adrenal masses are approximately twice as prevalent in the familial adenomatous polyposis population as in previous studies of the general population. Nearly all mutations led to truncation of the APC gene; however, there was no genetic signature to help predict those at increased risk. The majority of adrenal lesions identified were of benign etiology; thus, an intensive management or surveillance strategy with imaging screening is likely unwarranted. See Video Abstract at http://links.lww.com/DCR/A507.

Genetics of Cushing's Syndrome

The knowledge on the molecular and genetic causes of Cushing's syndrome (CS) has greatly increased in the recent years. Somatic mutations leading to overactive 3',5'-cyclic adenosine monophosphate/protein kinase A and wingless-type MMTV integration site family/beta-catenin pathways are the main molecular mechanisms underlying adrenocortical tumorigenesis. Corticotropinomas are characterized by resistance to glucocorticoid negative feedback, impaired cell cycle control and overexpression of pathways sustaining ACTH secretion. Recognizing the genetic defects behind corticotroph and adrenocortical tumorigenesis proves crucial for tailoring the clinical management of CS patients and for designing strategies for genetic counseling and clinical screening to be applied in routine medical practice.

The Many Faces of Primary Aldosteronism and Cushing Syndrome: A Reflection of Adrenocortical Tumor Heterogeneity

Adrenal cortical tumors constitute a heterogeneous group of neoplasms with distinct clinical, morphological, and molecular features. Recent discoveries of specific genotype–phenotype correlations in adrenal cortical adenomas have transformed our understanding of their respective endocrine syndromes. Indeed, a proportion of patients with primary aldosteronism are now known to harbor adrenal cortical adenomas with heterogeneous molecular alterations (KCNJ5, ATP1A1, ATP2B3, and CACNA1D) involving the calcium/calmodulin kinase signaling pathway. Several lines of evidence suggest that KCNJ5-mutant aldosterone-producing adenomas have distinct clinicopathological phenotype compared to those harboring ATP1A1, ATP2B3, and CACNA1D mutations. Benign adrenal cortical tumors presenting with Cushing syndrome often have diverse mutations (PRKACA, PRKAR1A, GNAS, PDE11A, and PDE8B) involving the cyclic AMP signaling pathway. In addition to cortisol-producing adenomas, bilateral micronodular adrenocortical disease and primary bilateral macronodular adrenal hyperplasia (PBMAH) have also expanded the spectrum of benign neoplasms causing adrenal Cushing disease. The recent discovery of inactivating ARMC5 germline mutations in PBMAH has challenged the old belief that this disorder is mainly a sporadic disease. Emerging evidence suggests that PBMAH harbors multiple distinct clonal proliferations, reflecting the heterogeneous genomic landscape of this disease. Although most solitary adrenal cortical tumors are sporadic, there is an increasing recognition that inherited susceptibility syndromes may also play a role in their pathogenesis. This review highlights the molecular and morphological heterogeneity of benign adrenal cortical neoplasms, reflected in the diverse presentations of primary aldosteronism and adrenal Cushing syndrome.

Genetics of tumors of the adrenal cortex

This review describes the molecular alterations observed in the various types of tumors of the adrenal cortex, excluding Conn adenomas, especially the alterations identified by genomic approaches these last five years. Two main forms of bilateral adrenocortical tumors can be distinguished according to size and aspect of the nodules: primary pigmented nodular adrenal disease (PPNAD), which can be sporadic or part of Carney complex and primary bilateral macro nodular adrenal hyperplasia (PBMAH). The bilateral nature of the tumors suggests the existence of an underlying genetic predisposition. PPNAD and Carney complex are mainly due to germline-inactivating mutations of PRKAR1A, coding for a regulatory subunit of PKA, whereas PBMAH genetic seems more complex. However, genome-wide approaches allowed the identification of a new tumor suppressor gene, ARMC5, whose germline alteration could be responsible for at least 25% of PBMAH cases. Unilateral adrenocortical tumors are more frequent, mostly adenomas. The Wnt/beta-catenin pathway can be activated in both benign and malignant tumors by CTNNB1 mutations and by ZNRF3 inactivation in adrenal cancer (ACC). Some other signaling pathways are more specific of the tumor dignity. Thus, somatic mutations of cAMP/PKA pathway genes, mainly PRKACA, coding for the catalytic alpha-subunit of PKA, are found in cortisol-secreting adenomas, whereas IGF-II overexpression and alterations of p53 signaling pathway are observed in ACC. Genome-wide approaches including transcriptome, SNP, methylome and miRome analysis have identified new genetic and epigenetic alterations and the further clustering of ACC in subgroups associated with different prognosis, allowing the development of new prognosis markers.

The Many Faces of Primary Aldosteronism and Cushing Syndrome: A Reflection of Adrenocortical Tumor Heterogeneity

Adrenal cortical tumors constitute a heterogeneous group of neoplasms with distinct clinical, morphological, and molecular features. Recent discoveries of specific genotype-phenotype correlations in adrenal cortical adenomas have transformed our understanding of their respective endocrine syndromes. Indeed, a proportion of patients with primary aldosteronism are now known to harbor adrenal cortical adenomas with heterogeneous molecular alterations (KCNJ5, ATP1A1, ATP2B3, and CACNA1D) involving the calcium/calmodulin kinase signaling pathway. Several lines of evidence suggest that KCNJ5-mutant aldosterone-producing adenomas have distinct clinicopathological phenotype compared to those harboring ATP1A1, ATP2B3, and CACNA1D mutations. Benign adrenal cortical tumors presenting with Cushing syndrome often have diverse mutations (PRKACA, PRKAR1A, GNAS, PDE11A, and PDE8B) involving the cyclic AMP signaling pathway. In addition to cortisol-producing adenomas, bilateral micronodular adrenocortical disease and primary bilateral macronodular adrenal hyperplasia (PBMAH) have also expanded the spectrum of benign neoplasms causing adrenal Cushing disease. The recent discovery of inactivating ARMC5 germline mutations in PBMAH has challenged the old belief that this disorder is mainly a sporadic disease. Emerging evidence suggests that PBMAH harbors multiple distinct clonal proliferations, reflecting the heterogeneous genomic landscape of this disease. Although most solitary adrenal cortical tumors are sporadic, there is an increasing recognition that inherited susceptibility syndromes may also play a role in their pathogenesis. This review highlights the molecular and morphological heterogeneity of benign adrenal cortical neoplasms, reflected in the diverse presentations of primary aldosteronism and adrenal Cushing syndrome.

Genetic Causes of Functional Adrenocortical Adenomas

Aldosterone and cortisol, the main mineralocorticoid and glucocorticoid hormones in humans, are produced in the adrenal cortex, which is composed of three concentric zones with specific functional characteristics. Adrenocortical adenomas (ACAs) can lead to the autonomous secretion of aldosterone responsible for primary aldosteronism, the most frequent form of secondary arterial hypertension. In the case of cortisol production, ACAs lead to overt or subclinical Cushing syndrome. Genetic analysis driven by next-generation sequencing technology has enabled the discovery, during the past 7 years, of the genetic causes of a large subset of ACAs. In particular, somatic mutations in genes regulating intracellular ionic homeostasis and membrane potential have been identified in aldosterone-producing adenomas. These mutations all promote increased intracellular calcium concentrations, with activation of calcium signaling, the main trigger for aldosterone production. In cortisol-producing adenomas, recurrent somatic mutations in PRKACA (coding for the cyclic adenosine monophosphate-dependent protein kinase catalytic subunit α) affect cyclic adenosine monophosphate-dependent protein kinase A signaling, leading to activation of cortisol biosynthesis. In addition to these specific pathways, the Wnt/β-catenin pathway appears to play an important role in adrenal tumorigenesis, because β-catenin mutations have been identified in both aldosterone- and cortisol-producing adenomas. This, together with different intermediate states of aldosterone and cortisol cosecretion, raises the possibility that the two conditions share a certain degree of genetic susceptibility. Alternatively, different hits might be responsible for the diseases, with one hit leading to adrenocortical cell proliferation and nodule formation and the second specifying the hormonal secretory pattern.

Adrenal Lesions in Patients With (Attenuated) Familial Adenomatous Polyposis and MUTYH-Associated Polyposis

BACKGROUND

The reported proportion of patients with familial adenomatous polyposis who have adrenal lesions varies between 7% and 13% compared with 4% in the general population; the prevalence of adrenal lesions in patients with attenuated familial adenomatous polyposis and MUTYH-associated polyposis is unknown. Data on the clinical relevance and clinical course are limited.

OBJECTIVE

We aimed to report on the frequency, characteristics, and progression of adrenal lesions in polyposis patients.

DESIGN

This was a historical cohort study.

SETTINGS

The study was performed at the Academic Medical Center, Amsterdam.

PATIENTS

All of the patients with familial adenomatous polyposis, attenuated familial adenomatous polyposis, and MUTYH-associated polyposis were included. Medical charts and imaging reports were analyzed for data on adrenal lesions. A radiologist reassessed all of the images. Patients had not routinely been screened for adrenal lesions.

MAIN OUTCOME MEASURES

The frequency, characteristics, and progression of adrenal lesions in patients with polyposis who underwent abdominal imaging were assessed. Findings were compared with a reference.

RESULTS

A total of 39 adrenal lesions were identified in 23 (26%) of 90 patients with familial adenomatous polyposis, 2 (18%) of 11 with attenuated familial adenomatous polyposis, and 5 (24%) of 21 with MUTYH-associated polyposis. Mean age at time of detection was 50.7 years (range, 17.1-83.3 y). Median lesion size at baseline was 1.4 cm (range, 1.0-5.0 cm) versus 1.7 cm (range, 1.0-5.7 cm) after a median of 3.5 years (range, 1.0-11.4 y). Two patients were diagnosed with a hyperfunctioning lesion, and 4 underwent adrenalectomy: 3 lesions appeared benign, and 1 was oncocytic of uncertain malignant potential. The OR for detecting at least 1 lesion in a patient with polyposis versus reference was 6.2 (95% CI, 3.2-12.3), with no significant differences in ORs among the 3 syndromes.

LIMITATIONS

The study was limited by its retrospective design.

CONCLUSIONS

Adrenal lesions are frequent in patients with polyposis who undergo abdominal imaging. They appear to follow a benign and slowly progressive course and are mostly nonhyperfunctioning. See Abstract Video at http://links.lww.com/DCR/A323.

Genetics of Adrenocortical Development and Tumors

This article links the understanding of developmental physiology of the adrenal cortex to adrenocortical tumor formation. Many molecular mechanisms that lead to formation of adrenocortical tumors have been discovered via next-generation sequencing approaches. The most frequently mutated genes in adrenocortical tumors are also factors in normal adrenal development and homeostasis, including those that alter the p53 and Wnt/β-catenin pathways. In addition, dysregulated protein kinase A signaling and ARMC5 mutations have been identified as key mediators of adrenocortical tumorigenesis. The growing understanding of genetic changes that orchestrate adrenocortical development and disease pave the way for potential targeted treatment strategies.

A novel FOXO1-mediated dedifferentiation blocking role for DKK3 in adrenocortical carcinogenesis

Background

Dysregulated WNT signaling dominates adrenocortical malignancies. This study investigates whether silencing of the WNT negative regulator DKK3 (Dickkopf-related protein 3), an implicated adrenocortical differentiation marker and an established tumor suppressor in multiple cancers, allows dedifferentiation of the adrenal cortex.

Methods

We analyzed the expression and regulation of DKK3 in human adrenocortical carcinoma (ACC) by qRT-PCR, immunofluorescence, promoter methylation assay, and copy number analysis. We also conducted functional studies on ACC cell lines, NCI-H295R and SW-13, using siRNAs and enforced DKK3 expression to test DKK3’s role in blocking dedifferentiation of adrenal cortex.

Results

While robust expression was observed in normal adrenal cortex, DKK3 was down-regulated in the majority (>75%) of adrenocortical carcinomas (ACC) tested. Both genetic (gene copy loss) and epigenetic (promoter methylation) events were found to play significant roles in DKK3 down-regulation in ACCs. While NCI-H295R cells harboring β-catenin activating mutations failed to respond to DKK3 silencing, SW-13 cells showed increased motility and reduced clonal growth. Conversely, exogenously added DKK3 also increased motility of SW-13 cells without influencing their growth. Enforced over-expression of DKK3 in SW-13 cells resulted in slower cell growth by an extension of G1 phase, promoted survival of microcolonies, and resulted in significant impairment of migratory and invasive behaviors, largely attributable to modified cell adhesions and adhesion kinetics. DKK3-over-expressing cells also showed increased expression of Forkhead Box Protein O1 (FOXO1) transcription factor, RNAi silencing of which partially restored the migratory proficiency of cells without interfering with their viability.

Conclusions

DKK3 suppression observed in ACCs and the effects of manipulation of DKK3 expression in ACC cell lines suggest a FOXO1-mediated differentiation-promoting role for DKK3 in the adrenal cortex, silencing of which may allow adrenocortical dedifferentiation and malignancy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3152-5) contains supplementary material, which is available to authorized users.

Adrenocortical neoplasms in adulthood and childhood: distinct presentation. Review of the clinical, pathological and imaging characteristics

Adrenocortical tumors (ACT) in adulthood and childhood vary in clinical, histopathological, molecular, prognostic, and imaging aspects. ACT are relatively common in adults, as adenomas are often found incidentally on imaging. ACT are rare in children, though they have a significantly higher prevalence in the south and southeast regions of Brazil. In clinical manifestation, adults with ACT present more frequently with glucocorticoid overproduction (Cushing syndrome), mineralocorticoid syndromes (Conn syndrome), or the excess of androgens in women. Subclinical tumors are frequently diagnosed late, associated with compression symptoms of abdominal mass. In children, the usual presentation is the virilizing syndrome or virilizing association and hypercortisolism. Histopathological grading and ACT classification in malignant and benign lesions are different for adults and children. In adults, the described criteria are the Hough, Weiss, modified Weiss, and Van Slooten. These scores are not valid for children; there are other criteria, such as proposed by Wieneke and colleagues. In molecular terms, there is also a difference related to genetic alterations found in these two populations. This review discusses the imaging findings of ACT, aiming to characterize the present differences between ACT found in adults and children. We listed several differences between magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography-computed (PET-CT) and also performed a literature review, which focuses on studied age groups of published articles in the last 10 years regarding cortical neoplasm and imaging techniques. Published studies on ACT imaging in children are rare. It is important to stress that the majority of publications related to the differentiation of malignant and benign tumors are based almost exclusively on studies in adults. A minority of articles, however, studied adults and children together, which may not be appropriate.

European Society of Endocrine Surgeons (ESES) and European Network for the Study of Adrenal Tumours (ENSAT) recommendations for the surgical management of adrenocortical carcinoma

BACKGROUND

Radical surgery provides the best chance of cure for adrenocortical carcinoma (ACC), but perioperative surgical care for these patients is yet to be standardized.

METHODS

A working group appointed jointly by ENSAT and ESES used Delphi methodology to produce evidence-based recommendations for the perioperative surgical care of patients with ACC. Papers were retrieved from electronic databases. Evidence and recommendations were classified according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system, and were discussed until consensus was reached within the group.

RESULTS

Twenty-five recommendations for the perioperative surgical care of patients with ACC were formulated. The quality of evidence is low owing to the rarity of the disease and the lack of prospective surgical trials. Multi-institutional prospective cohort studies and prospective RCTs are urgently needed and should be strongly encouraged.

CONCLUSION

The present evidence-based recommendations provide comprehensive advice on the optimal perioperative care for patients undergoing surgery for ACC.

Copy number variation analysis and methylome profiling of a GNAQ-mutant primary meningeal melanocytic tumor and its liver metastasis

Primary meningeal melanocytic tumors have genetic similarities with uveal melanomas, including GNAQ or GNA11 mutations. While BAP1 mutations and loss of chromosome 3 have adverse prognostic meaning in uveal melanoma, genetic alterations associated with metastasis have not been investigated in primary meningeal melanocytic tumors. We describe a 43-year-old female with a GNAQ-mutated, BAP1-wt melanocytic tumor originating in the parietal brain region and liver metastases 4years after initial diagnosis. After repeated surgery and chemotherapy she was treated with the immunomodulatory agent ipilimumab. Tissue from the primary and recurrent intracranial tumor (histologically originally diagnosed as intermediate-grade melanocytoma resp. melanoma) and from the liver metastasis was investigated for genome-wide copy number variations and DNA methylation profile. Complete loss of 10p and 19p, partial loss of 16p and a small deletion on 10q were only present in the liver metastasis and not in the intracranial tumors. The DNA methylation profiles of the intracranial tumors and the liver metastasis resembled those of meningeal melanocytomas. In conclusion, in this report we show that a distant metastasis of a meningeal melanocytic tumor has a similar methylation profile as the primary tumor and suggest that particular copy number variations may be associated with metastatic behavior.

Aldosterone-Producing Adenoma With a Somatic KCNJ5 Mutation Revealing APC-Dependent Familial Adenomatous Polyposis

CONTEXT

Recurrent somatic mutations in KCNJ5, CACNA1D, ATP1A1, and ATP2B3 have been identified in aldosterone-producing adenomas (APAs). The question as to whether they are responsible for both nodulation and aldosterone production is not solved.

CASE DESCRIPTION

We describe the case of a young patient who was diagnosed with severe arterial hypertension due to primary aldosteronism at age 26 years, followed by hemorrhagic stroke 4 years later. Abdominal computed tomography showed bilateral macronodular adrenal hyperplasia. Identification of lateralized aldosterone secretion led to right adrenalectomy, followed by normalization of biochemical and hormonal parameters and amelioration of blood pressure. The resected adrenal showed three nodules, one of them expressing aldosterone synthase and harboring a somatic KNCJ5 mutation. A Weiss revisited index of 3 of the APA prompted us to perform a second 18F-2-fluoro-2-deoxy-D-glucose-positron emission tomography after surgery, which revealed abnormal rectal activity despite the absence of clinical symptoms. Gastrointestinal exploration showed multiple polyps with severe dysplasia, and the diagnosis of familial adenomatous polyposis was established in the presence of a germline heterozygous APC gene mutation. Sequencing of somatic DNA from the APA and a second adrenal nodule revealed biallelic APC inactivation due to loss of heterozygosity in both nodules.

CONCLUSIONS

This case report underlines the need for establishing the frequency of germline APC variants in patients with primary aldosteronism and bilateral macronodular adrenal hyperplasia because their presence may predispose to APA development and severe hypertension well before the first familial adenomatous polyposis symptoms appear. From a mechanistic point of view, it supports a two-hit model for APA development, whereby the first hit drives increased cell proliferation whereas the second hit specifies the pattern of hormonal secretion.

Giant Adrenal Cavernous Hemangioma in a Patient with Familial Adenomatous Polyposis

Adrenal hemangioma is an uncommon benign vascular tumor that is often discovered incidentally. It has never been reported in association with familial adenomatous polyposis. We report a case of a 60-year old man with a history of familial adenomatous polyposis, in whom a huge retroperitoneal cyst of 18x17 cm was discovered during routine radiologic evaluation. Because of the impossibility of ruling out the presence of malignancy, surgical cystectomy was performed, associated to a scheduled total colectomy. Pathological examination revealed that the cyst corresponded to an adrenal cavernous hemangioma. Colonic adenomas did not show signs of degeneration. Screening for adenomatous polyposis coli (APC) gene mutation was not carried out. As familial adenomatous polyposis is known to involve a variety of extracolonic manifestations, this finding raises the suspicion of a possible variant of this syndrome including adrenal hemangioma. An extensive study based on a larger patient series with genetic exploration is necessary.

Immunohistochemical analysis of the Wnt/β-catenin signaling pathway in pancreatic neuroendocrine neoplasms

AIM: To investigate the role of the Wnt/β-catenin pathway in pancreatic neuroendocrine neoplasms (PanNENs).

METHODS: Tissue microarrays containing 88 PanNENs were immunohistochemically labeled with antibodies to β-catenin, E-cadherin, adenomatous polyposis coli (APC), chromogranin and synaptophysin. One case had only metastatic tumors resected, whereas others (n = 87) received pancreatectomy with or without partial hepatectomy. Pathology slides, demographic, clinicopathologic, and follow up data were reviewed. Patients’ demographics, clinicopathologic features, and immunohistochemical results from 87 primary tumors were compared between patients with low stage (stage I/II) and high stage (stage III/IV) tumors. In addition, correlation of immunohistochemical results from primary tumors with disease-specific survival (DSS) was evaluated.

RESULTS: Strong membranous β-catenin staining in the primary tumor was observed in all 13 stage III/IV PanNENs as compared to 47% (35/74) of stage I/II tumors (P < 0.01). However, the strong membranous β-catenin staining was unassociated with tumor grade or DSS. Decreased membranous β-catenin staining was associated with decreased membranous E-cadherin labeling. Nuclear β-catenin staining was seen in 15% (2/13) of stage III/IV PanNENs as compared to 0% (0/74) of stage I/II tumors (P = 0.02). The case with metastasectomy also only showed nuclear β-catenin staining. Two of the three cases with nuclear β-catenin staining were familial adenomatous polyposis (FAP) patients. Lack of APC expression was seen in 70% (57/81) of the cases, including the 3 cases with nuclear β-catenin staining. Expression of E-cadherin and APC in primary tumor was not correlated with tumor grade, tumor stage, or disease specific survival.

CONCLUSION: The Wnt/β-catenin pathway was altered in some PanNENs, but did not Impact DSS. PanNENs in FAP patients demonstrated nuclear β-catenin accumulation and loss of APC.

Investigation of N-cadherin/β-catenin expression in adrenocortical tumors

β-catenin is a multifunctional protein; it is a key component of the Wnt signaling, and it plays a central role in cadherin-based adhesions. Cadherin loss promotes tumorigenesis by releasing membrane-bound β-catenin, hence stimulating Wnt signaling. Cadherins seem to be involved in tumor development, but these findings are limited in adrenocortical tumors (ACTs). The objective of this study was to evaluate alterations in key components of cadherin/catenin adhesion system and of Wnt pathway. This study included eight normal adrenal samples (NA) and 95 ACT: 24 adrenocortical carcinomas (ACCs) and 71 adrenocortical adenomas (ACAs). β-catenin mutations were evaluated by sequencing, and β-catenin and cadherin (E-cadherin and N-cadherin) expression was analyzed by quantitative reverse transcription PCR (qRT-PCR) and by immunohistochemistry (IHC). We identified 18 genetic alterations in β-catenin gene. qRT-PCR showed overexpression of β-catenin in 50 % of ACC (12/24) and in 48 % of ACA (21/44). IHC data were in accordance with qRT-PCR results: 47 % of ACC (7/15) and 33 % of ACA (11/33) showed increased cytoplasmic or nuclear β-catenin accumulation. N-cadherin downregulation has been found in 83 % of ACC (20/24) and in 59 % of ACA (26/44). Similar results were obtained by IHC: N-cadherin downregulation was observed in 100 % (15/15) of ACC and in 55 % (18/33) of ACA. β-catenin overexpression together with the aberrant expression of N-cadherin may play important role in ACT tumorigenesis. The study of differentially expressed genes (such as N-cadherin and β-catenin) may enhance our understanding of the biology of ACT and may contribute to the discovery of new diagnostic and prognostic tools.

ENDOCRINE TUMOURS: The genomics of adrenocortical tumors

The last decade witnessed the emergence of genomics, a set of high-throughput molecular measurements in biological samples. These pan-genomic and agnostic approaches have revolutionized the molecular biology and genetics of malignant and benign tumors. These techniques have been applied successfully to adrenocortical tumors. Exome sequencing identified new major drivers in all tumor types, including KCNJ5, ATP1A1, ATP2B3 and CACNA1D mutations in aldosterone-producing adenomas (APA), PRKACA mutations in cortisol-producing adenomas (CPA), ARMC5 mutations in primary bilateral macronodular adrenocortical hyperplasia (PBMAH) and ZNRF3 mutations in adrenocortical carcinomas (ACC). Moreover, the various genomic approaches - including exome sequencing, transcriptome, miRNome, genome and methylome - converge into a single molecular classification of adrenocortical tumors. Especially for ACC, two main molecular groups have emerged, showing major differences in outcomes. These ACC groups differ by their gene expression profiles, but also by recurrent mutations and specific DNA hypermethylation patterns in the subgroup of poor outcome. The clinical impact of these findings is just starting. The main altered signaling pathways now become therapeutic targets. The molecular groups of diseases individualize robust subtypes within diseases such as APA, CPA, PBMAH and ACC. A revised nosology of adrenocortical tumors should impact the clinical research. Obvious consequences also include genetic counseling for the new genetic diseases such as ARMC5 mutations in PBMAH, and a better prognostication of ACC based on targeted measurements of a few discriminant molecular alterations. Identifying the main molecular groups of adrenocortical tumors by extensively gathering the molecular variations is a significant step forward towards precision medicine.