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

ABCC3 Is a Differential Marker of CYP11B2-Negative Zona Glomerulosa Cells in Human Adrenal Cortex

ATP Binding Cassette Subfamily C Member 3 (ABCC3) is a membrane transporter that exports diverse compounds, influencing drug resistance in cancers and impacting metabolic and malignant diseases. We previously reported ABCC3 upregulation in human adrenal cells under lipid peroxidation-induced oxidative stress. We investigated ABCC3 expression and function in the human adrenal cortex in the context of primary aldosteronism, focusing on its relationship to CYP11B2 (aldosterone synthase) in zona glomerulosa (ZG) cells and aldosterone-producing lesions. ABCC3 expression in aldosterone-producing adenomas (APAs) was markedly reduced compared to the adjacent adrenal cortex, cortisol-producing adenomas, and non-functioning adenomas. The reduction in APAs showed genotypic variability: in APAs harboring KCNJ5 mutations-known drivers of autonomous aldosterone production via altered potassium channel function-ABCC3 mRNA/protein levels were significantly higher than in wild-type KCNJ5 APAs. Spatial transcriptomics and immunofluorescence colocalization revealed an inverse expression pattern between ABCC3 and CYP11B2 (aldosterone synthase) in APAs and aldosterone-producing micronodules (APMs). Notably, high ABCC3 expression was exclusively observed in adrenal ZG cells that lacked CYP11B2 expression. This expression pattern distinguishes ABCC3 from common ZG markers such as KCNJ5 and DAB2, which are expressed across adrenal ZG cells, APMs, and APA tumor cells. In cultured human adrenocortical cells, both angiotensin II stimulation and induced expression of the KCNJ5-L168R mutation resulted in upregulation of CYP11B2 transcription while concomitantly suppressing ABCC3 expression. In conclusion, ABCC3 serves as a novel marker of CYP11B2-negative ZG cells, providing a histopathological tool to differentiate normal adrenal zonation from aldosterone-producing lesions in primary aldosteronism, as well as from cortisol-producing and nonfunctional adenomas.

ccfDNA analysis for the classification of adrenocortical adenomas

BACKGROUND

Somatic alterations are commonly observed in adrenocortical adenomas including cortisol-producing (CPA) [overt Cushing syndrome (CS) or mild autonomous cortisol secretion (MACS)], aldosterone-producing (APA), and non-functioning (NFAT) tumors. We tested whether somatic variants could be detected in circulating cell-free DNA (ccfDNA) from patients with adenomas and potentially contribute to management strategies.

MATERIALS AND METHODS

We investigated 44 patients (17 CPA-MACS, 9 CPA-CS, 12 APA, and 6 NFAT). 23 healthy subjects (HS) served as controls. ccfDNA was extracted from blood samples and quantified with fluorimeter. Tumor DNA (T-DNA) was isolated from paraffin embedded tissue in 17/44 cases. Matched ccfDNA/T-DNA were sequenced using a customized panel including 32 genes. Leucocyte DNA was used to filter out germline variants.

RESULTS

Patients with adenomas had higher total ccfDNA concentrations than HS [median 0.12 (IQR 0.05-0.19) vs. 0.05 (0.00-0.08) ng/µl, P < 0.001], with CPA-CS showing the highest ccfDNA levels [0.18 (0.05-0.47) ng/µl]. Within T-DNA, somatic variants were identified in 53% of adenomas: PRKACA in 2/7 CPA-CS, CTNNB1 in 3/5 CPA-MACS and 1/7 CPA-CS, KCNJ5 in 2/5 APA and CACNA1D in 1/5 APA. Somatic mutations were not detected in any of the investigated ccfDNA samples.

CONCLUSIONS

Total ccfDNA concentrations are higher in patients with CPA-CS. Despite the presence of somatic variants in half of tumor samples, we did not detect any at ccfDNA level. Therefore, this approach appears ineffective for pre-operative detection of genetic alterations.

Adrenal mixed corticomedullary tumors: report of a case with molecular characterization and systematic review

Adrenal mixed corticomedullary tumors (MCMTs) are rare lesions showing a mixture of two cell populations of cortical and medullary lineage. We describe an MCMT case presented in a 56-year-old woman with a history of arterial hypertension and high levels of aldosterone, accompanied by a review of the literature. The adrenalectomy specimen showed a well-circumscribed nodule of 30 mm in size, containing 60% of cells with a cortical phenotype (positive for α-inhibin and melan-A) and 40% of cells with a medullary phenotype (positive for chromogranin-A, GATA-3 and somatostatin receptor 2). There was no significant mitotic activity, necrosis, nor lymphovascular invasion. The GNAS p.(Arg844Cys) mutation, as well as variants of uncertain significance AKAP13 p.(His641Pro) and EPAS1 p.(Ser478del) were detected in the tumor. MCMT is more common in women (75%) with a mean age of 46.6 years (range 16-78). Most patients present with hypertension (79%), frequently associated with Cushing's syndrome, (39%), diabetes (21%), aldosteronism (15%), and/or hyperandrogenism (6%). Laboratory data showed elevated levels of both cortisol and cathecholamines and/or their metabolites in more than 50% of cases, supporting the dual nature of the tumor. Most MCMTs are benign, but aggressive behavior was detected in four (12%) cases, all of them showing large size (80-220 mm), poor delimitation, venous invasion, necrosis, and/or high proliferation rates. The pathogenesis is unknown, but our findings suggest a tumor histogenesis from the cortical cellular component through the regulation of the protein kinase A pathway and secondary proliferation of the medullary component.

Cushing syndrome

Cushing syndrome (CS) is a constellation of signs and symptoms caused by excessive exposure to exogenous or endogenous glucocorticoid hormones. Endogenous CS is caused by increased cortisol production by one or both adrenal glands (adrenal CS) or by elevated adrenocorticotropic hormone (ACTH) secretion from a pituitary tumour (Cushing disease (CD)) or non-pituitary tumour (ectopic ACTH secretion), which stimulates excessive cortisol production. CS is associated with severe multisystem morbidity, including impaired cardiovascular and metabolic function, infections and neuropsychiatric disorders, which notably reduce quality of life. Mortality is increased owing to pulmonary emboli, infection, myocardial infarction and cerebrovascular accidents. The clinical presentation is variable and because some CS signs and symptoms are common in the general population, the diagnosis might not be considered until many features have accumulated. Guidelines recommend screening patients with suspected CS with 24-h urine cortisol, bedtime salivary cortisol and/or 1 mg dexamethasone suppression test. Subsequently, determining the aetiology of CS is important as it affects management. The first-line therapy for all aetiologies of endogenous CS is surgical resection of the causal tissue, including corticotroph adenoma or ectopic tumour for ACTH-dependent CS or unilateral or bilateral adrenalectomy for adrenal CS. Second-line therapies include steroidogenesis inhibitors for any cause of CS, pituitary radiation (with or without steroidogenesis inhibitors) for CD, and bilateral adrenalectomy for ACTH-dependent causes of CS.

Staining patterns of aldosterone synthase in patients undergoing surgery for primary aldosteronism: Proposal for system of categorization and investigation of clinical and biochemical correlation

BACKGROUND

How aldosterone synthase (CYP11B2) staining patterns impact patient outcomes in those with unilateral primary aldosteronism is not well described. We hypothesized that a system of categorization would benefit future research and that clinical and biochemical outcomes after unilateral adrenalectomy are impacted by different CYP11B2 staining patterns.

METHODS

A retrospective review of patients undergoing adrenalectomy for primary aldosteronism from January 2015 to September 2023 was conducted. Demographics, clinical, and pathologic data were analyzed. A system of categorization of staining patterns was developed. Clinical and biochemical outcomes were compared with staining patterns to assess differences and determine correlation. Descriptive and statistical analyses were performed using SPSS.

RESULTS

Forty-three patients were included. The following CYP11B2 staining patterns were identified: (1) single adenoma; (2) aldosterone producing nodule(s) or micronodule(s); (3) combination of type 1 and type 2; (4) hyperplasia; and (5) aldosterone-producing adrenocortical cancer. In total, 23 of 43 revealed CYP11B2 staining in a single adenoma only. Staining in 3/23 involved a portion of the adenoma. 4/9 patients age <40 had areas of CYP11B2 staining in nonadenomatous tissue. Complete biochemical cure was noted in 37 of 43 (86%) and complete clinical cure in 23.2%. There were no differences between staining pattern and sex, race, or age. CYP11B2 staining pattern did not correlate with early clinical or biochemical outcomes.

CONCLUSION

Adrenalectomy specimens from patients treated for primary aldosteronism reveal multiple CYP11B2 staining patterns, including in nonadenomatous tissue in many patients. The impact of these patterns on clinical outcomes requires additional investigation. Uniform categorization of staining patterns will allow for consistent reporting across studies.

The road ahead: a brief guide to navigating the 2022 WHO classification of endocrine and neuroendocrine tumours

The most recent WHO classification of endocrine and neuroendocrine tumours has brought about significant changes in the diagnosis and grading of these lesions. For instance, pathologists now have the ability to stratify subsets of thyroid and adrenal neoplasms using various histological features and composite risk assessment models. Moreover, novel recommendations on how to approach endocrine neoplasia involve additional immunohistochemical analyses, and the recognition and implementation of these key markers is essential for modernising diagnostic capabilities. Additionally, an improved understanding of tumour origin has led to the renaming of several entities, resulting in the emergence of terminology not yet universally recognised. The adjustments in nomenclature and prognostication may pose a challenge for the clinical team, and care providers might be eager to engage in a dialogue with the diagnosing pathologist, as treatment guidelines have not fully caught up with these recent changes. Therefore, it is crucial for a surgical pathologist to be aware of the knowledge behind the implementation of changes in the WHO classification scheme. This review article will delve into the most significant diagnostic and prognostic changes related to lesions in the parathyroid, thyroid, adrenal glands and the gastroenteropancreatic neuroendocrine system. Additionally, the author will briefly share his personal reflections on the clinical implementation, drawing from a couple of years of experience with these new algorithms.

Cellular landscape of adrenocortical carcinoma at single-nuclei resolution

Adrenocortical carcinoma (ACC) is a rare yet devastating tumour of the adrenal gland with a molecular pathology that remains incompletely understood. To gain novel insights into the cellular landscape of ACC, we generated single-nuclei RNA sequencing (snRNA-seq) data sets from twelve ACC tumour samples and analysed these alongside snRNA-seq data sets from normal adrenal glands (NAGs). We find the ACC tumour microenvironment to be relatively devoid of immune cells compared to NAG tissues, consistent with known high tumour purity values for ACC as an immunologically "cold" tumour. Our analysis identifies three separate groups of ACC samples that are characterised by different relative compositions of adrenocortical cell types. These include cell populations that are specifically enriched in the most clinically aggressive and hormonally active tumours, displaying hallmarks of reorganised cell mechanobiology and dysregulated steroidogenesis, respectively. We also identified and validated a population of mitotically active adrenocortical cells that strongly overexpress genes POLQ, DIAPH3 and EZH2 to support tumour expansion alongside an LGR4+ progenitor-like or cell-of-origin candidate for adrenocortical carcinogenesis. Trajectory inference suggests the fate adopted by malignant adrenocortical cells upon differentiation is associated with the copy number or allelic balance state of the imprinted DLK1/MEG3 genomic locus, which we verified by assessing bulk tumour DNA methylation status. In conclusion, our results therefore provide new insights into the clinical and cellular heterogeneity of ACC, revealing how genetic perturbations to healthy adrenocortical renewal and zonation provide a molecular basis for disease pathogenesis.

Evaluating the role of aldosterone synthesis on adrenal cell fate

Hypertension affects one-third of the adult population worldwide, with primary aldosteronism (PA) accounting for at least 5-10% of these cases. The aldosterone synthase enzyme (CYP11B2) plays a pivotal role in PA manifestation, as increased expression of CYP11B2 leads to excess aldosterone synthesis. Physiological expression of CYP11B2 in humans is normally limited to cells of the adrenal zona glomerulosa under tight homeostatic regulation. In PA, however, there are CYP11B2-positive lesions in the adrenal cortex that autonomously secrete aldosterone, highlighting the dysregulation of adrenal cortex zonation and function as a key aspect of PA pathogenesis. Thus, this review aims to summarize the development of the adrenal glands, the key regulators of adrenal cortex homeostasis, and the dysregulation of this homeostasis. It also discusses the development of CYP11B2 inhibitors for therapeutic use in patients with hypertension, as well as the current knowledge of the effects of CYP11B2 inhibition on adrenal cortex homeostasis and cell fate. Understanding the control of adrenal cell fate may offer valuable insights into both the pathogenesis of PA and the development of alternative treatment approaches for PA.

Practical consensus for the treatment and follow-up of primary aldosteronism: a multidisciplinary consensus document

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension and is associated with a higher cardiometabolic risk than essential hypertension. The aim of this consensus is to provide practical clinical recommendations for its surgical and medical treatment, pathology study and biochemical and clinical follow-up, as well as for the approach in special situations like advanced age, pregnancy and chronic kidney disease, from a multidisciplinary perspective, in a nominal group consensus approach of experts from the Spanish Society of Endocrinology and Nutrition (SEEN), Spanish Society of Cardiology (SEC), Spanish Society of Nephrology (SEN), Spanish Society of Internal Medicine (SEMI), Spanish Radiology Society (SERAM), Spanish Society of Vascular and Interventional Radiology (SERVEI), Spanish Society of Laboratory Medicine (SEQC(ML)), Spanish Society of Anatomic-Pathology and Spanish Association of Surgeons (AEC).

Mild autonomous cortisol secretion: pathophysiology, comorbidities and management approaches

The majority of incidentally discovered adrenal tumours are benign adrenocortical adenomas and the prevalence of adrenocortical adenomas is around 1-7% on cross-sectional abdominal imaging. These can be non-functioning adrenal tumours or they can be associated with autonomous cortisol secretion on a spectrum that ranges from rare clinically overt adrenal Cushing syndrome to the much more prevalent mild autonomous cortisol secretion (MACS) without signs of Cushing syndrome. MACS is diagnosed (based on an abnormal overnight dexamethasone suppression test) in 20-50% of patients with adrenal adenomas. MACS is associated with cardiovascular morbidity, frailty, fragility fractures, decreased quality of life and increased mortality. Management of MACS should be individualized based on patient characteristics and includes adrenalectomy or conservative follow-up with treatment of associated comorbidities. Identifying patients with MACS who are most likely to benefit from adrenalectomy is challenging, as adrenalectomy results in improvement of cardiovascular morbidity in some, but not all, patients with MACS. Of note, diagnosis and management of patients with bilateral MACS is especially challenging. Current gaps in MACS clinical practice include a lack of specific biomarkers diagnostic of MACS-related health outcomes and a paucity of clinical trials demonstrating the efficacy of adrenalectomy on comorbidities associated with MACS. In addition, little evidence exists to demonstrate the efficacy and safety of long-term medical therapy in patients with MACS.

Comprehensive genomic analysis of adrenocortical carcinoma reveals genetic profiles associated with patient survival

BACKGROUND

Adrenocortical carcinoma (ACC) is one of the most lethal endocrine malignancies and there is a lack of clinically useful markers for prognosis and patient stratification. Therefore our aim was to identify clinical and genetic markers that predict outcome in patients with ACC.

METHODS

Clinical and genetic data from a total of 162 patients with ACC were analyzed by combining an independent cohort consisting of tumors from Yale School of Medicine, Karolinska Institutet, and Düsseldorf University (YKD) with two public databases [The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO)]. We used a novel bioinformatical pipeline combining differential expression and messenger RNA (mRNA)- and DNA-dependent survival. Data included reanalysis of previously conducted whole-exome sequencing (WES) for the YKD cohort, WES and RNA data for the TCGA cohort, and RNA data for the GEO cohort.

RESULTS

We identified 3903 significant differentially expressed genes when comparing ACC and adrenocortical adenoma, and the mRNA expression levels of 461/3903 genes significantly impacted survival. Subsequent analysis revealed 45 of these genes to be mutated in patients with significantly worse survival. The relationship was significant even after adjusting for stage and age. Protein-protein interaction showed previously unexplored interactions among many of the 45 proteins, including the cancer-related proteins DNA polymerase delta 1 (POLD1), aurora kinase A (AURKA), and kinesin family member 23 (KIF23). Furthermore 14 of the proteins had significant interactions with TP53 which is the most frequently mutated gene in the germline of patients with ACC.

CONCLUSIONS

Using a multiparameter approach, we identified 45 genes that significantly influenced survival. Notably, many of these genes have protein interactions not previously implicated in ACC. These findings may lay the foundation for improved prognostication and future targeted therapies.

Bilateral Nephrectomy for Resistant Hypertension and Secondary Aldosteronism in a Hemodialysis Patient: A Case Report

A 42-year-old Japanese woman with end-stage renal failure due to hypertension presented with a systolic blood pressure of 160-200 mmHg despite treatment with 4 different antihypertensive agents. The plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were elevated. Adrenal vein sampling suggested bilateral excessive aldosterone secretion, whereas adrenocortical scintigraphy showed right-dominant accumulation. Open bilateral nephrectomy and right adrenalectomy improved the systolic blood pressure, PAC, and PRA. A pathological examination revealed zona glomerulosa hyperplasia but not microaldosteronoma. This report shows that bilateral nephrectomy, not unilateral adrenalectomy, is a potentially effective treatment option for resistant hypertension with an elevated renin-angiotensin-aldosterone system in hemodialysis patients.

The predictors of long-term outcomes after targeted therapy for primary Aldosteronism

Unilateral primary aldosteronism is thought to be a surgically curable disease, and unilateral adrenalectomy is the mainstay treatment. The Primary Aldosteronism Surgical Outcome (PASO) consensus was developed to assess clinical and biochemical outcomes to standardize the classification of surgical outcomes. However, fewer than half of patients are cured of hypertension after adrenalectomy; therefore, preoperative patient counseling and evaluation might be necessary. Moreover, current studies show that genetic mutations and histopathology classification are associated with the treatment outcome. The Task Force of Taiwan PA recommends using a specific scoring system, including the PASO score and nomogram-based preoperative score, to predict the clinical outcome before adrenalectomy. Herein, we discuss the associations of current histopathological classification and specific somatic gene mutations with clinical outcomes after surgery.

Molecular pathology of endocrine gland tumors: genetic alterations and clinicopathologic relevance

Tumors of the endocrine glands are common. Knowledge of their molecular pathology has greatly advanced in the recent past. This review covers the main molecular alterations of tumors of the anterior pituitary, thyroid and parathyroid glands, adrenal cortex, and adrenal medulla and paraganglia. All endocrine gland tumors enjoy a robust correlation between genotype and phenotype. High-throughput molecular analysis demonstrates that endocrine gland tumors can be grouped into molecular groups that are relevant from both pathologic and clinical point of views. In this review, genetic alterations have been discussed and tabulated with respect to their molecular pathogenetic role and clinicopathologic implications, addressing the use of molecular biomarkers for the purpose of diagnosis and prognosis and predicting response to molecular therapy. Hereditary conditions that play a key role in determining predisposition to many types of endocrine tumors are also discussed.

Feasibility of spectral CT-derived extracellular volume fraction for differentiating aldosterone-producing from nonfunctioning adrenal nodules

OBJECTIVE

To assess the feasibility of spectral CT-derived extracellular volume (ECV) for differentiating aldosterone-producing nodules (APN) from nonfunctioning adrenal nodules (NFN).

METHODS

Sixty-nine patients with biochemically and histologically confirmed unilateral APN (34) and NFN (35) as well as 23 patients with bilateral APN (19) and NFN (27) confirmed biochemically and by adrenal vein sampling (AVS) were enrolled in this retrospective study from October 2020 to April 2022. All patients underwent contrast-enhanced spectral CT of the adrenal glands with a 10-min delayed phase. The haematocrit level was measured within 2 days of CT. An iodine density map was derived from the delayed CT. The ECV fractions of the APN and NFN were calculated and compared in the test cohort of 69 patients with unilateral adrenal nodules. The optimal cut-off value was determined to evaluate the diagnostic efficacy of the ECV fraction for differentiating APN from NFN in the validation cohort of 23 patients with bilateral adrenal nodules.

RESULTS

The ECV fractions of the APN (11.17 ± 4.57%) were significantly lower (p < 0.001) than that of the NFN (24.79 ± 6.01%) in the test cohort. At cut-off ECV value of 17.16%, the optimal area under the receiver operating characteristic curve was 0.974 (95% confidence interval: 0.942-1) with 91.4% sensitivity, 93.9% specificity, and 92.8% accuracy in the test cohort and 89.5% sensitivity, 96.3% specificity, and 93.5% accuracy in the validation cohort for differentiating APN from NFN.

CONCLUSION

The spectral CT-derived ECV fraction can differentiate APN from NFN with high diagnostic performance.

CLINICAL RELEVANCE STATEMENT

Spectral CT-derived extracellular volume fraction could accurately differentiate between adrenal aldosterone-producing nodules and nonfunctioning nodules. It might serve as a noninvasive alternative to adrenal vein sampling in primary aldosteronism patients with bilateral adrenal nodules.

KEY POINTS

• Conventional CT cannot differentiate aldosterone-producing adrenal nodules from nonfunctioning nodules. • Extracellular volume of adrenal aldosterone-producing nodules was significantly lower than that of nonfunctioning nodules and normal adrenal glands. It can accurately differentiate between aldosterone-producing and nonfunctioning adrenal nodules. • Extracellular volume may be a novel, noninvasive biomarker alternative to adrenal vein sampling for determining the functional status of bilateral adrenal nodules in patients with primary aldosteronism.

Advances in translational research of the rare cancer type adrenocortical carcinoma

Adrenocortical carcinoma is a rare malignancy with an annual worldwide incidence of 1-2 cases per 1 million and a 5-year survival rate of <60%. Although adrenocortical carcinoma is rare, such rare cancers account for approximately one third of patients diagnosed with cancer annually. In the past decade, there have been considerable advances in understanding the molecular basis of adrenocortical carcinoma. The genetic events associated with adrenocortical carcinoma in adults are distinct from those of paediatric cases, which are often associated with germline or somatic TP53 mutations and have a better prognosis. In adult primary adrenocortical carcinoma, the main somatic genetic alterations occur in genes that encode proteins involved in the WNT-β-catenin pathway, cell cycle and p53 apoptosis pathway, chromatin remodelling and telomere maintenance pathway, cAMP-protein kinase A (PKA) pathway or DNA transcription and RNA translation pathways. Recently, integrated molecular studies of adrenocortical carcinomas, which have characterized somatic mutations and the methylome as well as gene and microRNA expression profiles, have led to a molecular classification of these tumours that can predict prognosis and have helped to identify new therapeutic targets. In this Review, we summarize these recent translational research advances in adrenocortical carcinoma, which it is hoped could lead to improved patient diagnosis, treatment and outcome.

Revising the Roles of Aldosterone in Vascular Physiology and Pathophysiology: From Electocortin to Baxdrostat

Aldosterone was initially identified as a hormone primarily related to regulation of fluid and electrolyte homeostasis. However, over the past 20 years there has been an increasing appreciation of its role in regulation of vascular function and pathophysiology in the setting of hypertension, atherosclerosis, and heart failure. This review highlights recent advances in our understanding the biology of aldosterone as it relates to the pathophysiology and the management of vascular disease-especially related to hypertension. The review focuses on 3 key areas: 1) advances in our understanding of the cellular mechanisms by which aldosterone mediates its cellular effects, 2) identification of the hidden epidemic of aldosteronism as a mediator of hypertension, and 3) appreciating new therapeutic advances in the clinical pharmacology of aldosterone inhibition in cardiovascular and renal disease.

Expression of Amine Oxidase Proteins in Adrenal Cortical Neoplasm and Pheochromocytoma

We delved into the expression of amine oxidase family proteins and their potential significance in adrenal gland neoplasm. Tissue microarrays were prepared for 132 cases of adrenal cortical neoplasm (ACN) consisting of 115 cases of adrenal cortical adenoma (ACA), 17 cases of adrenal cortical carcinoma (ACC), and 163 cases of pheochromocytoma (PCC). Immunohistochemical stainings for MAOA, MAOB, LOX, and AOC3 were performed to evaluate the H-scores and compare them with clinicopathological parameters. The H-scores of MAOA (T; p = 0.005) and MAOB (T; p = 0.006) in tumor cells (T) were high in ACN, whereas LOX (T, S; p < 0.001) in tumor and stromal cells (S) and AOC3 (T; p < 0.001) were higher in PCC. In stromal cells, MAOA (S; p < 0.001) and AOC3 (S; p = 0.010) were more expressed in ACA than in ACC. MAOB (S) in PCC showed higher H-scores when the grading of adrenal pheochromocytoma and paraganglioma (GAPP) score was 3 or higher (p = 0.027). In the univariate analysis, low MAOA expression in stromal cells of ACN was associated with shorter overall survival (p = 0.008). In conclusion, monoamine oxidase proteins revealed differences in expression between ACN and PCC and also between benign and malignant cells.

Pediatric Adrenocortical Neoplasms: A Study Comparing Three Histopathological Scoring Systems

Adrenocortical neoplasms are rare in childhood. Their histopathological categorization into benign and malignant is often challenging, impacting further management. While the AFIP/Wieneke scoring system is widely used for the prognostic classification of these tumors, it has limitations. Few other tumor scoring systems have evolved over the past few years. These have been validated in adults but not yet in pediatric patients. We evaluated a cohort of pediatric adrenocortical neoplasms to assess the applicability of AFIP/Wieneke criteria and the recently introduced Helsinki score and reticulin algorithm in predicting clinical outcomes. A tumor was considered 'clinically aggressive' in the presence of any of the following: metastases, recurrence, progressive disease, or death due to disease. Cases without any such event were considered 'clinically good'. Event-free survival time was the duration from the date of clinical presentation to any post-operative adverse event. For overall survival analysis, the endpoint was either the last follow-up or death due to disease.Using ROC curve analysis, the obtained cut-off Helsinki score of 24 could stratify the cases into two prognostically relevant groups. Survival analysis showed significant differences in the event-free and overall survival of these two groups of patients, validating the proposed cut-off. None of the three histopathological scoring systems could predict an unfavorable outcome with 100% accuracy. All showed a sensitivity of ≥ 80%, with the reticulin algorithm achieving 100% sensitivity. The specificity and accuracy of the AFIP/Wieneke criteria were the lowest (62.5% and 73.08%, respectively). While the Helsinki score (at the cut-off score of 24) and the reticulin algorithm had similar accuracy rates (80.77%, and 80%, respectively), the specificity of the former was higher (81.25%) than the latter (68.75%). A separate analysis revealed that the Ki-67 index at a cut-off of 18% had a sensitivity of 80% and a specificity of 81.25% for predicting an unfavorable outcome.

Morphological Harbingers of ARMC5-Pathogenic Variant-Related Bilateral Macronodular Adrenocortical Disease

Bilateral macronodular adrenocortical disease (BMAD) is a neoplastic disease associated with a high frequency of germline disease. Armadillo repeat containing 5 (ARMC5) pathogenic variants (PVs) have not been widely studied to determine the morphological and immunohistochemical characteristics of BMAD. We carried out a detailed morphologic review of 22 surgical specimens excised from patients with BMAD and compared them with PV of ARMC5 (PV + , n = 14) and those without (PV - , n = 8), and further comparing them with a control group of adrenals excised from patients with renal cancer (n = 11). No patients presented with a genetic syndrome related to BMAD. Overt Cushing's syndrome was present in 12/22 patients, 10 PV + and 2 PV - (p = 0.074). We also evaluated the expression of Ki-67, BCL-2, BAX, p53, CYP11B1, and ARMC5 protein. The pseudo-glandular and trabecular architectural patterns were strongly associated with the PV + group (both p < 0.001), as well as capsular extrusion (p < 0.001). There was no predictive value in the distinction of ARMC5 variants in Hsiao subtyping. ARMC5 diffuse cytoplasmic staining was observed in all 11 control samples. The ARMC5 expression was significantly lower in BMAD than in the control group (p < 0.001). In all the specimens, expression of BCL-2 was identified only in the medulla, and expression of BAX was observed in adrenocortical cells. CYP11B1 diffuse immunoexpression was identified in all the specimens of BMAD and in the fasciculata zone in the control group. The mitotic count and Ki-67 proliferation index was very low in all three groups (controls, PV + , and PV - BMAD). None of the specimens stained positive for the p53 protein. Although our series is limited, the presence of pseudo-glandular and/or trabecular patterns and capsular extrusion indicated the presence of pathogenic variants of ARMC5 in BMAD. The gland enlargement does not seem to be related to the increase of mitotic count or a higher proliferation index (Ki-67).

Impact of Morphology in the Genotype and Phenotype Correlation of Bilateral Macronodular Adrenocortical Disease (BMAD): A Series of Clinicopathologically Well-Characterized 35 Cases

Bilateral macronodular adrenocortical disease (BMAD) is characterized by the development of adrenal macronodules resulting in a pituitary-ACTH independent Cushing's syndrome. Although there are important similarities observed between the rare microscopic descriptions of this disease, the small series published are not representative of the molecular and genetic heterogenicity recently described in BMAD. We analyzed the pathological features in a series of BMAD and determined if there is correlation between these criteria and the characteristics of the patients. Two pathologists reviewed the slides of 35 patients who underwent surgery for suspicion of BMAD in our center between 1998 and 2021. An unsupervised multiple factor analysis based on microscopic characteristics divided the cases into 4 subtypes according to the architecture of the macronodules (containing or not round fibrous septa) and the proportion of the different cell types: clear, eosinophilic compact, and oncocytic cells. The correlation study with genetic revealed subtype 1 and subtype 2 are associated with the presence of ARMC5 and KDM1A pathogenic variants, respectively. By immunohistochemistry, all cell types expressed CYP11B1 and HSD3B1. HSD3B2 staining was predominantly expressed by clear cells whereas CYP17A1 staining was predominant on compact eosinophilic cells. This partial expression of steroidogenic enzymes may explain the low efficiency of cortisol production in BMAD. In subtype 1, trabeculae of eosinophilic cylindrical cells expressed DAB2 but not CYP11B2. In subtype 2, KDM1A expression was weaker in nodule cells than in normal adrenal cells; alpha inhibin expression was strong in compact cells. This first microscopic description of a series of 35 BMAD reveals the existence of 4 histopathological subtypes, 2 of which are strongly correlated with the presence of known germline genetic alterations. This classification emphasizes that BMAD has heterogeneous pathological characteristics that correlate with some genetic alterations identified in patients.

FLCN-Driven Functional Adrenal Cortical Carcinoma with High Mitotic Tumor Grade: Extending the Endocrine Manifestations of Birt-Hogg-Dubé Syndrome

Adrenal cortical carcinoma is an aggressive and rare malignancy of steroidogenic cells of the adrenal gland. Most adult adrenal cortical carcinomas are sporadic, but a small fraction may be associated with inherited tumor syndromes, such as Li-Fraumeni, multiple endocrine neoplasia 1, Lynch syndrome, and Beckwith-Wiedemann syndrome, as well as isolated case reports of non-syndromic manifestations occurring in the context of other pathogenic germline variants. Birt-Hogg-Dubé (BHD) is a rare autosomal dominant syndrome caused by germline pathogenic variants in the FLCN gene. BHD syndrome causes a constellation of symptoms, including cutaneous manifestations, pulmonary cysts and pneumothorax, and risk of renal tumors. With the exception of a single case of adrenal cortical carcinoma, very few reports on the occurrence of adrenal cortical neoplasia in patients with BHD syndrome have been described. However, information on variant allele fraction in the tumor was not available in the index case, which precludes any mechanism supporting loss of heterozygosity. Here we present a case of an adult-onset adrenal cortical carcinoma in a 50-year-old female, found to harbor a germline likely pathogenic variant in the FLCN gene, denoted as c.694C > T (p.Gln232Ter). Genetic testing on the tumor revealed the same FLCN variant at an allele fraction of 83%, suggesting a contributory role to the pathogenesis of the adrenal cortical carcinoma. This case further supports the expansion of the clinical presentation and tumor spectrum of BHD syndrome and the need to consider germline FLCN testing in the clinical genetic workup of patients with adrenal cortical carcinomas.

Histopathologic Features of Adrenal Cortical Carcinoma

Adrenal cortical carcinoma (ACC) is a rare and aggressive malignancy that poses challenging issues regarding the diagnostic workup. Indeed, no presurgical technique or clinical parameters can reliably distinguish between adrenal cortical adenomas, which are more frequent and have a favorable outcome, and ACC, and the final diagnosis largely relies on histopathologic analysis of the surgical specimen. However, even the pathologic assessment of malignancy in an adrenal cortical lesion is not straightforward and requires a combined evaluation of multiple histopathologic features. Starting from the Weiss score, which was developed in 1984, several histopathologic scoring systems have been designed to tackle the difficulties of ACC diagnosis. Dealing with specific histopathologic variants (eg, Liss-Weiss-Bisceglia scoring system for oncocytic ACC) or patient characteristics (eg, Wieneke index in the pediatric setting), these scores remarkably improved the diagnostic workup of ACC and its subtypes. Nevertheless, cases with misleading features or discordant correlations between pathologic findings and clinical behavior still occur. Owing to multicentric collaborative studies integrating morphologic features with ancillary immunohistochemical markers and molecular analysis, ACC has eventually emerged as a multifaceted, heterogenous malignancy, and, while innovative and promising approaches are currently being tested, the future clinical management of patients with ACC will mainly rely on personalized medicine and target-therapy protocols. At the dawn of the new Fifth World Health Organization classification of endocrine tumors, this review will tackle ACC from the pathologist's perspective, thus focusing on the main available diagnostic, prognostic, and predictive tissue-tethered features and biomarkers and providing relevant clinical and molecular correlates.

Advances in Adrenal and Extra-adrenal Paraganglioma: Practical Synopsis for Pathologists

Adrenal paraganglioma (or "pheochromocytoma") and extra-adrenal paraganglioma, collectively abbreviated PPGL, are rare but spectacular nonepithelial neuroendocrine neoplasms. These are the most inheritable neoplasia of all, with a metastatic potential in a varying degree. As of such, these lesions demand careful histologic, immunohistochemical, and genetic characterization to provide the clinical team with a detailed report taking into account the anticipated prognosis and risk of syndromic/inherited disease. While no histologic algorithm, immunohistochemical biomarker, or molecular aberration single-handedly can identify potentially lethal cases upfront, the combined analysis of various risk parameters may stratify PPGL patients more stringently than previously. Moreover, the novel 2022 WHO Classification of Endocrine and Neuroendocrine Tumors also brings some new concepts into play, not least the reclassification of special neuroendocrine neoplasms (cauda equina neuroendocrine tumor and composite gangliocytoma/neuroma-neuroendocrine tumor) previously thought to belong to the spectrum of PPGL. This review focuses on updated key diagnostic and prognostic concepts that will aid when facing this rather enigmatic tumor entity in clinical practice.

Metabolomics-A Tool to Find Metabolism of Endocrine Cancer

Clinical endocrinology entails an understanding of the mechanisms involved in the regulation of tumors that occur in the endocrine system. The exact cause of endocrine cancers remains an enigma, especially when discriminating malignant lesions from benign ones and early diagnosis. In the past few years, the concepts of personalized medicine and metabolomics have gained great popularity in cancer research. In this systematic review, we discussed the clinical metabolomics studies in the diagnosis of endocrine cancers within the last 12 years. Cancer metabolomic studies were largely conducted using nuclear magnetic resonance (NMR) and mass spectrometry (MS) combined with separation techniques such as gas chromatography (GC) and liquid chromatography (LC). Our findings revealed that the majority of the metabolomics studies were conducted on tissue, serum/plasma, and urine samples. Studies most frequently emphasized thyroid cancer, adrenal cancer, and pituitary cancer. Altogether, analytical hyphenated techniques and chemometrics are promising tools in unveiling biomarkers in endocrine cancer and its metabolism disorders.

The Entity of Connshing Syndrome: Primary Aldosteronism with Autonomous Cortisol Secretion

Connshing syndrome (CoSh) (adrenal-related synchronous aldosterone (A) and cortisol (C) excess) represents a distinct entity among PA (primary hyperaldosteronisms) named by W. Arlt et al. in 2017, but the condition has been studied for more than 4 decades. Within the last few years, this is one of the most dynamic topics in hormonally active adrenal lesions due to massive advances in steroids metabolomics, molecular genetics from CYP11B1/B2 immunostaining to genes constellations, as well as newly designated pathological categories according to the 2022 WHO classification. In gross, PA causes 4-10% of all high blood pressure (HBP) cases, and 20% of resistant HBP; subclinical Cushing syndrome (SCS) is identified in one-third of adrenal incidentalomas (AI), while CoSh accounts for 20-30% to 77% of PA subjects, depending on the tests used to confirm autonomous C secretion (ACS). The clinical picture overlaps with PA, hypercortisolemia being mild. ACS is suspected in PA if a more severe glucose and cardiovascular profile is identified, or there are larger tumours, ACS being an independent factor risk for kidney damage, and probably also for depression/anxiety and osteoporotic fractures. It seems that one-third of the PA-ACS group harbours mutations of C-related lines like PRKACA and GNAS. A novel approach means we should perform CYP11B2/CYP11B1 immunostaining; sometimes negative aldosteronoma for CYP11B1 is surrounded by micronodules or cell clusters with positive CYP11B1 to sustain the C excess. Pitfalls of hormonal assessments in CoSh include the index of suspicion (check for ACS in PA patients) and the interpretation of A/C ratio during adrenal venous sample. Laparoscopic adrenalectomy is the treatment of choice. Post-operative clinical remission rate is lower in CoSh than PA. The risk of clinically manifested adrenal insufficiency is low, but a synthetic ACTH stimulating testing might help to avoid unnecessary exposure to glucocorticoids therapy. Finally, postponing the choice of surgery may impair the outcome, having noted that long-term therapy with mineralocorticoids receptors antagonists might not act against excessive amounts of C. Awareness of CoSh improves management and overall prognosis.

Clinical analysis of the etiological spectrum of bilateral adrenal lesions: A large retrospective, single-center study

PURPOSE

To investigate the clinical characteristics, endocrinological function, and etiology of bilateral adrenal lesions in hospitalized patients.

METHODS

A retrospective study of 777 patients with bilateral adrenal lesions was conducted at the Chinese People's Liberation Army General Hospital between January 2013 and January 2018. Patients' demographic features, hormonal profiles, imaging findings, and histopathological findings were reviewed from database records.

RESULTS

Of the 777 patients with bilateral adrenal lesions, 495 were men. The mean age at diagnosis was 52.0 ± 13.0 years. Overall, 511 (65.8%) cases were benign, followed by adrenal metastases (n = 224, 28.8%), pheochromocytoma (n = 26, 3.3%), adrenal lymphoma (n = 9, 1.2%), and adrenal corticocarcinoma (ACC; n = 7, 0.9%). Hormonal evaluation revealed that 34.3% of bilateral adrenal lesions were functional. The primary etiologies of functional lesions were primary aldosteronism (16.6%, 129/777), and primary bilateral macronodular adrenocortical hyperplasia (PBMAH; 8.8%, 68/777). Patients with lymphoma and metastases were significantly older than those with benign nonfunctional lesions (60.4 ± 11.0 years vs. 54.5 ± 10.4 years and 57.9 ± 10.8 years vs. 54.5 ± 10.4 years, respectively; both P < 0.001). Lesions in patients with adrenal lymphoma, ACC, pheochromocytoma, metastases, congenital adrenal hyperplasia, tuberculosis, and Cushing's syndrome were significantly larger than benign nonfunctional lesions (all P < 0.001).

CONCLUSION

Benign adrenal lesions and metastases from the lungs are the most common causes of bilateral adrenal lesions. Primary aldosteronism and PBMAH are the most prevalent functional lesions. Moreover, patients with lymphoma or metastases are older and their masses are larger.

MicroRNAs and Long Non-Coding RNAs in Adrenocortical Carcinoma

Non-coding RNAs (ncRNAs) are a type of genetic material that do not encode proteins but regulate the gene expression at an epigenetic level, such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). The role played by ncRNAs in many physiological and pathological processes has gained attention during the last few decades, as they might be useful in the diagnosis, treatment and management of several human disorders, including endocrine and oncological diseases. Adrenocortical carcinoma (ACC) is a rare and aggressive endocrine cancer, still characterized by high mortality and morbidity due to both endocrine and oncological complications. Despite the rarity of this disease, recently, the role of ncRNA has been quite extensively evaluated in ACC. In order to better explore the role of the ncRNA in human ACC, this review summarizes the current knowledge on ncRNA dysregulation in ACC and its potential role in the diagnosis, treatment, and management of this tumor.

Prognostic Utility of the Ki-67 Labeling Index in Follicular Thyroid Tumors: a 20-Year Experience from a Tertiary Thyroid Center

Follicular thyroid tumors pose a diagnostic challenge on the preoperative level, as the discrimination between follicular thyroid carcinoma (FTC) and adenoma (FTA) demands careful histopathological investigation. Moreover, prognostication of FTCs is mostly based on tumor size and extent of invasive properties, while immunohistochemical markers pinpointing high-risk cases are lacking. We have routinely established a Ki-67 labeling index for follicular thyroid tumors since 1999. To assess the potential value of Ki-67 as an adjunct tool to (1) correctly separate FTCs from FTAs and (2) help identify poor-prognosis FTCs, we collected histopathological and clinical data from 818 follicular thyroid tumors with a histological Ki-67 labeling index established in clinical routine practice (516 FTAs, 252 FTCs, and 50 follicular thyroid tumors of uncertain malignant potential (FT-UMPs)). The Ki-67 labeling index was higher in FTCs (mean 5.8%) than in FTAs (mean 2.6%) (P < 0.001), and a receiver operating characteristic curve analysis revealed a cut-off value of 4% to separate FTC from FTA with a sensitivity and specificity of 65% and 83%, respectively. Similarly, a Ki-67 labeling index above 4% was found to identify FTCs that later metastasized from clinically indolent FTCs with a sensitivity and specificity of 80% and 48%, respectively. Ki-67 constituted an independent predictor of future FTC metastases/recurrence and death of disease, and a value > 4% was a reliable prognostic marker within individual pT staging groups. We conclude that Ki-67 is a potentially valuable marker for the prognostication of FTCs, and future implementation in the histopathological assessments of follicular thyroid tumors could be beneficial if reproduced in international series.

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.

Mixed corticomedullary tumor of the adrenal gland

Mixed corticomedullary tumor (MCMT) of the adrenal gland is an extremely rare tumor characterized by an admixture of steroidogenic cells and chromaffin cells in a single tumor mass simultaneously producing adrenocortical hormones and catecholamines; it is associated with ectopic adrenocorticotropic hormone (ACTH) in some cases. We reviewed and summarized clinicopathological data of 28 MCMTs, including four metastatic tumors in 26 previous reports. These reports included 21 females and 7 males, and the average tumor sizes were 4.8 ± 2.5 cm and 12.6 ± 6.4 cm in the non-metastatic and metastatic groups, respectively (P<0.001). The clinical manifestations and laboratory data were as follows: Cushing or subclinical Cushing syndrome, 58% (14/24); hypertension, 71% (17/24); elevated adrenocortical hormones, 75% (18/24); elevated catecholamines, 75% (18/24); and ectopic ACTH, 71% (10/14). All four patients with metastatic MCMTs had poor prognoses and elevated adrenocortical hormone levels; however, only two patients had elevated catecholamine levels. Immunohistochemistry was essential for the pathologic diagnosis of MCMTs. In this study, using an improved technique, we detected ectopic ACTH-producing cells in the same paraffin-embedded sections reported to be negative in our previous reports. As MCMT is composed of cells with embryologically different origins, its pathogenesis has been explained by various hypotheses. We compared MCMT to the adrenal gland of birds and the early stage of human fetuses, in which nests of chromaffin cells and steroidogenic cells admix without the formation of cortex and medulla. MCMT is characterized by the immaturity of organogenesis and might be classified as an adrenal embryonal tumor.

KDM1A inactivation causes hereditary food-dependent Cushing syndrome

PURPOSE

This study aimed to investigate the genetic cause of food-dependent Cushing syndrome (FDCS) observed in patients with primary bilateral macronodular adrenal hyperplasia (PBMAH) and adrenal ectopic expression of the glucose-dependent insulinotropic polypeptide receptor. Germline ARMC5 alterations have been reported in about 25% of PBMAH index cases but are absent in patients with FDCS.

METHODS

A multiomics analysis of PBMAH tissues from 36 patients treated by adrenalectomy was performed (RNA sequencing, single-nucleotide variant array, methylome, miRNome, exome sequencing).

RESULTS

The integrative analysis revealed 3 molecular groups with different clinical features, namely G1, comprising 16 patients with ARMC5 inactivating variants; G2, comprising 6 patients with FDCS with glucose-dependent insulinotropic polypeptide receptor ectopic expression; and G3, comprising 14 patients with a less severe phenotype. Exome sequencing revealed germline truncating variants of KDM1A in 5 G2 patients, constantly associated with a somatic loss of the KDM1A wild-type allele on 1p, leading to a loss of KDM1A expression both at messenger RNA and protein levels (P = 1.2 × 10^-12 and P < .01, respectively). Subsequently, KDM1A pathogenic variants were identified in 4 of 4 additional index cases with FDCS.

CONCLUSION

KDM1A inactivation explains about 90% of FDCS PBMAH. Genetic screening for ARMC5 and KDM1A can now be offered for most PBMAH operated patients and their families, opening the way to earlier diagnosis and improved management.

Dermatological and endocrine elements in Carney complex (Review)

Carney complex (CΝC) is a very rare, autosomal dominant, hereditary syndrome. Seventy percent of individuals with CNC have germline inactivating or deleting mutations of the CNC1 gene [currently known as protein kinase cAMP-dependent type I regulatory subunit α (PRKAR1A), located at the 17q22-24 chromosome level], with 30% of cases presenting with phosphodiesterase gene mutations. A member of the lentiginosis family, dermatological features include: skin pigmentation, cutaneous/mucosal myxomas, usually diagnosed by the age of 20 years (neonatal presentation is exceptional, requiring a meticulous differential diagnosis). Melanocyte-derived tumors such as epithelioid blue nevi (with different levels of pigmentation) and pigmented epithelioid melanocytoma (previously 'animal-type melanoma') are often found. Myxomas, mesenchymal tumors with mostly a benign pattern, may be recurrent. Primary cutaneous melanotic schwannoma are atypical, while non-skin sites are frequent. Corticotropinomas or somatotropinomas are part of the hereditary syndrome-related pituitary adenomas (representing 5% of all). Primary pigmented nodular adrenocortical disease involves bilateral cortical hyperplasia causing Cushing syndrome (CS) at an earlier age than non-CNC cases; osteoporotic fractures seem more prevalent compare to CS of other etiologies. Typically benign, a few cases of adrenocortical carcinoma have been identified. A total of 5% of familial non-medullary thyroid cancer is syndromic, also including CNC. CNC-related thyroid frame includes: hyperthyroidism, follicular hyperplasia/adenomas, follicular carcinoma (usually aggressive, bilateral or multifocal). Large cell calcifying Sertoli cell tumors of the testes have malignant behavior in adults; in children these may induce precocious puberty. Two particular mammary tumors are found: myxoid fibroadenomas and breast myxomatosis. Cutaneous/subcutaneous lesions, pigmented or not, or any focal swelling of non-identified cause needs careful examination, since dermatological elements are among the earliest and most discernable by which to detect lesions in CNC, a systemic condition with multi-level endocrine involvement.

Second-Generation Neuroendocrine Immunohistochemical Markers: Reflections from Clinical Implementation

Simple Summary

Neuroendocrine tumors are a collection of neoplastic lesions arising in cells with traits similar to hormone-producing and nerve cells with the ability to secrete peptide hormones using an intricate vesicle transportation system. From a clinical standpoint, neuroendocrine tumors are unique in terms of therapeutic modalities, and a correct diagnosis is therefore imperative in order for the patient to obtain the most efficient treatment. In this process, the pathologist can analyze if the tumor cells express Chromogranin A and Synaptophysin, two proteins associated with the regulation of secretory vesicles. Unfortunately, these markers are not always present in neuroendocrine tumors, and non-neuroendocrine tumors may also occasionally express Chromogranin A or Synaptophysin—making the diagnosis difficult to make for certain cases. Recently, three proteins termed ISL1, INSM1 and Secretagogin were found to be selectively expressed in neuroendocrine cells, and subsequent studies have identified their potential as markers of neuroendocrine differentiation in the clinical setting. In this commentary, the benefits of these novel “second-generation” markers are briefly discussed from a clinical context.

Abstract

When analyzing tumors by histopathology, endocrine pathologists have traditionally been restricted to a few key immunohistochemical markers related to secretory vesicles in order to pinpoint neuroendocrine differentiation—most notably Chromogranin A (CGA) and Synaptophysin (SYP). Although proven of great clinical utility, these markers sometimes exhibit tissue-specific patterns depending on tumor origin, and non-neuroendocrine tumors might sometimes display focal expression. Moreover, CGA and SYP might be partially or totally absent in highly proliferative neuroendocrine carcinomas, making the diagnosis particularly challenging on small biopsies of metastatic lesions with unknown location of the primary tumor. The advent of second-generation neuroendocrine markers ISL LIM Homeobox 1 (ISL1), INSM Transcriptional Repressor 1 (INSM1) and Secretagogin (SECG) have expanded the pathology toolbox considerably, constituting markers that often retain expression even in poorly differentiated neuroendocrine carcinomas. As non-neuroendocrine tumors seldom express these antigens, the specificity of ISL1, INSM1 and SECG make them welcome additions to clinical practice. In this commentary, recent advances of this field as well as initial clinical experiences from a tertiary neuroendocrine center are discussed.