Adrenocortical tumors and insulin resistance: What is the first step?

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.

Hyperandrogenism and Cardiometabolic Risk in Pre- and Postmenopausal Women-What Is the Evidence?

Hyperandrogenism in women, such as polycystic ovary syndrome, ovarian hyperthecosis, congenital adrenal hyperplasia, and androgen-secreting tumors, are all associated with increased prevalence of cardiovascular risk factors that include type 2 diabetes, hypertension, dyslipidemia, and metabolic syndrome. However, it is not clear whether this also implies enhanced risk of cardiovascular disease and mortality. Furthermore, the involvement of obesity and menopausal status for cardiometabolic risk in these women has not been elucidated. Based on the most recent systematic reviews and meta-analyses, this review summarizes the latest scientific evidence. To conclude, hyperandrogenism in premenopausal women is associated with enhanced prevalence of cardiovascular risk factors, as well as increased risk of cardiovascular disease and mortality, independently of body mass index. In contrast, elevated cardiovascular risk factors and increased risk of myocardial infarction and stroke in hyperandrogenic postmenopausal women are dependent on obesity. Furthermore, the overall risk of cardiovascular disease and coronary artery disease in hyperandrogenic postmenopausal women is similar to controls. The reason for a reduced cardiometabolic risk after menopause in hyperandrogenic women compared to nonhyperandrogenic women is not clear. It can be speculated that the difference in endocrine balance and metabolic status between women with and without hyperandrogenism might decrease after menopause because hyperandrogenism usually improves with age, whereas menopausal transition itself is associated with androgen dominance and abdominal obesity. Although we have gained increased knowledge about cardiometabolic risks in women with hyperandrogenism, it must be acknowledged that the quality of data is overall low. More research is needed, especially longer and larger follow-up studies in women with hyperandrogenism of different etiologies and phenotypes.

Cushing's Syndrome in Pregnancy Secondary to Adrenocortical Adenoma: A Case Series and Review

PURPOSE

To present a case series of Cushing's syndrome (CS) during pregnancy caused by adrenocortical adenomas, highlighting clinical features, hormonal assessments and outcomes.

METHODS

We describe five pregnant women with CS, detailing clinical presentations and laboratory findings.

RESULTS

Common clinical features included a full moon face, buffalo back and severe hypertension. Elevated blood cortisol levels with circadian rhythm disruption and suppressed adrenocorticotrophic hormone (ACTH) levels were observed. Imaging revealed unilateral adrenal tumours. Two cases underwent laparoscopic adrenalectomies during the second trimester, while three had postpartum surgery. All required hormone replacement therapy, with postoperative pathological confirmation of adrenocortical adenomas.

CONCLUSION

Diagnosis of CS during pregnancy is challenging due to overlapping features with normal pregnancy: elevated blood cortisol levels and abnormal diurnal rhythm of blood cortisol, suppressed aid diagnosis. Treatment should be individualised due to a lack of explicit optimum therapeutic approaches. Laparoscopic adrenalectomy may be an optimal choice, along with multidisciplinary management including hormone replacement therapy.

Sensitivity of the Neuroendocrine Stress Axis in Metabolic Diseases

Metabolic diseases are prevalent in modern society and have reached pandemic proportions. Metabolic diseases have systemic effects on the body and can lead to changes in the neuroendocrine stress axis, the critical regulator of the body's stress response. These changes may be attributed to rising insulin levels and the release of adipokines and inflammatory cytokines by adipose tissue, which affect hormone production by the neuroendocrine stress axis. Chronic stress due to inflammation may exacerbate these effects. The increased sensitivity of the neuroendocrine stress axis may be responsible for the development of metabolic syndrome, providing a possible explanation for the high prevalence of severe comorbidities such as heart disease and stroke associated with metabolic disease. In this review, we address current knowledge of the neuroendocrine stress axis in response to metabolic disease and discuss its role in developing metabolic syndrome.

Prevalence and incidence of type 2 diabetes mellitus in patients with adrenal incidentalomas: a study of 709 cases

AIM

To evaluate the prevalence and incidence of type 2 diabetes in patients with nonfunctioning adrenal incidentalomas (NFAI) or adrenal incidentalomas (AI) with autonomous cortisol secretion (ACS).

METHODS

In this single-center retrospective study, all patients with adrenal incidentalomas ≥1 cm and ACS or NFAI studied between 2013 and 2020 were included. ACS was defined by a post-dexamethasone suppression test (DST) serum cortisol concentration ≥1.8 μg/dl, in the absence of signs of hypercortisolism, and NFAI was defined as a DST < 1.8 μg/dl without biochemical evidence of hypersecretion of other hormones.

RESULTS

Inclusion criteria were met by 231 patients with ACS and 478 with NFAI. At diagnosis, type 2 diabetes was present in 24.3% of patients. No differences were found in the prevalence of type 2 diabetes (27.7 vs. 22.6%, P = 0.137) between patients with ACS and NFAI. However, fasting plasma glucose values and glycated hemoglobin levels were significantly higher in patients with ACS than with NFAI (112 ± 35.6 vs. 105 ± 29 mg/dl, P = 0.004; and 6.5 ± 1.4 vs. 6.1 ± 0.9%, P = 0.005, respectively). Furthermore, patients with type 2 diabetes had higher urinary free cortisol (P = 0.039) and late-night salivary cortisol levels (P = 0.010) than those without type 2 diabetes. After a median follow-up of 28 months, no differences were found in the incidence of type 2 diabetes between the groups (HR 1.17, 95% 0.52-2.64).

CONCLUSION

Type 2 diabetes was present in one fourth of our cohort. We found no differences in its prevalence or incidence between the groups. However, glycemic control might be worse among diabetic patients with ACS. Higher concentrations of urinary and salivary cortisol were found in patients with than without type 2 diabetes.

Do Non-Functional Adrenal Adenomas Affect Metabolic Profile and Carotid Intima-Media Thickness? A Single Centre Study from Poland

Background: Compared to the general population, among people with adrenal incidentalomas (AIs) the diagnosis of obesity, hypertension, impaired carbohydrate and lipid metabolism is more common. The aformentioned disorders represent typical cardiovascular remodeling risk factors. The study was designed to assess the association between NFAIs, metabolic profile and carotid intima-media thickness (CIMT) as the predictive factor of atherosclerosis. Material: The study included 48 patients with NFAI (16 men, 32 women, mean age 58.6 +/- 9 years) and 44 control participants (15 men, 29 women, mean age 57 +/- 7 years). Both groups were matched for age, gender and BMI. Subjects with history of myocardial infarction, stroke or diabetes mellitus (DM) were excluded. Participants underwent adrenal imaging, biochemical evaluation, and measurement of CIMT. Hormonal evaluation was conducted in AI patients. Results: The NFAI group had significantly higher waist circumference (p < 0.01), higher systolic (p < 0.01) and diastolic blood pressure (p < 0.01), fasting insulin (p = 0.03) and glucose in the 2 h OGTT (p = 0.04) as well as higher CIMT (p < 0.01). Hypertension (p < 0.01) and IGT (p = 0.026) were more common in this group as well. There was a positive correlation between CIMT and cortisol levels in 1 mg dexamethasone suppression test (r = 0.33, p = 0.02). Conclusions: Patients diagnosed with NFAIs, despite normal cortisol inhibition in the 1 mg dexamethasone test, still presented a number of metabolic abnormalities. The assessment of IMT may proove valuable in indicate the presence of early vascular remodelling in asymptomatic patients. The underlying mechanisms of these findings are still unknown, hence further studies are required.

Associations of insomnia with insulin resistance traits: a cross-sectional and Mendelian Randomization study

CONTEXT

Insomnia is associated with insulin resistance (IR) in observational studies, however, whether insomnia is causally associated with IR remains unestablished.

OBJECTIVE

This study aims to estimate the causal associations of insomnia with IR and its related traits.

METHODS

In primary analyses, multivariable regression (MVR) and one-sample Mendelian randomization (1SMR) analyses were performed to estimate the associations of insomnia with IR (triglyceride-glucose [TyG] index and triglyceride to high-density lipoprotein cholesterol [TG/HDL-C] ratio) and its related traits (glucose level, TG, and HDL-C) in UK Biobank. Thereafter, two-sample MR (2SMR) analyses were used to validate the findings from primary analyses. Finally, the potential mediating effects of IR on the pathway of insomnia giving rise to T2D were examined using a two-step MR design.

RESULTS

Across the MVR, 1SMR, and their sensitivity analyses, we found consistent evidence suggesting that more frequent insomnia symptoms were significantly associated with higher values of TyG index (MVR: β = 0.024, P < 2.00E-16; 1SMR: β = 0.343, P < 2.00E-16), TG/HDL-C ratio (MVR: β = 0.016, P = 1.75E-13; 1SMR: β = 0.445, P < 2.00E-16), and TG level (MVR: β = 0.019 log mg/dl, P < 2.00E-16; 1SMR: β = 0.289 log mg/dL, P < 2.00E-16) after Bonferroni adjustment. Similar evidence was obtained by using 2SMR, and mediation analysis suggested that about a quarter (25.21%) of the association between insomnia symptoms and T2D was mediated by IR.

CONCLUSIONS

This study provides robust evidence supporting that more frequent insomnia symptoms are associated with IR and its related traits across different angles. These findings indicate that insomnia symptoms can be served as a promising target to improve IR and prevent subsequent T2D.

Endogenous Cushing's syndrome during pregnancy

Endogenous Cushing's syndrome (CS) is rare during pregnancy, probably because hypercortisolism induces anovulation and infertility. To date, slightly above 200 cases have been reported in the literature. The most frequent etiology of CS diagnosed during gestation is from primary adrenal causes, namely adrenal adenomas and an entity called pregnancy-induced CS. The latter can be secondary to the aberrant adrenal expression of luteinizing hormone/human chorionic gonadotropin receptor (LHCGR) in the adrenal lesions. Diagnosis of CS during pregnancy is extremely challenging, as a consequence of the physiologic hypercortisolism normally present during pregnancy. Assessment of excess cortisol production tests should be interpreted cautiously using adapted upper limits of normal criteria for pregnant patients and a high index of suspicion is required for diagnosis. Imaging is also limited due to high risk of radiation exposure with computed tomography and teratogenicity with contrast agents. The optimal treatment strategy is surgical resection of adrenal adenoma or pituitary adenoma, ideally before 24 weeks of gestation to reduce the risk of maternal and fetal complications. In mild cases, surgery can be postponed until after delivery and treatment should focus on controlling metabolic complications of hypercortisolism, such as hypertension and dysglycemia. Maternal and fetal outcomes of excess cortisol exposure, except fetal loss, are not readily improved by successful treatment of hypercortisolism.

New Insights into the Role of Insulin and Hypothalamic-Pituitary-Adrenal (HPA) Axis in the Metabolic Syndrome

Recent data suggests that (pre)diabetes onset is preceded by a period of hyperinsulinemia. Consumption of the "modern" Western diet, over-nutrition, genetic background, decreased hepatic insulin clearance, and fetal/metabolic programming may increase insulin secretion, thereby causing chronic hyperinsulinemia. Hyperinsulinemia is an important etiological factor in the development of metabolic syndrome, type 2 diabetes, cardiovascular disease, polycystic ovarian syndrome, and Alzheimer's disease. Recent data suggests that the onset of prediabetes and diabetes are preceded by a variable period of hyperinsulinemia. Emerging data suggest that chromic hyperinsulinemia is also a driving force for increased activation of the hypothalamic-adrenal-pituitary (HPA) axis in subjects with the metabolic syndrome, leading to a state of "functional hypercortisolism". This "functional hypercortisolism" by antagonizing insulin actions may prevent hypoglycemia. It also disturbs energy balance by shifting energy fluxes away from muscles toward abdominal fat stores. Synergistic effects of hyperinsulinemia and "functional hypercortisolism" promote abdominal visceral obesity and insulin resistance which are core pathophysiological components of the metabolic syndrome. It is hypothesized that hyperinsulinemia-induced increased activation of the HPA axis plays an important etiological role in the development of the metabolic syndrome and its consequences. Numerous studies have demonstrated reversibility of hyperinsulinemia with lifestyle, surgical, and pharmaceutical-based therapies. Longitudinal studies should be performed to investigate whether strategies that reduce hyperinsulinemia at an early stage are successfully in preventing increased activation of the HPA axis and the metabolic syndrome.

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.

Pathophysiological Link between Insulin Resistance and Adrenal Incidentalomas

Adrenal incidentalomas are incidentally discovered adrenal masses greater than one centimeter in diameter. An association between insulin resistance and adrenal incidentalomas has been established. However, the pathophysiological link between these two conditions remains incompletely characterized. This review examines the literature on the interrelationship between insulin resistance and adrenal masses, their subtypes, and related pathophysiology. Some studies show that functional and non-functional adrenal masses elicit systemic insulin resistance, whereas others conclude the inverse. Insulin resistance, hyperinsulinemia, and the anabolic effects on adrenal gland tissue, which have insulin and insulin-like growth factor-1 receptors, offer possible pathophysiological links. Conversely, autonomous adrenal cortisol secretion generates visceral fat accumulation and insulin resistance. Further investigation into the mechanisms and timing of these two pathologies as they relate to one another is needed and could be valuable in the prevention, detection, and treatment of both conditions.

Vitamin D deficiency and tumor aggressiveness in gastroenteropancreatic neuroendocrine tumors

PURPOSE

Data regarding vitamin D status in patients affected by gastroenteropancreatic (GEP) neuroendocrine tumor (NET) are limited and often showing contrasting results. The aim of the study was to evaluate the incidence of vitamin D deficiency (<20 ng/mL) in GEP-NET patients and compare the 25-hydroxyvitamin D (25(OH)D) levels with clinicopathological parameters and clinical outcome.

METHODS

A retrospective cross-sectional study including 75 low grade (G1-G2) GEP-NETs and 123 healthy controls matched for age, sex, and body mass index, was performed.

RESULTS

GEP-NET patients had significantly lower 25(OH)D levels compared to controls (17.9 ± 7.8 vs 24.2 ± 7.7 ng/mL, p < 0.0001). Ileal NETs were associated to lower 25(OH)D levels compared to other primary tumor sites (p = 0.049) and small bowel resection posed a significant increased risk of severe vitamin D deficiency (OR = 2.81, 95% CI = 1.25-3.37, p = 0.018). No correlation with somatostatin analogs treatment was found. 25(OH)D levels were significantly lower in G2 compared to G1 GEP-NETs (15.6 ± 7.8 vs 19.9 ± 7.4 ng/mL, p = 0.016) and in patients with progressive disease (12.6 ± 5.7 ng/mL) compared to those with stable disease (mean 21.5 ± 8.2 ng/mL, p = 0.001) or tumor free after surgery (19.6 ± 7.3 ng/mL, p = 0.002). Patients with vitamin D deficiency and insufficiency had shorter progression-free survival compared to those with sufficiency (p = 0.014), whereas no correlation was found with disease-specific survival.

CONCLUSIONS

Vitamin D deficiency is highly prevalent among GEP-NETs and could be associated with high tumor grade and disease progression. Therefore, the monitoring of 25(OH)D levels is relevant in these patients and vitamin D supplementation should be considered in the management of GEP-NET patients with vitamin D deficiency or insufficiency.

Mitotane treatment in adrenocortical carcinoma: mechanisms of action and predictive markers of response to therapy

INTRODUCTION

Adrenocortical carcinoma (ACC) is a rare malignancy with a high risk of recurrence even in cases with complete surgical tumor resection. Mitotane represents the cornerstone of the adjuvant therapy as well as the first line of medical treatment in advanced cases. However, evidence on mitotane efficacy is mostly based on retrospective studies and the use of mitotane continues to represent a clinical challenge.

EVIDENCE ACQUISITION

Mitotane causes selective damage to adrenocortical cells, causing an increase of cell apoptosis through a disruption of mitochondria and the induction of the endoplasmic reticulum stress. Different clinical and molecular markers predicting response to mitotane have been proposed with uncertain results. Attainment of mitotane plasma levels within the target range of 14 to 20 mg/L represent the strongest predictor of mitotane effectiveness both in adjuvant and advanced tumor setting. The occurrence of late recurrence after primary ACC diagnosis and changes in metabolic activity on FDG-PET are only weakly associated with mitotane response. Among the proposed molecular markers associated with mitotane efficacy, the investigation of the CYP2W1*6 and CYP2B6*6 single nucleotide polymorphisms appears to be currently the most promising predictive molecular markers of mitotane therapy. However, none of the evaluated markers has been validated for clinical use.

CONCLUSIONS

In the era of precision medicine, a better insight into mitotane molecular mechanisms as well as the potential use in the daily clinical practice of clinical parameters and molecular markers predicting the individual response to mitotane are urgently needed.

Nonfunctional adrenal adenomas and impaired glucose metabolism: a systematic review and meta-analysis

PURPOSE

Evidence on nonfunctioning adrenal incidentaloma's (NFAI) associated comorbidities and in particular, glucose disorders, is unclear in contrast to adrenal tumors with mild autonomous cortisol secretion. The current systematic review and meta-analysis aimed to assess the burden of impaired glucose metabolism including diabetes mellitus type 2 (T2DM), fasting blood glucose (FBG), and fasting blood insulin (FBI) levels in patients with NFAI and 1-mg overnight dexamethasone suppression test (ODST) ≤ 1.8 μg/dl across published studies.

METHODS

We searched PubMed, Cochrane, and Scopus databases for identifying studies published between 1956 and March 2021. Twenty-five studies met the selection criteria including prospective, retrospective, and case-control studies. Two reviewers independently extracted studies, participants' characteristics and outcome data in a total pooled sample of 1548 patients.

RESULTS

Patients with NFAI had twofold [(odds ratio (OR) (95% confidence interval (CI)): 2.03 (1.39-2.98)] increased odds to present T2DM as well as higher FBG [weighted mean difference (WMD) (95% CI): 3.85 (1.96-5.74)] and homeostasis model assessment (HOMA) [WMD (95% CI): 0.68 (0.23-1.12)] with respect to controls. On the contrary, the WMD of FBI levels did not differ between the two groups. The incidence of T2DM in a subgroup analysis of patients with NFAI without glucose disorders at baseline was 6% [pooled incidence (95% CI): 0.06 (0.04-0.09)].

CONCLUSIONS

Patients with NFAI and 1-mg ODST ≤ 1.8 μg/dl presented higher odds of T2DM and higher levels of FBG and HOMA index than healthy controls.

Insulin-like growth factor 2 (IGF2) expression in adrenocortical disease due to PRKAR1A mutations compared to other benign adrenal tumors

PURPOSE

Insulin-like growth factor-II (IGF2), a key regulator of cell growth and development, is tightly regulated in its expression by epigenetic control that maintains its monoallelic expression in most tissues. Biallelic expression of IGF2 resulting from loss of imprinting (LOI) has been reported in adrenocortical tumors. In this study, we wanted to check whether adrenocortical lesions due to PRKAR1A mutations lead to increased IGF2 expression from LOI and compare these findings to those in other benign adrenal lesions.

METHODS

We compared the expression of IGF2 by RNA and protein studies in primary pigmented nodular adrenocortical disease (PPNAD) caused by PRKAR1A gene mutations to that in primary macronodular adrenocortical hyperplasia (PMAH) and cortisol-producing adenomas (CPA) that did not have any mutations in known genes. We also checked LOI in all lesions by DNA allelic studies and the expression of other components of IGF2 signaling at the RNA and protein level.

RESULTS

We identified cell clusters overexpressing IGF2 in PPNAD; although immunostaining was patchy, overall, by RNA and immunoblotting PPNAD expressed high IGF2 message and protein. However, this was not due to LOI, as there was no correlation between IGF2 expression and the presence of LOI.

CONCLUSIONS

Our data pointed to over-expression of IGF2 protein in PPNAD compared to other benign adrenocortical lesions, such as PMAH and CPA. However, there was no correlation of IGF2 mRNA levels with LOI of IGF2/H19. The discrepancy between mRNA and protein levels with regards to LOI points, perhaps, to different control of IGF2 gene expression in PPNAD.

The trans-ancestral genomic architecture of glycemic traits

Glycemic traits are used to diagnose and monitor type 2 diabetes and cardiometabolic health. To date, most genetic studies of glycemic traits have focused on individuals of European ancestry. Here we aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P < 5 × 10-8), 80% of which had no significant evidence of between-ancestry heterogeneity. Analyses restricted to individuals of European ancestry with equivalent sample size would have led to 24 fewer new loci. Compared with single-ancestry analyses, equivalent-sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic-feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase our understanding of diabetes pathophysiology by using trans-ancestry studies for improved power and resolution.

The Role of Biomarkers in Adrenocortical Carcinoma: A Review of Current Evidence and Future Perspectives

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy arising from the adrenal cortex often with unexpected biological behavior. It can occur at any age, with two peaks of incidence: in the first and between fifth and seventh decades of life. Although ACC are mostly hormonally active, precursors and metabolites, rather than end products of steroidogenesis are produced by dedifferentiated and immature malignant cells. Distinguishing the etiology of adrenal mass, between benign adenomas, which are quite frequent in general population, and malignant carcinomas with dismal prognosis is often unfeasible. Even after pathohistological analysis, diagnosis of adrenocortical carcinomas is not always straightforward and represents a great challenge for experienced and multidisciplinary expert teams. No single imaging method, hormonal work-up or immunohistochemical labelling can definitively prove the diagnosis of ACC. Over several decades' great efforts have been made in finding novel reliable and available diagnostic and prognostic factors including steroid metabolome profiling or target gene identification. Despite these achievements, the 5-year mortality rate still accounts for approximately 75% to 90%, ACC is frequently diagnosed in advanced stages and therapeutic options are unfortunately limited. Therefore, imperative is to identify new biological markers that can predict patient prognosis and provide new therapeutic options.

Is there a role for the IGF system and epidermal growth factor (EGF) in the pathogenesis of adrenocortical adenomas? A preliminary case-control study

Adrenal incidentalomas (AI) are very common and mostly they are non-functioning adenomas (NFA). NFAs are often associated with insulin resistance and metabolic syndrome. Several biomarkers, including certain growth factors, may participatein the pathogenesis ofmetabolic changes in patients with adrenal adenomas.Patients with NFA and age-matched control subjects were enrolled in the study. Data on age, gender, presence of metabolic syndrome or its components were obtained for each subject. Blood samples were obtained and glycemia, insulinemia, lipid profile, and selected growth factor levels were measured. Forty-three patients with NFA and 40 controls were included in the study. Differences were not found in the metabolic syndrome and its components prevalence or in the biochemical profile between patients and the control group. Significant differences were noticed in the levels of IGF1, IGF2, and IGFBP3 (p=0.016, p=0.005, p=0.004, respectively), but there were no differences in VEGF or EGF concentrations. In NFA patients, an association between glycemia and EGF levels was present (p=0.026). No significant correlations between tumor size and insulin or growth factor concentrations were present in AI patients. Significantly higher serum IGF1, IGF2, and IGFBP3 concentrations in NFA patients may support the role of the IGF axis in the pathogenesis of adrenocortical lesions.No correlation between IGFs or IGFBP3 and parameters of glucose or lipid metabolism was found. Present results may support the role of the growth hormone axis rather than hyperinsulinemia and insulin resistance in the pathogenesis of adrenocortical adenomas.

Epidemiology of pancreatic neuroendocrine neoplasms: a gender perspective

PURPOSE

Pancreatic neuroendocrine neoplasms (PNENs) are a group of clinically rare and heterogeneous tumors of the pancreas. Currently there are no studies investigating the gender difference in PNEN susceptibility. Thus, the purpose of this study was aimed at examining how gender shapes risk factors, clinicopathological features, and comorbidities in PNENs.

METHODS

The study design consisted of an Italian multicenter, retrospective study. The study included all consecutive patients with PNENs followed at the participating centers. Two hundred and twenty-nine patients (105 males,124 females, age 54 ± 0.98 years) with PNENs were enrolled at the participating centers. The clinicopathological features (age, gender, BMI, histology, tumor size, tumor grade, distant metastasis, hormonal function, and diagnostic circumstances), comorbidities (cardiovascular diseases (CVD), pancreatitis, type 2 diabetes (T2DM), and potential risk factors (smoking and drinking) were included in the analysis.

RESULTS

Females were slightly prevalent (54.15%). PNENs were diagnosed at younger age in females compared to males (p = 0.04). The prevalence of CVD was significantly higher in males than in females (p = 0.006). In the female group, the presence of T2DM was significantly associated with higher tumor grade (p = 0.04) and metastatic disease (p = 0.02). The proportion of smokers and alcohol drinkers was significantly higher in the male group (p < 0.001). No significant gender differences were detected regarding the other parameters included in the analysis.

CONCLUSIONS

This study has identified gender differences of PNENs in terms of age at diagnosis, associated comorbidities, and potential risk factors. A gender-tailored approach could become a potential strategy to better understand the natural history of PNENs and improve the effectiveness of PNENs clinical management.

Glucose metabolism disorders in patients with adrenal gland disorders: pathophysiology and management

The aim of this review is to explore and discuss disorders of glucose metabolism that can arise in individuals with adrenal gland disorders, as well as to enumerate the available therapeutic treatments for these while considering their benefits and drawbacks. Hyperfunctioning adrenal glands, as in hypercortisolism, hyperaldosteronism, and malignancy, or hypofunctioning of adrenal glands, as in adrenal insufficiency, can lead to carbohydrate metabolism dysregulation with subsequent glucometabolic repercussions, either hyperglycemia or hypoglycemia. Glycemic disorders further affect patients' quality of life and represent a therapeutic dilemma for physicians. Current management strategies for glycemic dysregulation in individuals with adrenal gland disorders are fighting the underlying causes, as well as utilizing antidiabetic therapies that aid in maintaining euglycemia. Further research focused on discovering drug preparations of greater accuracy and effectiveness tailored to patients with adrenal problems as well as studies investigating optimal lifestyle management models for these individuals will assist towards achieving optimal regulation of glucose metabolism.

Next-generation therapies for adrenocortical carcinoma

Almost one decade ago, etoposide, doxorubicin, cisplatin and mitotane (EDP-M) has been established as first-line systemic therapy of metastatic adrenocortical carcinoma (ACC). Although heterogeneous, the prognosis of advanced stage ACC is still poor and novel treatments are urgently needed. This article provides a short summary of current systemic ACC treatment and provides a comprehensive overview of new therapeutic approaches that have been investigated in the past years, including drugs targeting the IGF pathway, tyrosine kinase inhibitors, radionuclide treatment, and immunotherapy. The results of most of these trials were disappointing and we will discuss possible reasons why these drugs failed (e.g. drug interactions with mitotane, disease heterogeneity with exceptional responses in very few patients, and resistance mechanisms to immunotherapy). We then will present potential new drug targets that have emerged from many molecular studies (e.g. wnt/β-catenin, cyclin-dependent kinases, PARP1) that may be the foundation of next-generation therapies of ACC.

Exacerbation of Cushing's syndrome during pregnancy: stimulation of a cortisol-secreting adrenocortical adenoma by ACTH originating from the foeto-placental unit

A 29-year-old G4A3 woman presented at 25 weeks of pregnancy with progressive signs of Cushing's syndrome (CS), gestational diabetes requiring insulin and hypertension. A 3.4 × 3.3 cm right adrenal adenoma was identified during abdominal ultrasound imaging for nephrolithiasis. Investigation revealed elevated levels of plasma cortisol, 24 h urinary free cortisol (UFC) and late-night salivary cortisol (LNSC). Serum ACTH levels were not fully suppressed (4 and 5 pmol/L (N: 2-11)). One month post-partum, CS regressed, 24-h UFC had normalised while ACTH levels were now less than 2 pmol/L; however, dexamethasone failed to suppress cortisol levels. Tests performed in vivo 6 weeks post-partum to identify aberrant hormone receptors showed no cortisol stimulation by various tests (including 300 IU hLH i.v.) except after administration of 250 µg i.v. Cosyntropin 1-24. Right adrenalectomy demonstrated an adrenocortical adenoma and atrophy of adjacent cortex. Quantitative RT-PCR analysis of the adenoma revealed the presence of ACTH (MC2) receptor mRNA, while LHCG receptor mRNA was almost undetectable. This case reveals that CS exacerbation in the context of pregnancy can result from the placental-derived ACTH stimulation of MC2 receptors on the adrenocortical adenoma. Possible contribution of other placental-derived factors such as oestrogens, CRH or CRH-like peptides cannot be ruled out. Learning points: Diagnosis of Cushing's syndrome during pregnancy is complicated by several physiological alterations in hypothalamic-pituitary-adrenal axis regulation occurring in normal pregnancy. Cushing's syndrome (CS) exacerbation during pregnancy can be associated with aberrant expression of LHCG receptor on primary adrenocortical tumour or hyperplasia in some cases, but not in this patient. Placental-derived ACTH, which is not subject to glucocorticoid negative feedback, stimulated cortisol secretion from this adrenal adenoma causing transient CS exacerbation during pregnancy. Following delivery and tumour removal, suppression of HPA axis can require several months to recover and requires glucocorticoid replacement therapy.

Insulin resistance and adrenal incidentalomas: A bidirectional relationship

An adrenal incidentaloma (AI) is an adrenal mass incidentally found via a radiological modality, independent of an endocrinological investigation. In this review, we aimed to investigate the possible reasons behind the increased frequency in AI detection, especially in ageing populations. The pathophysiological effects of insulin resistance (IR), hyperinsulinemia and various anabolic pathways are analyzed. In addition, we review data from studies indicating an increased incidence of adrenal adenomas and carcinomas in patients with type 2 diabetes mellitus (T2DM). The establishment of obesity as a global epidemic, with a higher prevalence in the female than in the male population, coincide with data regarding AIs and the conditions may share a pathophysiological basis. Furthermore, we discuss the bidirectional association of AIs with obesity, insulin resistance and T2DM, especially in patients with autonomous cortisol secretion. Lastly, as per the definition of an AI, we touch upon the evolution of radiological imaging as another possible cause of the rise in prevalence of AIs, especially concerning the greater use and precision of computed tomography (CT).

The role of insulin-like growth factor system in the adrenocortical tumors

INTRODUCTION

The different presentation of adrenocortical tumors in benign adenoma (ACA) or adrenocortical carcinoma (ACC) is related to the variability at the molecular level. The insulin-like growth factor (IGF) system is one of the most frequently altered pathways in ACC. In this review we will critically analyze the evidence regarding the pathogenic role of the IGF system in adrenal tumorigenesis, focusing on ACC. We will also examine the preclinical and clinical studies which investigated the targeting of the IGF system as a therapeutic approach in ACC.

EVIDENCE ACQUISITION

The IGF system plays a crucial role in the embryogenesis of adrenal glands. No significant alterations of the IGF system were observed in ACA. In ACC, the IGF2 overexpression is one of the most frequent molecular change presented in more than 85% of cases. However, IGF2 seems to be only a tumor progression factor which requires additional hits to trigger adrenal tumorigenesis. Also, the IGF1 receptor (IGF1R) appears to be higher expressed in ACC. Many IGF1R target-drugs have been developed to inhibit the activation of the IGF system.

EVIDENCE SYNTHESIS

Preclinical studies using antibody or tyrosine kinase which target the IGF1R, or the dual-targeting of IGF1R and insulin receptor (IR) reduced ACC cells proliferation both in vitro and in vivo in mouse xenograft model. However, these promising results were not confirmed in clinical trials.

CONCLUSIONS

Nowadays, predictive markers for the response of target-IGF therapy are missing and further studies which investigate new molecular markers and evaluate the entire IGF receptors, including the IR, are urgently needed.

Multiplatform plasma fingerprinting in cancer cachexia: a pilot observational and translational study

BACKGROUND

Cachexia is a metabolic syndrome that affects up to 50-80% of cancer patients. The pathophysiology is characterized by a variable combination of reduced food intake and abnormal metabolism, including systemic inflammation and negative protein and energy balance. Despite its high clinical significance, defined diagnostic criteria and established therapeutic strategies are lacking. The 'omics' technologies provide a global view of biological systems. We hypothesize that blood-based metabolomics might identify findings in cachectic patients that could provide clues to gain knowledge on its pathophysiology, and eventually postulate new therapeutic strategies.

METHODS

This is a cross-sectional observational study in two cohorts of cancer patients, with and without cachexia. Patients were consecutively recruited from routine clinical practice of a General Oncology Department at '12 de Octubre' University Hospital. Selected clinical and biochemical features were collected. Blood metabolite fingerprinting was performed using three analytical platforms, gas chromatography coupled to mass spectrometry (GC-MS), capillary electrophoresis coupled to mass spectrometry (CE-MS), and liquid chromatography coupled to mass spectrometry (LC-MS). Besides, we performed pathway-based metabolite analyses to obtain more information on biological functions.

RESULTS

A total of 15 subjects were included in this study, 8 cachectic and 7 non-cachectic patients. Metabolomic analyses were able to correctly classify their samples in 80% (GC-MS), 97% (CE-MS), 96% [LC-MS (positive mode)], and 89% [LC-MS (negative mode)] of the cases. The most prominent metabolic alteration in plasma of cachectic patients was the decrease of amino acids and derivatives [especially arginine, tryptophan, indolelactic acid, and threonine, with 0.4-fold change (FC) compared with non-cachectic patients], along with the reduction of glycerophospholipids [mainly lysophosphatidylcholines(O-16:0) and lysophosphatidylcholines(20:3) sn-1, FC = 0.1] and sphingolipids [SM(d30:0), FC = 0.5]. The metabolite with the highest increase was cortisol (FC = 1.6). Such alterations suggest a role of the following metabolic pathways in the pathophysiology of cancer cachexia: arginine and proline metabolism; alanine, aspartate, and glutamate metabolism; phenylalanine metabolism; lysine degradation; aminoacyl-tRNA biosynthesis; fatty acid elongation in mitochondria; tricarboxylic acids cycle; among others.

CONCLUSIONS

These findings suggest that plasma amino acids and lipids profiling has great potential to find the mechanisms involved in the pathogenesis of cachexia. Metabolic profiling of plasma from cancer patients show differences between cachexia and non-cachexia in amino acids and lipids that might be related to mechanisms involved in its pathophysiology. A better understanding of these mechanisms might identify novel therapeutic approaches to palliate this unmet medical condition.

Luteinizing hormone and insulin resistance in menopausal patients with adrenal incidentalomas: The cause-effect relationship?

OBJECTIVE

A high prevalence of insulin resistance (IR) has proven to manifest in patients with adrenal incidentalomas (AI). It has been demonstrated that an increase in IR is related to the size of tumourous masses; additionally, luteinizing hormone (LH)-dependent adrenal pathologies are well documented in patients with LH-responsive adrenal tumours occurring under conditions of physiologically elevated LH. We hypothesized that an association between LH and insulin might play a role in adrenal tumourigenesis and steroidogenesis.

DESIGN

The aim of our study was to investigate the association between LH and IR; adrenal tumour size (ATS) and IR; LH and cortisol after the 1 mg overnight dexamethasone test (1 mg DST); and ATS and 1 mg DST cortisol in AI patients. This was a case-control study conducted in the Clinic for Endocrinology, Diabetes and Metabolic Diseases in Belgrade, Serbia. The total study group consisted of 105 menopausal women: 75 AI patients [27 with nonfunctional AI (NAI) and 48 with (possible) autonomous cortisol secretion ((P)ACS)] and 30 age-, BMI-, LH- and menopause duration-matched healthy control (HC) women. To estimate IR, we used homeostasis model assessment (HOMA-IR).

RESULTS

Luteinizing hormone and ATS are in a significant positive correlation with HOMA-IR and 1 mg DST cortisol in menopausal patients with AI and (P)ACS.

CONCLUSIONS

Our data point to a possible cause-effect relationship between LH and insulin in patients with AI and (P)ACS adding to the body of evidence of their involvement in adrenal tumourigenesis and steroidogenesis.

The Role of Insulin Resistance/Hyperinsulinism on the Rising Trend of Thyroid and Adrenal Nodular Disease in the Current Environment

Thyroid follicular cells, as well as adrenocortical cells, are endowed by an intrinsic heterogeneity regarding their growth potential, in response to various stimuli. This heterogeneity appears to constitute the underlying cause for the focal cell hyperplasia and eventually the formation of thyroid and adrenal nodules, under the influence of growth stimulatory factors. Among the main stimulatory factors are the pituitary tropic hormones, thyroid-stimulating hormone (TSH) or thyrotropin and adrenocorticotropic hormone (ACTH), which regulate the growth and function of their respective target cells, and the insulin/insulin-like growth factor system, that, through its mitogenic effects, can stimulate the proliferation of these cells. The predominance of one or the other of these growth stimulatory factors appears to determine the natural history of thyroid and adrenal nodular disease. Thus, iodine deficiency was, in the past, the main pathogenic factor responsible, through a transient rise in TSH secretion, for the endemic nodular goiter with the characteristic colloid thyroid nodules among the inhabitants in iodine deficient areas. The correction of iodine deficiency was followed by the elimination of endemic colloid goiter and the emergence of thyroid autoimmunity. The recent epidemic of obesity and metabolic syndrome (MS), or insulin resistance syndrome, has been associated with the re-emergence of nodular thyroid disease. A parallel rise in the incidence of benign, nonfunctional adrenocortical tumors, known as adrenal incidentalomas, has also been reported in association with the manifestations of the MS. It is likely that the compensatory to insulin resistance hyperinsulinemia may be responsible for the rising trend of thyroid and adrenal nodular disease in the current environment.