Urinary steroid profile in adrenocortical tumors

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.

Delineating endogenous Cushing's syndrome by GC-MS urinary steroid metabotyping

BACKGROUND

Diagnosing Cushing's syndrome (CS) is highly complex. As the diagnostic potential of urinary steroid metabolome analysis by gas chromatography-mass spectrometry (GC-MS) in combination with systems biology has not yet been fully exploited, we studied a large cohort of patients with CS.

METHODS

We quantified daily urinary excretion rates of 36 steroid hormone metabolites. Applying cluster analysis, we investigated a control group and 168 patients: 44 with Cushing's disease (CD) (70% female), 18 with unilateral cortisol-producing adrenal adenoma (83% female), 13 with primary bilateral macronodular adrenal hyperplasia (PBMAH) (77% female), and 93 ruled-out CS (73% female).

FINDINGS

Cluster-Analysis delineated five urinary steroid metabotypes in CS. Metabotypes 1, 2 and 3 revealing average levels of cortisol and adrenal androgen metabolites included patients with exclusion of CS or and healthy controls. Metabotype 4 reflecting moderately elevated cortisol metabolites but decreased DHEA metabolites characterized the patients with unilateral adrenal CS and PBMAH. Metabotype 5 showing strong increases both in cortisol and DHEA metabolites, as well as overloaded enzymes of cortisol inactivation, was characteristic of CD patients. 11-oxygenated androgens were elevated in all patients with CS. The biomarkers THS, F, THF/THE, and (An + Et)/(11β-OH-An + 11β-OH-Et) correctly classified 97% of patients with CS and 95% of those without CS. An inverse relationship between 11-deoxygenated and 11-oxygenated androgens was typical for the ACTH independent (adrenal) forms of CS with an accuracy of 95%.

INTERPRETATION

GC-MS based urinary steroid metabotyping allows excellent identification of patients with endogenous CS and differentiation of its subtypes.

FUNDING

The study was funded by the Else Kröner-Fresenius-Stiftung and the Eva-Luise-und-Horst-Köhler-Stiftung.

Characterisation of the urinary steroid profile of patients with nonfunctioning adrenal incidentalomas: A matched controlled cross-sectional study

AIM

To identify alterations in steroid metabolism in patients with nonfunctioning adrenal incidentalomas (NFAIs) through the analysis of their urinary steroid profile (USP).

METHODS

Cross-sectional study with one study group (NFAIs, cortisol post dexamethasone suppression test [DST] ≤ 1.8 µg/dl [49.7 nmol/L]) and 2 control groups: patients with autonomous cortisol secretion (ACS group, cortisol post-DST > 1.8 µg/dl (49.7 nmol/L) and patients without adrenal tumours (healthy-adrenal group). Twenty-four-hour urine collections for USP measurement (total and free fraction of 51 24 h-urine specimens) were obtained from 73 participants (24 with NFAIs, 24 without AIs, and 25 with ACS). USP was determined by gas chromatography coupled to mass spectrometry. Patients of the three groups were matched according to sex, age (±5 years-old) and body mass index (±5 kg/m² ).

RESULTS

Compared to healthy-adrenal controls, patients with NFAIs had a lower excretion of androgen metabolites (230.5 ± 190.12 vs. 388.7 ± 328.58 µg/24 h, p = .046) and a higher excretion of urinary free cortisol (UFC) (54.3 ± 66.07 vs. 25.4 ± 11.16 µg/24 h, p = .038). UFC was above the reference range in 20.8% of patients in the NFAI, compared to 0% in the healthy-adrenal group (p = .018). Patients with ACS had a higher prevalence of hypertension, dyslipidemia, and diabetes than patients with NFAIs or the control group. A lower excretion of androgen metabolites (218.4 ± 204.24 vs. 231 ± 190 µg/24 h, p = .041) and a nonsignificant higher excretion of glucocorticoid metabolites (2129.6 ± 1195.96 vs. 1550.8 ± 810.03 µg/24 h, p = .180) was found in patients with ACS compared to patients with NFAIs.

CONCLUSION

NFAIs seem to secrete a subtle, yet clinically relevant, excess of glucocorticoids. Future studies are needed to confirm our findings; and to identify metabolic alterations associated with an increased cardiometabolic risk.

Cardiometabolic profile and urinary metabolomic alterations in non-functioning adrenal incidentalomas: A review

BACKGROUND

The incidence of adrenal incidentalomas (AIs) has increased over the last 20 years, most of which are apparently non-functioning adrenal adenomas. However, increased evidence supports the existence of an association between non-functioning adrenal incidentalomas (NFAI) and an unfavourable cardio-metabolic profile.

METHODS

This study offers a comprehensive review of the available evidence supporting a higher cardiometabolic risk in NFAIs compared to controls without adrenal tumours. Moreover, it summarises the studies focused on the differential urinary metabolomic profile of NFAI and controls without adrenal lesions.

RESULTS

This adverse metabolic profile of patients with NFAI includes a higher prevalence of insulin resistance, obesity, hypertension, hyperglycaemia, dyslipidaemia, and cardiovascular alterations and mortality compared to healthy controls without adrenal tumours. Although the pathophysiology that explains the association between NFAI and the parameters of metabolic syndrome and cardiovascular risk is a relatively unexplored field of study, some evidence supports that there are a series of incipient alterations in cortisol metabolism not detected with the classical tests that led to this detrimental profile. These alterations may be potentially detected by a comprehensive metabolomics approach. Several studies detected a shift towards an increase of urinary cortisol metabolites excretion in NFAIs compared to controls without adrenal tumours.

CONCLUSION

In view of the higher cardiometabolic risk in NFAI than in controls without adrenal tumours, and the detected alterations in metabolomics profile of NFAI, I propose that the term of NFAI should be changed for another term that best fits to its linked cardiometabolic profile.

A dilute-and-shoot liquid chromatography-tandem mass spectrometry method for urinary 18-hydroxycortisol quantification and its application in establishing reference intervals

BACKGROUND

Eighteen-hydroxycortisol (18-OHF) is a potential biomarker for differential diagnosis of the two major primary aldosteronism subtypes, aldosterone-producing adenoma, and idiopathic hyperaldosteronism.

METHODS

Urine samples were processed, and the 18-OHF in urine samples were successfully quantified by in-house established dilute-and-shoot liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Separation was accomplished on a Sigma Ascentis Express C18 column with a gradient mixture of phase (A) 0.2% formic acid in water and phase (B) 0.2% formic acid in methanol at a flow rate of 0.4 ml/min. Mass spectrometric detection was performed in positive electrospray ionization mode via a mass spectrometer.

RESULTS

The linearity of urinary 18-OHF ranged from 4.28 to 8.77 × 103  nmol/L, with a lower limit of quantification at 4.28 nmol/L. The intra- and inter-precision were both below 3%. The range of analytical recovery was 97.8%-109.2%. The validated dilute-and-shoot LC-MS/MS method was compared with the SPE LC-MS/MS method modified from the one reported in 2013. The results by Passing-Bablok regression analysis and Bland-Altman plotting demonstrated a good agreement between the two methods. The presented method was then applied to establish sex-specific reference intervals from 62 males and 62 females, respectively. The calculated 2.5%-97.5% reference intervals for 24-h urinary 18-OHF were 113-703 nmol/day for males and 71.2-450 nmol/day for females.

CONCLUSION

The presented dilute-and-shoot LC-MS/MS method for 18-OHF quantification showed a good performance in the clinical application. Furthermore, the sex-specific reference intervals for 24-h urinary 18-OHF were first established and quite important for its application in primary aldosteronism subtyping.

A Proposal for Nomenclature Revision of Non-functioning Adrenal Incidentalomas as Adrenal Lesions of Undetermined Secretion of Adrenal Steroids (ALUSAS)

In this commentary we propose a change of the nomenclature of non-functioning adrenal incidentalomas (NFAI) to adrenal lesions of undetermined secretion of adrenal steroids (ALUSAS) since there are mounting evidence suggesting that a substantial proportion of so-called NFAIs do actually secrete steroids in excess. In fact, it is known that some NFAIs develop ACS over time. In the commentary we justify the change of term by summarizing the evidence that shows that NFAIs present a higher cardiometabolic risk than the general population, and the metabolomics studies in which an increase in cortisol metabolites is observed in patients with NFAI.

Plasma Steroid Profiling in Patients With Adrenal Incidentaloma

CONTEXT

Most patients with adrenal incidentaloma have nonfunctional lesions that do not require treatment, while others have functional or malignant tumors that require intervention. The plasma steroid metabolome may be useful to assess therapeutic need.

OBJECTIVE

This work aimed to establish the utility of plasma steroid profiling combined with metanephrines and adrenal tumor size for the differential diagnosis of patients with adrenal incidentaloma.

METHODS

This retrospective cross-sectional study, which took place at 7 European tertiary-care centers, comprised 577 patients with adrenal incidentaloma, including 19, 77, 65, 104 and 312 respective patients with adrenocortical carcinoma (ACC), pheochromocytoma (PHEO), primary aldosteronism (PA), autonomous cortisol secretion (ACS), and nonfunctional adrenal incidentaloma (NFAI). Mesaures of diagnostic performance were assessed (with [95% CIs]) for discriminating different subgroups of patients with adrenal incidentaloma.

RESULTS

Patients with ACC were characterized by elevated plasma concentrations of 11-deoxycortisol, 11-deoxycorticosterone, 17-hydroxyprogesterone, androstenedione, and dehydroepiandrosterone-sulfate, whereas patients with PA had elevations of aldosterone, 18-oxocortisol, and 18-hydroxycortisol. A selection of those 8 steroids, combined with 3 others (cortisol, corticosterone, and dehydroepiandrosterone) and plasma metanephrines, proved optimal for identifying patients with ACC, PA, and PHEO at respective sensitivities of 83.3% (66.1%-100%), 90.8% (83.7%-97.8%), and 94.8% (89.8%-99.8%); and specificities of 98.0% (96.9%-99.2%), 92.0% (89.6%-94.3%), and 98.6% (97.6%-99.6%). With the addition of tumor size, discrimination improved further, particularly for ACC (100% [100%-100%] sensitivity, 99.5% [98.9%-100%] specificity). In contrast, discrimination of ACS and NFAI remained suboptimal (70%-71% sensitivity, 89%-90% specificity).

CONCLUSION

Among patients with adrenal incidentaloma, the combination of plasma steroid metabolomics with routinely available plasma free metanephrines and data from imaging studies may facilitate the identification of almost all clinically relevant adrenal tumors.

Urine steroid profile as a new promising tool for the evaluation of adrenal tumors. Literature review

PURPOSE

To review the literature assessing the diagnostic performance of urinary steroid profiling (USP) by high-performance liquid chromatography (LC-MS) or gas chromatography (GC) coupled to mass spectrometry (MS) in the evaluation of adrenal lesions, both in terms of functionality and malignancy.

RESULTS

The evaluation of adrenal incidentalomas (AI) aims to rule out malignancy and hormone excess. Current diagnostic protocols have several limitations and include time consuming and relatively complicated multi-step processes in most cases. On the contrary, USP by LC-MS/MS or LC-GC/MS offer an easy, comprehensive and non-invasive assessment of adrenal steroid secretion. USP complements current workups used in the evaluation of AIs by improving our ability to identify malignancy and/or autonomous hormone secretion.

CONCLUSIONS

Urine steroid profiling by LC-MS/MS and GC-MS allows a thorough, non-invasive, assessment of adrenal steroidogenesis as a whole which complement the current evaluation of AIs, and holds a promising role in the diagnosis of autonomous cortisol secretion, primary aldosteronism, and adrenal malignancy.

Primary Cultures and Cell Lines for In Vitro Modeling of the Human Adrenal Cortex

The human adrenal cortex is a complex endocrine organ that produces mineralocorticoids, glucocorticoids and androgens. These steroids are produced in distinct cell types located within the glomerulosa, fasciculata and reticularis of the adrenal cortex. Abnormal adrenal steroidogenesis leads to a variety of diseases that can cause hypertension, metabolic syndrome, infertility and premature adrenarche. The adrenal cortex can also develop steroid-producing adenomas and rarely adrenocortical carcinomas. In vitro cell culture models provide important tools to study molecular and cellular mechanisms controlling both the physiologic and pathologic conditions of the adrenal cortex. In addition, the presence of multiple steroid-metabolizing enzymes within adrenal cells makes it a model for defining possible endocrine disruptors that might block these enzymes. The regulation and dysregulation of human adrenal steroid production and cell division/tumor growth can be studied using freshly isolated cells but this requires access to human adrenal glands, which are not available to most investigators. Immortalized human adrenocortical cell lines have proven to be of considerable value in studying the molecular and biochemical mechanisms controlling adrenal steroidogenesis and tumorigenesis. Current human adrenal cell lines include the original NCI-H295 and its substrains: H295A, H295R, HAC13, HAC15, HAC50 and H295RA as well as the recently established MUC-1, CU-ACC1 and CU-ACC2. The current review will discuss the use of primary cultures of fetal and adult adrenal cells as well as adrenocortical cell lines as in vitro models for the study of human adrenal physiology and pathophysiology.

Incomplete Pattern of Steroidogenic Protein Expression in Functioning Adrenocortical Carcinomas

Autonomous steroid secretion is a common feature of adrenocortical carcinomas (ACC), although not always clinically evident owing to inefficient steroidogenesis with increased release of steroid precursors. Our study aim was to analyze the expression profile of four key proteins involved in the steroidogenesis cascade, in different adrenocortical tumors. Expression of proteins involved in steroidogenesis, namely steroidogenic acute regulatory protein (StAR), 11β-hydroxylase (CYP11B1), aldosterone synthase (CYP11B2) and 17α-hydroxylase (CYP17A1), were analyzed by immunohistochemistry in ACC (n = 14), adenomas presenting with Cushing’s syndrome (ACAc) (n = 11) and clinically non-functioning adenomas (ACAn) (n = 15). A percentage of the stained area for each protein was analyzed using ImageJ software for computerized morphometric quantification. CYP11B1, StAR and CYP17A1 expression were significantly lower in ACC when compared to ACAc. In addition, ACC presented co-staining cells for CYP11B1 and CYP11B2. CYP11B1 was the steroidogenic enzyme with the most discriminative power to distinguish ACC from ACAc, with a sensitivity of 100%, specificity of 92%, and an expression higher than 4.44%, indicating the presence of a cortisol secreting adenoma. ACC depicts an incomplete pattern of steroidogenic protein expression, with decreased CYP11B1 and CYP17A1, which could explain the predominant secretion of steroid precursors.

Determination of the steroid profile in alternative matrices by liquid chromatography tandem mass spectrometry

The simultaneous determination of a broad panel of steroids provides more accurate information about the hormonal status than the detection of a single hormone. For that reason, the determination of the steroid profile, i.e. the endogenous steroid hormones and their main metabolites, has become the most powerful tool for the study of hormonal imbalances. The usefulness of the evaluation of the steroid profile in urine and plasma is widely accepted. However, despite its broad potential applicability, the evaluation of the whole steroid profile in alternative matrices such as amniotic fluid, saliva and breast milk remains almost unexplored. In this research we developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of several steroids and their metabolites in amniotic fluid (28 analytes), saliva (15) and breast milk (12). Sample preparation, chromatographic conditions and mass spectrometric conditions (e.g. ionization species or ion source parameters) were optimized. The method was shown to be linear in the range of endogenous concentrations for all studied metabolites. Intra- and inter-assay accuracies were between 80% and 120% while intra- and inter-precisions were below 20% for all analytes in all matrices. The applicability of the method was evaluated by the comparison between the concentration ranges obtained in healthy volunteers (n = 30 per matrix) and the scarce data previously reported in literature. The concentration ranges for several analytes are reported for the first time. The present methodology represents a useful tool for the comprehensive evaluation of the steroid profile in alternative matrices and can be applicable for different clinical purposes.

Plasma Steroid Profiles in Subclinical Compared With Overt Adrenal Cushing Syndrome

CONTEXT

Diagnosis of subclinical adrenal hypercortisolism is based on several tests of the hypothalamic-pituitary-adrenal axis to establish mild alterations of cortisol secretion and dysregulated cortisol physiology.

OBJECTIVE

We assessed whether plasma steroid profiles might assist diagnosis of subclinical Cushing syndrome (SC).

DESIGN

Retrospective cross-sectional study.

SETTING

Two tertiary medical centers.

PATIENTS

Of 208 patients tested for hypercortisolism, disease was excluded in 152 and confirmed in 21 with overt adrenal Cushing syndrome (AC) compared to 35 with SC. Another 277 age- and sex-matched hypertensive and normotensive volunteers were included for reference.

MAIN OUTCOME MEASURES

A panel of 15 plasma steroids was measured by mass spectrometry, with classification by discriminant analysis.

RESULTS

Patients with SC had lower plasma concentrations of dehydroepiandrosterone and dehydroepiandrosterone-sulfate than subjects without SC (P < 0.05). The largest increases (P < 0.001) in plasma steroids among patients with SC were observed for 11-deoxycortisol and 11-deoxycorticosterone. Nevertheless, concentrations of 11-deoxycorticosterone, 11-deoxycortisol, and pregnenolone in patients with AC were higher (P < 0.05) than in those with SC. Patients with SC or AC could be distinguished from subjects without disease using this combination of steroids as precisely as with use of measurements of serum cortisol after administration of dexamethasone. The steroid combination provided superior diagnostic performance compared with each of the other routine biochemical tests.

CONCLUSION

Distinct plasma steroid profiles in patients with SC may provide a simple and reliable screening method for establishing the diagnosis.

Serum steroid profiling in Cushing's syndrome patients

CONTEXT

Cushing's syndrome is caused by increased exposure to cortisol. Discrimination of different causes of endogenous hypercortisolism can make a diagnostic dilemma.

PATIENTS AND METHODS

In serum samples from patients with Cushing's syndrome (47 with Cushing's disease, 6 with ectopic ACTH-dependent Cushing's syndrome, 16 with adrenal adenoma, 7 bilateral adrenal hyperplasia (BMAH) with overt Cushing's syndrome, 42 controls from the general population) using novel method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) we measured 94 serum steroids to search for steroid fingerprint of each subtype.

RESULTS

Patients with Cushing's disease and ectopic ACTH producing tumors showed elevated levels of androgens and their metabolites when compared with healthy controls. Mineralocorticoid precursors were also elevated in ectopic ACTH syndrome. The levels of androgens were decreased in adrenal adenomas and BMAH. ROC analysis showed 100% sensitivity and 93.6% specificity for 11β-hydroxyepiandrosterone sulfate for discrimination of Cushing's disease from ectopic ACTH secretion. We didn't find any significant (p < 0.05) difference in steroids that would discriminate BMAH from unilateral adenomas causing Cushing's syndrome.

CONCLUSION

Various causes of Cushing's syndrome show particular steroid fingerprints that can be used to discriminate and may help to achieve appropriate clinical diagnosis.

Steroid biomarkers in human adrenal disease

Adrenal steroidogenesis is a robust process, involving a series of enzymatic reactions that facilitate conversion of cholesterol into biologically active steroid hormones under the stimulation of angiotensin II, adrenocorticotropic hormone and other regulators. The biosynthesis of mineralocorticoids, glucocorticoids, and adrenal-derived androgens occur in separate adrenocortical zones as a result of the segregated expression of steroidogenic enzymes and cofactors. This mini review provides the principles of adrenal steroidogenesis, including the classic and under-appreciated 11-oxygenated androgen pathways. Several adrenal diseases result from dysregulated adrenal steroid synthesis. Herein, we review growing evidence that adrenal diseases exhibit characteristic modifications from normal adrenal steroid pathways that provide opportunities for the discovery of biomarker steroids that would improve diagnosis and monitoring of adrenal disorders.

Plasma Steroid Metabolome Profiling for Diagnosis and Subtyping Patients with Cushing Syndrome

BACKGROUND

Diagnosis of Cushing syndrome requires a multistep process that includes verification of hypercortisolism followed by identification of the cause of adrenocortical hyperfunction. This study assessed whether pituitary, ectopic, and adrenal subtypes of Cushing syndrome were characterized by distinct plasma steroid profiles that might assist diagnosis.

METHODS

In this retrospective cross-sectional study, mass spectrometric measurements of a panel of 15 plasma steroids were applied to 222 patient samples tested for Cushing syndrome. Disease was excluded in 138 and confirmed in 51 patients with pituitary Cushing syndrome, 12 with ectopic adrenocorticotropin secretion, and 21 with adrenal disease. Another 277 age- and sex-matched hypertensive and normotensive volunteers were included for comparison.

RESULTS

Compared with patients without disease, the largest increases in plasma steroids among patients with Cushing syndrome were observed for 11-deoxycortisol (289%), 21-deoxycortisol (150%), 11-deoxycorticosterone (133%), corticosterone (124%), and cortisol (122%). Patients with ectopic disease showed the most prominent increases, but there was considerable variation for other steroids according to subtype. Patients with adrenal disease had the lowest concentrations of androgens, whereas those with ectopic and pituitary disease showed the lowest concentrations of aldosterone. Plasma 18-oxocortisol was particularly low in ectopic disease. With the use of 10 selected steroids, subjects with and without different Cushing syndrome subtypes could be discriminated nearly as closely as with the use of salivary and urinary free cortisol, dexamethasone-suppressed cortisol, and plasma adrenocorticotropin (9.5% vs 5.8% misclassification).

CONCLUSIONS

Patients with different subtypes of Cushing syndrome show distinctive plasma steroid profiles that may offer a supplementary single-test alternative for screening purposes.

Adrenocortical adenomas with regression and myelolipomatous changes: urinary steroid profiling supports a distinctive benign neoplasm

BACKGROUND

Adrenocortical neoplasms are classically divided into adenomas (ACA) and carcinomas (ACC). Heterogeneous appearance and greater size are criteria to suggest malignancy, along with the urinary steroid profile (USP). The presence of regression and myelolipomatous changes in adenomas (ACA-RML) can contribute to confusion with ACC and its USP remains unknown.

OBJECTIVE

To evaluate the features of ACA-RML in comparison with other adrenocortical neoplasms.

METHODS

We selected consecutive ACA (11), ACA-RML (7) and ACC (13) cases for which USP analysis was performed before surgery and tissue was available for histological evaluation (King's College Hospital, 2005-2012). Cases were classified according to WHO and Armed Forces Institute of Pathology criteria. USPs were obtained by gas chromatography/mass spectrometry. Total excretion of individual steroids and indices (sums and ratios chosen to reflect steroid metabolic activity) were compared between ACA-RML, ACA and ACC.

RESULTS

In comparison with ACA, tumours in ACA-RML were significantly larger (8·5 ± 2·4 vs 3·5 ± 1·0, P = 0·002), presented in older patients and showed relatively higher incidence in males. Mitotic figure counts were significantly lower (0·39 ± 0·04 vs 0·93 ± 0·11 in ACA, P = 0·001) and revealed higher frequency of apoptotic cells (100% vs 9% in ACA, P = 0·001). The USP of ACA-RML showed no diagnostic features of ACC. No differences from ACA were significant, but there was a tendency towards lower dehydroepiandrosterone DHA and DHA metabolites.

CONCLUSIONS

ACA-RML reveals distinctive histological features and lack of USP markers of malignancy. More cases of this rare tumour may confirm differences from ACA in steroid excretion. It is important to recognize ACA-RML because its size and heterogeneous appearance raise the possibility of ACC.

Structure elucidation of the diagnostic product ion at m/z 97 derived from androst-4-en-3-one-based steroids by ESI-CID and IRMPD spectroscopy

Structure elucidation of steroids by mass spectrometry has been of great importance to various analytical arenas and numerous studies were conducted to provide evidence for the composition and origin of (tandem) mass spectrometry-derived product ions used to characterize and identify steroidal substances. The common product ion at m/z 97 generated from androst-4-ene-3-one analogs has been subject of various studies, including stable isotope-labeling and (high resolution/high accuracy) tandem mass spectrometry, but its gas-phase structure has never been confirmed. Using high resolution/high accuracy mass spectrometry and low resolution tandem mass spectrometry, density functional theory (DFT) calculation, and infrared multiple photon dissociation (IRMPD) spectroscopy employing a free electron laser, the structure of m/z 97 derived from testosterone was assigned to protonated 3-methyl-2-cyclopenten-1-one. This ion was identified in a set of six cyclic C(6)H(9)O(+) isomers as computed at the B3LYP/6-311++G(2d,2p) level of theory (protonated 3-methyl-2-cyclopenten-1-one, 2-methyl-2-cyclopenten-1-one and 2-cyclohexen-1-one). Product ions of m/z 97 obtained from MS(2) and MS(3) experiments of protonated 3-methyl-2-cyclopenten-1-one, 2-methyl-2-cyclopenten-1-one, 2-cyclohexen-1-one, and testosterone corroborated the suggested gas-phase ion structure, which was eventually substantiated by IRMPD spectroscopy yielding a spectrum that convincingly matched the predicted counterpart. Finally, the dissociation pathway of the protonated molecule of testosterone to m/z 97 was revisited and an alternative pathway was suggested that considers the exclusion of C-10 along with the inclusion of C-5, which was experimentally demonstrated with stable isotope labeling.

Clinicopathological features, biochemical and molecular markers in 5 patients with adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a very rare malignant tumor with poor prognosis. To gain insight into the pathogenic significance of ACC, we studied clinicopathological features and gene expression profile in ACC. We analyzed five ACC cases (two men and three women) with the median age of 45-year-old who underwent adrenalectomy at our institute. Endocrine studies revealed that two cases had subclinical Cushing's syndrome (SCS) and one with concomitant estrogen-secreting tumor, while the rest of three cases had non-functioning tumors. Analysis of urinary steroids profile by gas chromatography/mass spectrometry showed increased metabolites of corticosteroid precursors, such as 17-OH pregnenolone, 17-OH progesterone, dehydroepiandorosterone (DHEA), and 11-deoxycortisol in all five cases. The pathological diagnosis of ACC was based on Weiss's criteria with its score ≥ 3. The mean size of the resected tumors was 87 mm and Ki67/MIB1 labeling index, a proliferative marker, was 3-27%. Immunohistochemical analysis revealed a disorganized expression of several steroidogenic enzymes, such as 3β-hydroxysteroid dehydrogenase, 17α-hydroxylase, and DHEA-sulfotransferase. Among several genes determined by RT-PCR, insulin-like growth factor (IGF)-II mRNA was consistently and abundantly expressed in all 5 tumor tissues. Postoperatively, two cases with SCS developed local recurrence and liver metastasis. The present study suggests that the disorganized expression of steroidogenic enzymes and the overexpression of IGF-II by the tumor are hallmarks of ACC, which could be used as biochemical and molecular markers for ACC.

Expression of the ACTH receptor, steroidogenic acute regulatory protein, and steroidogenic enzymes in canine cortisol-secreting adrenocortical tumors

Studies of human adrenocortical tumors (ATs) causing Cushing's syndrome suggest that hypersecretion of cortisol is caused by altered expression of steroidogenic enzymes and that steroidogenesis can only be maintained when there is expression of the ACTH receptor (ACTH-R). Here we report the screening for the mRNA expression of the ACTH-R, steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase, 21-hydroxylase (all in 38 cortisol-secreting ATs), 17α-hydroxylase, and 11β-hydroxylase (both in 28 cortisol-secreting ATs). Real-time PCR (RT-PCR) was applied in all samples and was compared with that in normal canine adrenal glands. Messenger-RNA encoding StAR, steroidogenic enzymes, and ACTH-R were present in both normal adrenal glands and cortisol-secreting ATs. The amounts of mRNA encoding StAR and enzymes of the steroidogenic cluster needed for cortisol production did not differ significantly between either adenomas or carcinomas and normal adrenal glands. The amount of mRNA encoding ACTH-R was significantly lower in carcinomas than in normal adrenal glands (P = 0.008). In conclusion, RT-PCR analysis revealed no overexpression of StAR and steroidogenic enzymes in canine cortisol-secreting ATs. Significant downregulation of ACTH-R in carcinomas might be associated with the malignant character of the AT.

Urinary corticoid: creatinine ratios in dogs with pituitary-dependent hypercortisolism during trilostane treatment

BACKGROUND

The adrenocorticotropic hormone (ACTH) stimulation test is used to evaluate trilostane treatment in dogs with hypercortisolism.

HYPOTHESIS

The urinary corticoid : creatinine ratio (UCCR) is a good alternative to the ACTH stimulation test to determine optimal trilostane dose.

ANIMALS

Eighteen dogs with pituitary-dependent hypercortisolism.

METHODS

In this prospective study, the dose of trilostane was judged to be optimal on the basis of resolution of clinical signs of hypercortisolism and results of an ACTH stimulation test. The owners collected urine for determination of UCCR at 2-week intervals for at least 8 weeks after achieving the optimal trilostane dose.

RESULTS

The UCCRs were significantly higher before treatment (11.5-202.0 x 10(-6); median, 42.0 x 10(-6)) than at rechecks 2 months after optimal dosing, but they did not decrease below the upper limit of the reference range in the majority of dogs. The UCCRs of 11 dogs that initially were dosed insufficiently (range, 7.5-79.0 x 10(-6); median, 31.0 x 10(-6)) did not differ significantly from UCCRs when the dosage was optimal (8.2-72.0 x 10(-6); median, 33.0 x 10(-6)). Post-ACTH cortisol concentrations did not correlate significantly with UCCRs at rechecks during trilostane treatment. Long-term follow-up indicated that the decrease in UCCR below the upper limit of the reference was associated with hypocortisolism.

CONCLUSION AND CLINICAL IMPORTANCE

The UCCR cannot be used as an alternative to the ACTH stimulation test to determine the optimal dose of trilostane, but might be helpful in detecting dogs at risk for developing hypocortisolism during trilostane treatment.

Cortisol assays and diagnostic laboratory procedures in human biological fluids

The overview of cortisol physiology, action and pathology is achieved in relation to the hypothalamic-pituitary-adrenal axis alteration by laboratory investigation. The measurements of cortisol and related compound levels in blood, urine and saliva used to study the physiological and pathological cortisol involvement, are critically reviewed. The immunoassay and chromatographic methods for cortisol measurement in the various biological fluids are examined in relation to their analytical performances, reference ranges and diagnostic specificity and sensitivity. Moreover, blood, urine and saliva cortisol level measurements are described taking into account the diagnostic implications. The deduction is that each method requires the definition of its own reference range and its related diagnostic cut-off levels. Thus, this review, stressing the analysis procedures, could help to understand and compare the results of the different assays.

Reference intervals of urinary steroid metabolites using gas chromatography-mass spectrometry in Chinese adults

BACKGROUND

Urinary steroid profiling by GC or GC-MS are established clinical tools to complement other biochemical tests in the diagnosis and investigation of a wide range of adrenocortical disorders, but normative data on adults using the more specific GC-MS are lacking. Our objective was to set up the reference intervals of commonly detected urinary steroid metabolites as well as marker metabolites seen in disease states.

METHOD

Apparently healthy adult Chinese males and females were recruited by completing health questionnaires. A 24-h urine specimen was collected from all the participants for urinary steroid profiling by GC-MS in cyclic scan mode. The analyzer was calibrated by using authentic steroid standards. Statistical methods recommended by the National Committee for Clinical Laboratory Standards were followed for setting up the reference intervals of various steroid metabolites. After outliers were excluded, the data were tested for the necessity to partition into sex-, menopausal status- and age-specific reference intervals.

RESULTS

83 males and 89 females were recruited for the study. Necessity to partition into sex-specific reference intervals was demonstrated for almost all steroid metabolites. Menopausal status and age also had a significant impact on steroid metabolite excretion, making separate reference intervals necessary.

CONCLUSIONS

We have set up the normative data on the levels of urinary steroid metabolite excretion in Chinese adults for future reference in patient management and research in steroid metabolism.

A case of estrogen-secreting adrenocortical carcinoma with subclinical Cushing's syndrome

A 25-year-old man was found to have a large right adrenal mass detected by abdominal echography and computed tomography, and presented with a mild gynecomastia. Endocrine study showed increased serum concentrations and urinary excretion of estrogens and dehydroepiandorosterone sulfate (DHEA-S). The patient had no Cushingoid features but autonomous cortisol secretion, compatible with the diagnosis of subclinical Cushing's syndrome. Surgical removal of the adrenal tumor led to normalization of serum and urinary excretion of estrogens and DHEA-S. Histopathological examination revealed a high-grade adrenocortical carcinoma (ACC). The disorganized expression of all the steroidogenic enzymes in individual tumor cells was demonstrated by immunohistochemical analysis, and the abundant expression of both aromatase mRNA and insulin-like growth factor (IGF)-II mRNA was shown by RT-PCR. These data suggest the excessive secretion of estrogen as well as the ineffective steroidogenesis by the adrenal tumor. This is a very rare case of estrogen-secreting ACC associated with subclinical Cushing's syndrome.

An 88-year-old woman diagnosed with adrenal tumor and congenital adrenal hyperplasia: connection or coincidence?

An 88-yr-old woman presented with a 3x4x5 cm adrenal incidentaloma. Apart from partial cortisol deficiency there were no clinical or laboratory signs of abnormal hormone production. Because of suspicion of carcinoma, a urinary steroid profile was carried out which indicated 21-hydroxylase deficiency with elevated pregnantriol. Biopsy of the tumor showed benign adenoma tissue. The genetic analysis showed two mutations in the CYP21-gene, V281L and 1172N consistent with mild non-classic congenital adrenal hyperplasia (CAH). The patient showed a general improvement with a low prednisolone dose. Previous reports have shown increased prevalence of CAH in patients with adrenal tumors although, to our knowledge, no one has reported the combination in a patient as old as in ours. Thus, clinical signs and symptoms of CAH should be looked for in patients with adrenal incidentalomas, even in the very old ones, and if suspicion further diagnostic work-up should be carried out to provide adequate treatment and follow-up.

Gene array analysis of macronodular adrenal hyperplasia confirms clinical heterogeneity and identifies several candidate genes as molecular mediators

Corticotropin (ACTH)-independent macronodular adrenal hyperplasia (AIMAH) is a heterogeneous condition in which cortisol secretion may be mediated by gastrointestinal peptide (GIP), vasopressin, catecholamines and other hormones. We studied the expression profile of AIMAH by genomic cDNA microarray analysis. Total RNA was extracted from eight tissues (three GIP-dependent) and compared to total RNA obtained from adrenal glands from 62 normal subjects. Genes had to be altered in 75% of the patients, and be up- or downregulated at a cutoff ratio of at least 2.0; 82 and 31 genes were found to be consistently up- and downregulated, respectively. Among the former were regulators of transcription, chromatin remodeling, and cell cycle and adhesion. Downregulated sequences included genes involved in immune responses and insulin signaling. Hierarchical clustering correlated with the two main AIMAH diagnostic groups: GIP-dependent and non-GIP-dependent. The genes encoding the 7B2 protein (SGNE1) and WNT1-inducible signaling pathway protein 2 (WISP2) were specifically overexpressed in the GIP-dependent AIMAH. For these, and six more genes, the data were validated by semiquantitative amplification in samples from a total of 32 patients (the original eight, six more cases of AIMAH, and 18 other adrenocortical hyperplasias and tumors) and the H295R adrenocortical cancer cell line. In conclusion, our data confirmed AIMAH's clinical heterogeneity by identifying molecularly distinct diagnostic subgroups. Several candidate genes that may be responsible for AIMAH formation and/or progression were also identified, suggesting pathways that affect the cell cycle, adhesion and transcription as possible mediators of adrenocortical hyperplasia.

Mutation analysis of CYP11B1 and CYP11B2 in patients with increased 18-hydroxycortisol production

BACKGROUND

In patients with glucocorticoid remediable aldosteronism (GRA), a rare hypertensive disorder caused by the presence of a chimeric aldosterone synthase (CYP11B2) and 11beta-hydroxylase (CYP11B1) gene, high level of urinary 18-hydroxycortisol (18OHF) excretion are observed. In some patients with hypertension, increased urinary 18OHF secretion is also found in the absence of the hybrid CYP11B1/CYP11B2 gene. We hypothesised that gene variants of CYP11B1 or CYP11B2 may be linked to this abnormal glucocorticoid production.

METHODS

The urinary steroid profile was analysed by gas chromatography/mass spectrometry in 429 hypertensive patients and 98 (23%) thereof tested positive for increased 18OHF excretion. After correction for total cortisol excretion, 12 subjects showed an abnormally high 18OHF excretion. For genotyping DNA was obtained from six of these patients. All were tested negative for the hybrid CYP11B1/CYP11B2 gene and were further analysed for mutations in all exons and promoter regions of both CYP11B1 and CYP11B2 by single strand conformation polymorphism (SSCP) and sequencing when appropriate.

RESULTS

The genetic analysis of the two genes revealed the presence of nine molecular variants in CYP11B2 and three in CYP11B1. In addition to published polymorphic sites, we identified two new variants in CYP11B2 but no new variants in CYP11B1. The newly identified CYP11B2 mutations are a C/T single nucleotide exchange located in the first intron and a double nucleotide exchange at the 3'-splice site of exon 8. The mutated sequence corresponds to the sequence of CYP11B1 indicating a gene conversion. This suggests that the mutant is not likely to affect splicing. Thus, none of the genetic variants identified explains the high urinary excretion of 18OHF.

CONCLUSIONS

We present here a complete method for the genetic analysis of the CYP11B1 and CYP11B2 genes. By this method we could not identify genetic variants responsible for a GRA-like phenotype. The presence of high levels of 18OHF should not be used alone as a diagnosis tool for GRA.

Adrenal cortical tumours: 25 years' experience at the Royal Children's Hospital, Melbourne

AIMS

Adrenal cortical tumours remain a rare entity with inconsistent consensus about treatment and follow up. This article reviews 25 years of experience in the Royal Children's Hospital, Melbourne, Australia.

METHODS

All records with the diagnosis of adrenal adenoma or carcinoma between 1976 and 2001 were reviewed, excluding tumours of the adrenal medulla. Details were recorded for age, gender, family history, presentation, biochemistry, imaging, histology, diagnosis, treatment and outcome.

RESULTS

Twelve children (six boys, six girls) were diagnosed with adrenal cortical tumours in this period. Median age at diagnosis was 2.5 years (range 0.5-15.6 years). Six of the 12 children presented with virilization. The remaining six identified by ultrasound performed for hemi-hypertrophy (2), hypertension (2), and fever with abdominal pain (2). Five children had a family history of tumour and two of these five had a p53 mutation demonstrated on molecular genetic analysis. Tumours in five of the 12 children were defined as malignant on histology. Surgery was deemed curative in nine cases. Only one case required further surgery and two required chemotherapy. Time since diagnosis ranged from 1 to 25.8 years. Two children died from complications of the tumour. One other child died following development of a second tumour.

CONCLUSION

Adrenal cortical tumours should always be considered in the differential for adrenal hormone excess. New information provided by mutational analysis may predict ongoing risks. Lifelong regular follow up is required.

Current management of incidentally discovered adrenal masses, with a review of Japanese literature

It is becoming increasingly common to discover adrenal masses incidentally on radiologic imaging studies. We herein present our experience with 61 cases of incidentally discovered and surgically removed adrenal incidentalomas, including 11 pheochromocytomas. Only four were adrenocortical carcinomas. A review of the literature, including Japanese journals, for the prevalence of incidentantally discovered adrenal mass, their differential diagnosis and management are discussed.