Cushing's syndrome is considered a rare disease and its diagnosis can be challenging. Establishment of evidence-based recommendations is difficult. In 2008, several national and international consensus recommendations for the diagnosis or management of Cushing's syndrome were reported. The Endocrine Society, with the participation of the European Society of Endocrinology, has developed a task force to update recommendations for the diagnosis of Cushing's syndrome. The main aspects of these recommendations are presented in this article and discussed in the context of current research efforts in Europe focusing on the improvement of diagnosis and management of rare diseases including adrenal disorders such as Cushing's syndrome.
Laurence Guignat and Jérôme Bertherat
Rossella Libé and Jérôme Bertherat
Adrenal masses can be detected in up to 4% of the population, and are mostly of adrenocortical origin. Adrenocortical tumours (ACTs) may be responsible for excess steroid production and, in the case of adrenocortical cancers, for morbidity or mortality due to tumour growth. Our understanding of the pathogenesis of ACTs is more limited than that for other tumours. However, studies of the genetics of ACTs have led to major advances in this field in the last decade. The identification of germline molecular defects in the hereditary syndrome responsible for ACTs has facilitated progress. Indeed, similar molecular defects have since been identified as somatic alterations in sporadic tumours. The familial diseases concerned are Li–Fraumeni syndrome, which may be due to germline mutation of the tumour-suppressor gene TP53 and Beckwith–Wiedemann syndrome, which is caused by dys-regulation of the imprinted IGF-II locus at 11p15. ACTs also occur in type 1 multiple endocrine neoplasia (MEN 1), which is characterized by a germline mutation of the menin gene. Cushing’s syndrome due to primary pigmented nodular adrenocortical disease (PPNAD) has been observed in Carney complex patients presenting inactivating germline PRKAR1A mutations. Interestingly, allelic losses at 17p13 and 11p15 have been demonstrated in sporadic adrenocortical cancer and somatic PRKAR1A mutations have been found in secreting adrenocortical adenomas. More rarely, mutations in Gs protein (gsp) and the gene for ACTH receptor have been observed in ACTs. The genetics of another group of adrenal diseases that can lead to adrenal nodular hyperplasia – congenital adrenal hyperplasia (CAH) and glucocorticoid-remediable aldosteronism (GRA) – have also been studied extensively. This review summarizes recent advances in the genetics of ACTs, highlighting both improvements in our understanding of the pathophysiology and the diagnosis of these tumours.
Delphine Vezzosi and Jérôme Bertherat
The cAMP–protein kinase A pathway plays a central role in the development and physiology of endocrine tissues. cAMP mediates the intracellular effects of numerous peptide hormones. Various cellular and molecular alterations of the cAMP-signaling pathway have been observed in endocrine diseases.
Phosphodiesterases (PDEs) are key regulatory enzymes of intracellular cAMP levels. Indeed, PDEs are the only known mechanism for inactivation of cAMP by catalysis to 5′-AMP. It has been suggested that disruption of PDEs could also have a role in the pathogenesis of many endocrine diseases. This review summarizes the most recent advances concerning the role of the PDEs in the physiopathology of endocrine diseases. The potential significance of this knowledge can be easily envisaged by the development of drugs targeting specific PDEs.
Lucas Bouys and Jérôme Bertherat
Described for the first time in 1985, Carney complex (CNC) is a rare dominantly inherited multiple neoplasia syndrome with almost full penetrance and characterized by both endocrine – primary pigmented nodular adrenocortical disease with Cushing’s syndrome, acromegaly and thyroid tumors – and non-endocrine manifestations such as cardiac, cutaneous and mucosal myxomas, pigmented cutaneous lesions, psammomatous melanotic schwannoma, osteochondromyxoma and a wide range of other tumours with potential malignancy. The pathophysiology of CNC is a model of dysregulation of the cAMP/PKA signalling in human diseases. As described 20 years ago, inactivating heterozygous mutations of PRKAR1A formerly known as CNC1, encoding the regulatory subunit 1α of protein kinase A, are identified in more than 70% of the index cases, while inactivating mutations of genes encoding phosphodiesterases are found in rare and particular forms of the complex. There is at present no medical specific treatment for CNC, every confirmed or suspected CNC patient should be managed by a multi-disciplinary team according to each manifestation of the disease and offered a long-term follow-up and genetic counselling. The better knowledge that we have now of this fascinating rare disease and its genetics will help to improve patients outcome.
Ludivine Drougat, Stéphanie Espiard, and Jerôme Bertherat
Long-term consequences of cortisol excess are frequent despite appropriate treatment after cure of Cushing's syndrome. This might be due to diagnostic delay, often difficult to reduce in rare diseases. The identification of a genetic predisposing factor might help to improve early diagnosis by familial screening. Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a rare cause of Cushing's syndrome. Hypercortisolism in PBMAH is most often diagnosed between the fifth and sixth decades of life. The bilateral nature of the adrenocortical tumors and the occurrence of rare clear familial forms suggest a genetic origin. Indeed, a limited subset of PBMAH can be observed as part of multiple tumors syndromes due to alterations of the APC, Menin or Fumarate Hydratase genes. Rare variants of the phosphodiesterases PDE11A have been associated with PBMAH. The recent identification of ARMC5 germline alterations in 25–50% of PBMAH patients without obvious familial history or associated tumors opens new perspectives. ARMC5 alterations follow the model of a tumor suppressor gene: a first germline inactivating mutation of this 16p located gene is followed by a somatic secondary hit on the other allele (inactivating mutation or allelic loss). Functional studies demonstrate that ARMC5 controls apoptosis and steroid synthesis. The phenotype of index cases patients with the mutation seems more severe than the one of WT index cases. However, phenotype variability within a family is often observed. This review summarizes the genetics of PBMAH, focusing on ARMC5, which offer new perspectives for early diagnosis of Cushing's syndrome.
Jérôme Bertherat, Marie Thérèse Bluet-Pajot, and Jacques Epelbaum
Bertherat J, Bluet-Pajot MT, Epelbaum J. Neuroendocrine regulation of growth hormone. Eur J Endocrinol 1995;132:12–24. ISSN 0804–4643
This short review is focused on the neuroendocrine regulation of growth hormone (GH) pulsatile secretory pattern and GH gene expression. The neuronal network involved in the central control of GH includes extrahypothalamic neurons such as the noradrenergic and cholinergic systems, which regulate the two antagonistic neurohormonal systems: somatostatin (SRIH) and GH-releasing hormone (GHRH). Intrahypothalamic Proopiomelanocortin- and Galanin-containing interneurons also participate in the regulation of SRIH and GHRH neuronal activity, which also is dependent on sex steroids and GH and/or insulin-like growth factor I (IGF-I) feedback. cAMP (controlled mainly by GHRH and SRIH), thyroid and glucocorticoid hormones, IGF-I and activin are among the factors that regulate GH gene expression at the transcriptional level and may play a role in somatotroph differentiation and proliferation during ontogeny as well as physiological and pathological states such as acromegaly.
J Epelbaum, U159 INSERM, Centre Paul Broca, 2 ter rue d'Alésia, 75014 Paris, France
François Moreau, Hervé Mittre, Annie Benhaim, Camille Bois, Jérome Bertherat, Serge Carreau, and Yves Reznik
The aromatase enzyme catalyzes the final stage of estrogen biosynthesis pathway from androgens. Its expression in the adrenal is poorly studied except for the rare estrogen-producing adrenocortical tumors. In order to further characterize aromatase expression in the adrenal, we evaluated the aromatase enzyme activity, Cyp19a1 gene expression level, and promoter utilization in normal adrenal tissues and in adrenocortical secreting tumors.
Design and methods
Six normal adult adrenals (NA), 2 feminizing adrenal tumors (FT), 10 cortisol-producing adenomas with overt (CS, n=4) or sub-clinical Cushing syndrome (SCS, n=6) and 3 aldosterone-producing adenomas (APA) were studied. Tissue aromatase activity was determined by the tritiated (3H)-water method. Total aromatase mRNA were measured by a competitive RT-PCR. Promoter regions PII and PI.4-derived transcripts were also studied in NA, FT, and other steroid-producing tumors by a semi-quantitative comparative RT-PCR. Immunofluorescence analysis was performed in normal human adrenal tissues.
Aromatase activity was detected in NA tissues and in all tumor subtypes, at high levels in both FT. In NA, aromatase immunofluorescence was detected in the cytoplasm of steroidogenic cells, mainly from zona reticularis. Compared with NA, aromatase transcript levels were similar in CS and APA, lower in SCS and similar or higher in FT. Promoter analysis suggested predominant PII utilization in NA, APA, and SCS, but similar PII and PI.4 utilization in CS tumors.
Aromatase is expressed at similar levels in normal adrenal and in adrenocortical tumors, but at variably high levels in FT. Different promoter utilization patterns are found among tumor subtypes.
Charlotte De Bucy, Laurence Guignat, Tanya Niati, Jérôme Bertherat, and Joel Coste
Health-related quality of life (HrQoL) is increasingly considered to be an important outcome of care for hypothalamic–pituitary–adrenal (HPA) axis dysregulation. The objective of this study was to assess the influence of type of HPA axis dysregulation and cortisol status on HrQOL and its evolution with time and treatment.
Prospective cohort study.
Between September 2007 and April 2014, HrQoL questionnaires were administered during routine management to all patients with HPA axis dysregulation hospitalized in a single department, and this was repeated after 6- 12-, 24- and 36-month during standard follow-up. The Medical Outcomes Study 36‐item short‐form health survey (SF‐36) and the General Health Questionnaire 12 (GHQ-12) were used simultaneously, with a common time schedule to measure the impact of HPA axis dysregulation on HrQoL. Multivariate mixed linear regression models were constructed to adjust for potential confounders.
343 patients (206 with Cushing’s syndrome of pituitary origin, 91 with Cushing’s syndrome of adrenal origin and 46 with Addison’s disease) responded to the questionnaires. Overall, HrQoL scores were well below population values. Cushing syndrome of pituitary origin was associated with worse HrQoL, especially in physical dimensions. More than half of the patients, of all diagnoses and cortisol status, had psychological distress requiring attention according to the GHQ-12. Hypercortisolism had the greatest negative influence on HrQoL.
HRQoL appears significantly altered by all forms of HPA axis dysregulation, and most substantially and broadly by Cushing’s syndrome, notably during periods of hypercortisolism. These effects on HRQoL deserve further consideration both in clinical practice and research.
Catarina B d'Alva, Gwenaelle Abiven-Lepage, Vivian Viallon, Lionel Groussin, Marie Annick Dugue, Xavier Bertagna, and Jerôme Bertherat
Adrenocortical tumors (ACT) account for no more than 0.2% of the causes of androgen excess (AE). Conversely, these rare tumors have a very poor prognosis. It is difficult and important to exclude this diagnosis whenever there is AE.
Retrospective investigation of androgen profiles in a large consecutive series of androgen-secreting (AS) ACT to assess their relative diagnostic value.
A total of 44 consecutive female patients with ACT-AS and a comparison group of 102 women with non-tumor causes of AE (NTAE).
Patients with ACT-AS were older than the ones with NTAE (37.7 vs 24.8 years; P<0.001) and the prevalence of hirsutism, acne, and oligo/amenorrhea were not different. Free testosterone was the most commonly elevated androgen in ACT-AS (94%), followed by androstenedione (90%), DHEAS (82%), and total testosterone (76%), and all three androgens were simultaneously elevated in 56% of the cases. Androgen serum levels became subnormal in all ACT-AS patients after complete tumor removal. In NTAE, the most commonly elevated androgen was androstenedione (93%), while all three androgens were elevated in only 22% of the cases. Free testosterone values above 6.85 pg/ml (23.6 pmol/l) had the best diagnostic value for ACT-AS (sensitivity 82%, confidence interval (CI): 57–96%; specificity 97%, CI: 91–100%). Basal LH and FSH levels were significantly lower in the ACT-AS group.
Free testosterone was the most reliable marker of ACT-AS. However, the large overlap of androgen levels between ACT-AS and NTAE groups suggests that additional hormonal and/or imaging investigations are required to rule out ACT-AS in case of increased androgens.
Roula Bou Khalil, Camille Baudry, Laurence Guignat, Carmen Carrasco, Jean Guibourdenche, Stéphane Gaillard, Xavier Bertagna, and Jérôme Bertherat
To describe the sequence of hormonal changes during recurrence of Cushing's disease (CD) after successful transsphenoidal surgery (TSS).
Retrospective study in a single center.
Patients and methods
We studied 101 of the 127 patients treated by TSS for CD between 1996 and 2009, who had hypocortisolism or eucortisolism for at least 3 months post-TSS. We arbitrarily defined ‘overt recurrence’, as presence of two classical parameters of excess cortisol (increased midnight – either serum or salivary – and 24 h urinary cortisol (UC)), leading to further specific therapeutic action, and ‘mild recurrence’, as presence of a single classical parameter, leading to simple surveillance.
Of the 101 patients, 21 (20.8%) presented with recurrence, ‘mild’ or ‘overt’, during long-term follow-up (median 50.4 months, range 7–99). Recurrence occurred less frequently (16.8 vs 50%, P=0.02), and later (mean 44.7 months, median 43, range 7–94 vs mean 21.5 months, median 17, range 3–61, P=0.05), in patients with early post-TSS hypocortisolism compared with those with eucortisolism. Increase in midnight cortisol occurred in a mean time of 38.2 months, while UC elevation was observed at 50.6 months. Vasopressin analogs and CRH tests were eventually positive in 85 and 93% of all patients respectively; a positive response to one of the two dynamic tests preceded the increase in midnight cortisol or UC in 71 and 64% of the patients respectively.
A positive response to vasopressin analogs and/or CRH tests occurs early in recurrence, followed by an increase in midnight cortisol, while UC elevation is at a later stage.