Rare neuroendocrine tumours may be misdiagnosed as Cushing’s disease

By Eleanor McDermid, Senior medwireNews Reporter

Ectopic tumours secreting corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) are very rare in children and can result in a misdiagnosis of Cushing’s disease (CD), say researchers.

Three of the patients in the reported case series had pituitary hyperplasia and underwent transsphenoidal surgery for apparent CD before the tumour that was actually causing their symptoms was located. The hyperplasia was probably caused by release of CRH from the ectopic tumour, which stimulated the pituitary gland, giving the impression of an ACTH-secreting pituitary adenoma, explain Maya Lodish (National Institutes of Health, Bethesda, Maryland, USA) and study co-authors.

These three patients were part of a series of seven, which Lodish et al describe as “a relatively large number of patients, considering the infrequency of this disease.”

The patients were aged between 1.8 and 21.3 years. Three had neuroendocrine tumours located in the pancreas ranging in size from 1.4 to 7.0 cm, two had thymic carcinoids ranging from 6.0 mm to 11.5 cm, one patient had a 12.0 cm tumour in the liver and one had a 1.3 cm bronchogenic carcinoid tumour of the right pulmonary lobe.

Four of the patients had metastatic disease and, during up to 57 months of follow-up, three died of metastatic disease or associated complications and two patients had recurrent disease.

“Our series demonstrates that these are aggressive tumors with a high mortality rate,” write the researchers in the Journal of Clinical Endocrinology & Metabolism. “It is important to follow the appropriate work up, regarding both biochemical and imaging tests, which can lead to the correct diagnosis and to the most beneficial therapeutic approach.”

The team found the CRH stimulation test to be helpful, noting, for example, that none of the patients had a rise in cortisol that was consistent with CD, with all patients showing smaller responses ranging from 2% to 15%. Likewise, just one patient had an ACTH rise higher than 35% on CRH administration, and four patients had a “flat” response, which has previously been associated with ectopic neuroendocrine tumours.

Of note, six patients had normal or high plasma CRH levels, despite all having high cortisol levels, which would be expected to result in undetectable plasma CRH due to negative feedback, implying another source of CRH production. Five patients had blunted diurnal variation of both cortisol and ACTH levels consistent with Cushing’s syndrome.

The patients also underwent a variety of imaging procedures to identify the source of ACTH/CRH production, some of which, such as octreotide scans, are specialist and not available in most hospitals, the researchers note, potentially contributing to inappropriate diagnosis and management.

From http://www.news-medical.net/news/20141030/Rare-neuroendocrine-tumours-may-be-misdiagnosed-as-Cushinge28099s-disease.aspx

Cushing Syndrome in Children: Growth after Surgical Cure

Cushing syndrome (CS) occurs only rarely in children, but when it does, it causes weight gain and stunting. In young children, adrenal tumors are usually the cause while in adolescents, pituitary tumors are more likely.

The September 2014 issue of Endocrine-Related Cancer examines growth patterns in 19 pediatric patients with ACTH-dependent CS (CD) and 18 patients with a form of ACTH-independent CS, micronodular adrenal hyperplasia (MAH). The researchers gathered data at the time of surgery and also followed up one year later.

Patients in the CD and the MAH groups had similar demographic characteristics, baseline heights and BMI scores before surgery. All patients experienced significant improvements in height and BMI after surgery. Patients with MAH, however, fared significantly better than those with CD and had better post-operative growth.

The researchers propose several reasons:

  • When ACTH-secreting pituitary adenoma requires extensive surgical exploration, remaining pituitary cells often lose some of their function.
  • CD patients tend to be older and have consistent and increased glucocorticoid exposure; they develop vertebral fractures more often leading to compromised skeletal and overall growth potential. MAH patients often have cyclical CS, with intermittent hypercortisolism and an overall milder CS.
  • CD patients often need a longer-than-expected course of therapy with steroids after surgery, which alters metabolism and growth.
  • CD patients have been shown to have advance bone age because of ACTH-induced metabolic changes.

The authors indicate that CS patients are often considered for growth hormone therapy once the underlying problem is corrected. They remind clinicians that MAH patients are less likely to need growth hormone. They recommend close monitoring for CD patients, and early intervention with growth hormone if growth does not meet expectation. –

See more at: http://www.hcplive.com/articles/Cushing-Syndrome-in-Children-Growth-after-Surgical-Cure

Mutation of ARMC5 gene characterized as the cause of meningeal tumour growth

Scientists at the Luxembourg Centre for Systems Biomedicine (LCSB) of the University of Luxembourg have published their findings that mutations in a gene known as “ARMC5” promote the growth of benign tumours in the adrenal glands and on the meninges: ARMC5 appears to belong to the group of so-called tumour suppressor genes. It is the first time in years that scientists have characterized such a gene.

The ARMC5 gene was discovered by independent workgroups studying – so-called adrenal adenomas – in connection with Cushing’s syndrome. In this disease, the body produces too much of the . Now, for the first time, a mutation of ARMC5 has been characterized as the cause behind the growth of meningeal tumours. The results on this tumour syndrome, obtained by the group of Dr. Patrick May and PD. Dr. Jochen Schneider together with colleagues from Charité Berlin (Dr. Ulf Elbelt) and the Universities of Würzburg (Prof. Dr. Bruno Allolio) and Cologne (Dr. Michael Kloth), have been published recently in the Journal of Clinical Endocrinology Metabolism.

Cortisol is an important hormone. It influences many metabolic pathways in the body and has a suppressing effect on the immune system. Accordingly, it is commonly employed as an anti-inflammatory medication. Prolonged, elevated levels of cortisol in the body can lead to obesity, muscular dystrophy, depression and other symptoms. To maintain the correct concentration in the blood, the body has a refined regulation system: Certain areas of the brain produce the hormone corticotropin as a stimulator of cortisol release; the actual formation of cortisol takes place in the . As the concentration of cortisol in the blood rises, the brain reduces the production of corticotropin.

In search of the causes of Cushing’s syndrome, scientists recently encountered certain genetic causes of benign tumours of the adrenal cortex. Growth of these adrenal cortex adenomas is based on a combination of hereditary and spontaneous mutations: It affects people in whom one of two “alternative copies” – one of the so-called alleles – of the ARMC5 gene is mutated from birth. If the second allele of ARMC5 later also undergoes a spontaneous mutation in the adrenal cortex, then the gene no longer functions. “What is interesting is that the failure of ARMC5 has no direct influence on cortisol production. However, because the tumour cells multiply faster than other body cells, and the number of cells in the tumour increases, the blood cortisol level rises in the course of the disease”, says Dr Schneider. Then, the level in the body rises and ultimately results in the onset of Cushing’s syndrome.

When other scientific workgroups discovered that further benign tumours – in this case meningeal tumours – occur more often in ARMC5-Cushing families, the group of Patrick May and Jochen Schneider sequenced the ARMC5 gene and studied it using bioinformatic techniques. “We demonstrated for the first time, in a patient with an adrenal cortex tumour and simultaneously a meningeal tumour, that somatic, that is non-hereditary, ARMC5 mutations are present in both tumours. This observation suggests that ARMC5 is a true tumour-suppressor gene.”

It must now be explored, Schneider continues, to what extent patients with adrenal cortex tumours ought to be screened for simultaneous presence of meningioma, and in which other types of tumour ARMC5 mutations are responsible for tumour growth: “Building upon that, we can learn whether the gene and the metabolic pathways it influences offer new approaches for treating the tumour syndrome.”

More information: “Molecular and Clinical Evidence for an ARMC5 Tumor Syndrome: Concurrent Inactivating Germline and Somatic Mutations are Associated with both Primary Macronodular Adrenal Hyperplasia and Meningioma.” Journal of Clinical Endocrinology Metabolism, October 2014. DOI: 10.1210/jc.2014-2648

Journal reference: Journal of Clinical Endocrinology & Metabolism search and more info website

Provided by University of Luxembourg search and more info

From http://medicalxpress.com/news/2014-10-mutation-armc5-gene-characterized-meningeal.html

Use late-night salivary cortisol to catch recurrent Cushing’s


AT ICE/ENDO 2014


CHICAGO – Late-night salivary cortisol exceeded normal limits in 10 women with recurrent Cushing’s disease a mean of 3.5 years after transsphenoidal surgery, but their urinary free cortisol remained in normal limits, according to a retrospective review from the Medical College of Wisconsin, Milwaukee.

That adds strength to the notion that late-night salivary cortisol (LNSC) catches recurrent Cushing’s that’s missed by urinary free cortisol, even though UFC remains a standard screening approach in some places.

The study is tiny and retrospective, but at the joint meeting of the International Congress of Endocrinology and the Endocrine Society, lead investigator Dr. Ty Carroll explained why the findings still matter, and also why two LNSC measurements are better than one.

Video: http://www.clinicalendocrinologynews.com/home/article/video-use-late-night-salivary-cortisol-to-catch-recurrent-cushings/d7fad98e9289f9402034e73455b7560c.html

Clinical effectiveness of metyrapone monotherapy in 195 patients with Cushing’s syndrome

From Day 1 of the 16th International Congress of Endocrinology and the Endocrine Society’s 96th Annual Meeting and Expo »

Chicago, IL – June 21, 2014

E Daniel, SJB Aylwin, SG Ball, K Boelaert, D Cuthbertson, C Daousi, JR Davis, W Drake, AB Grossman, M Gurnell, N Karavitaki, T Kearney, K Meeran, A Rees, PJ Trainer, JDC Newell-Price

Summary: Metyrapone is widely used in the UK for the control of cortisol excess in Cushing’s syndrome, but its use is not standardised. The few published reports on metyrapone use pertain to limited patient numbers. In this report, the largest report on metyrapone use, metyrapone was effective in achieving eucortisolemia in over 70% of patients without any other cortisol-lowering intervention, with a satisfactory safety profile. A variety of monitoring regimens were used, but greater standardisation of practice and more active dose titration is needed.

Methods:

  • A retrospective survey was conducted across 13 tertiary centres in England and Wales.
  • Using a standardised proforma, extensive data including monitoring and safety information were collected for patients with Cushing’s syndrome on metyrapone therapy between 1997 and 2013.
  • Eucortisolemia was defined according to the monitoring test used as a mean cortisol ‘day curve’ value ≤300 nmol/l, a urinary free cortisol bellow the upper limit of normal (ULN) or a 9am serum cortisol

Results:

  • A total of 195 patients received metyrapone (160 as monotherapy). Average age was 49.6 +/-15.7 years: 87.2% had metyrapone in conjunction with other interventions (surgery, radiotherapy or chemotherapy) while 12.8% had cortisol-lowering treatment alone.
  • Dose-titration was used in 81% of patients, whereas 19% had a block-and-replace regimen.
  • A total of 138 patients received metyrapone monotherapy for a mean duration of 162 days before any other intervention took place.
  • The etiology of Cushing’s syndrome in this subgroup was: pituitary-dependent disease [CD, 59% (macroadenoma 32% of CD)], ectopic ACTH syndrome (EAS, 17%), adrenocortical carcinoma (ACC, 4%), adrenal adenoma (AA, 17%) and other benign adrenal disease (3%).
  • Hypokalemia was actively managed with potassium levels increasing during metyrapone therapy (3.90 mmol/L vs 3.68 mmol/L, P=0.0026).
  • In this subgroup, 74% achieved eucortisolemia on varying doses: CD 1370 mg, EAS 2080 mg, AA 1170 mg, ACC 750 mg daily in divided doses.
  • The preferred monitoring method was by cortisol ‘day-curves’, followed by 9am cortisol and urinary free cortisol.
  • Overall, 25.3% of patients developed side effects, most commonly gastrointestinal upset and hypoadrenalism.
  • 88% of adverse events were managed as outpatients; 36% of patients treated for more than one month had ≤2 monitoring assessments and insufficient dose titration.

From MDLinx