Paediatric Cushing syndrome: a prospective, multisite, observational cohort study

BACKGROUND

Paediatric endogenous Cushing syndrome is a rare condition with variable signs and symptoms of presentation. We studied a large cohort of paediatric patients with endogenous Cushing syndrome with the aim of describing anthropometric, clinical, and biochemical characteristics as well as associated complications and outcomes to aid diagnosis, treatment, and management.

METHODS

In this prospective, multisite cohort study, we studied children and adolescents (≤18 years at time of presentation) with a diagnosis of Cushing syndrome. Patients had either received their initial diagnosis and evaluation at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (Bethesda, MD, USA) or been referred from other centres in the USA or outside the USA. We collected participants' clinical, biochemical, and imaging findings and recorded their post-operative course until their latest appointment.

FINDINGS

Of 342 paediatric patients with a diagnosis of Cushing syndrome, 193 (56%) were female and 149 (44%) male. 261 (76%) patients had corticotroph pituitary neuroendocrine tumours (Cushing disease), 74 (22%) had adrenal-associated Cushing syndrome, and seven (2%) had ectopic Cushing syndrome. Patients were diagnosed at a median of 2 years (IQR 1·0-3·0) after the first concerning sign or symptom, and patients with adrenal-associated Cushing syndrome were the youngest at diagnosis (median 10·4 years [IQR 7·4-13·6] vs 13·0 years [10·5-15·3] for Cushing disease vs 13·4 years [11·0-13·7] for ectopic Cushing syndrome; p<0·0001). Body-mass index z-scores did not differ between the diagnostic groups (1·90 [1·19-2·34] for adrenal-associated Cushing syndrome vs 2·18 [1·60-2·56] for Cushing disease vs 2·22 [1·42-2·35] for ectopic Cushing syndrome; p=0·26). Baseline biochemical screening for cortisol and adrenocorticotropin at diagnosis showed overlapping results between subtypes, and especially between Cushing disease and ectopic Cushing syndrome. However, patients with ectopic Cushing syndrome had higher urinary free cortisol (fold change in median cortisol concentration from upper limit of normal: 15·5 [IQR 12·7-18·0]) than patients with adrenal-associated Cushing syndrome (1·5 [0·6-5·7]) or Cushing disease (3·9 [2·3-6·9]; p<0·0001). Common complications of endogenous Cushing syndrome were hypertension (147 [52%] of 281 patients), hyperglycaemia (78 [30%] of 260 patients), elevated alanine transaminase (145 [64%] of 227 patients), and dyslipidaemia (105 [48%] of 219 patients). Long-term recurrence was noted in at least 16 (8%) of 195 patients with Cushing disease.

INTERPRETATION

This extensive description of a unique cohort of paediatric patients with Cushing syndrome has the potential to inform diagnostic workup, preventative actions, and follow-up of children with this rare endocrine condition.

FUNDING

Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health & Human Development, National Institutes of Health.

Steroidogenic factor-1 lineage origin of skin lesions in Carney complex syndrome

Carney complex (CNC) is a rare familial multi-neoplastic syndrome predisposing to endocrine and non-endocrine tumors due to inactivating mutations of PRKAR1A leading to perturbations of the cAMP protein kinase A (PKA) signaling pathway. Skin lesions are the most common manifestation of CNC, including lentigines, blue nevi and cutaneous myxomas, in unusual locations such as oral and genital mucosa. Unlike endocrine disorders, the pathogenesis of skin lesions remains unexplained. Here, we show that embryonic invalidation of the Prkar1a gene in Steroidogenic Factor-1-expressing cells, leads to the development of familial skin pigmentation alterations reminiscent of those in patients. Immunohistological and molecular analyses coupled with genetic monitoring of recombinant cell lineages in mouse skin, suggest that familial lentiginosis and myxomas occurs in skin areas specifically enriched in dermal melanocytes. In lentigines and blue nevi-prone areas from mutant mice and patients, Prkar1a/PRKAR1A invalidation occurs in a subset of dermal fibroblasts capable of inducing, under the influence of PKA signaling, the production of pro-melanogenic EDN3 and HGF signals. Our model strongly suggests that the origin of the typical CNC cutaneous lesions is the result of non-cell-autonomous pro-melanogenic activity of a dermal fibroblast population sharing a community of origin with SF-1 lineage.

Protein kinase A drives paracrine crisis and WNT4-dependent testis tumor in Carney complex

Large-cell calcifying Sertoli cell tumors (LCCSCTs) are among the most frequent lesions occurring in male Carney complex (CNC) patients. Although they constitute a key diagnostic criterion for this rare multiple neoplasia syndrome resulting from inactivating mutations of the tumor suppressor PRKAR1A, leading to unrepressed PKA activity, LCCSCT pathogenesis and origin remain elusive. Mouse models targeting Prkar1a inactivation in all somatic populations or separately in each cell type were generated to decipher the molecular and paracrine networks involved in the induction of CNC testis lesions. We demonstrate that the Prkar1a mutation was required in both stromal and Sertoli cells for the occurrence of LCCSCTs. Integrative analyses comparing transcriptomic, immunohistological data and phenotype of mutant mouse combinations led to the understanding of human LCCSCT pathogenesis and demonstrated PKA-induced paracrine molecular circuits in which the aberrant WNT4 signal production is a limiting step in shaping intratubular lesions and tumor expansion both in a mouse model and in human CNC testes.

A Case of Carney Triad Complicated by Renal Cell Carcinoma and a Germline SDHA Pathogenic Variant

Background: Carney triad is a rare multiple-neoplasia syndrome presenting as an association of paragangliomas (PGL), gastrointestinal stromal tumors (GIST), and pulmonary chondromas (CHO). Succinate dehydrogenase deficiency has been associated with several neoplasias, including Carney triad, renal cell carcinoma (RCC) and those associated with hereditary PGL/ pheochromocytoma (PHEO) syndromes.

Clinical Case: A 57-year-old male diagnosed with hypertension at age 49, presented with a gradual increase in blood pressure over a period of 12 months. For seven years following his diagnosis of hypertension, the patient experienced episodic increases in blood pressure, to a systolic pressure greater than 180 mmHg associated with a tight band sensation around his forehead lasting half a day. Abdominal computed tomography (CT) revealed a left adrenal adenoma, a 5.1 cm para-aortic mass, and a right renal superior pole lesion measuring 2.5 cm, which was suspicious for a carcinoma. ¹²³I-metaiodobenzylguanidine (¹²³I-MIBG) and ¹⁸F-fluorodeoxyglucose-positron emission tomography (¹⁸F-FDG-PET) scans were performed, which suggested the para-aortic mass to be consistent with a PGL. Additionally, ¹⁸F-FDG uptake was noted in the gastroesophageal region and was suspicious for a GIST. The left adrenal mass was not associated with ¹²³I-MIBG or ¹⁸F-FDG activity. Chest CT demonstrated a right middle lobe lung lesion suggestive of a CHO, although no biopsy was performed. A diagnosis of Carney triad was made. The patient underwent surgical resection of the PGL and GIST, as well as a partial right nephrectomy. The PGL and GIST were positive for SDHA and negative for SDHB by immunohistochemical (IHC) staining. Pathology from the renal lesion was consistent with a 2.3 cm conventional clear cell renal carcinoma, with positive staining for SDHA and SDHB by IHC. The patient was found to harbor a germline heterozygous pathogenic variant (c.91 C>T, p.R31X) in SDHA which has been previously reported and results in loss of function of SDHA. SHDC hypermethylation was not detected in the PGL, GIST, or RCC. Additionally, DNA sequencing of the RCC did not indicate loss of heterozygosity at the variant region of interest. Although the SDHA disease-causing variant is responsible for the patients Carney triad phenotype, it is unclear if this variant is causative of the RCC.

Conclusion: This is a novel presentation of a germline inactivating SDHA pathogenic variant in a patient with Carney triad complicated by RCC. However, an SDHA disease-causing variant was previously reported in a patient with comorbid GIST and RCC. This case provides further support to the increasing evidence that SDHx pathogenic variants may predispose patients to develop renal neoplasms.

A case of Carney triad complicated by renal cell carcinoma and a germline SDHA pathogenic variant

SUMMARY

Succinate dehydrogenase deficiency has been associated with several neoplasias, including renal cell carcinoma (RCC) and those associated with hereditary paraganglioma (PGL)/ pheochromocytoma (PHEO) syndromes, Carney dyad, and Carney triad. Carney triad is a rare multitumoral syndrome characterized by co-existing PGL, gastrointestinal stromal tumor (GIST), and pulmonary chondroma (CHO). We report a case of a 57-year-old male who presented with para-aortic and gastroesophogeal masses, and a right renal superior pole lesion, which were classified as multiple PGLs, a GIST, and a clear cell renal carcinoma, respectively, on pathology following surgical resection. Additionally, a CHO was diagnosed radiologically, although no biopsy was performed. A diagnosis of Carney triad was made. SDHB immunohistochemical staining was negative for the PGL and the GIST, indicating SDH-deficiency. Interestingly, the renal cell carcinoma (RCC) stained positive for both SDHB and SDHA. Subsequent genetic screening of SDH subunit genes revealed a germline inactivating heterozygous SDHA pathogenic variant (c.91 C>T, p.R31X). Loss of heterozygosity was not detected at the tumor level for the RCC, which likely indicated the SDHA variant would not be causative of the RCC, but could still predispose to the development of neoplasias. To the knowledge of the authors this is the first reported case of an SDHA pathogenic variant in a patient with Carney triad complicated by RCC.

LEARNING POINTS

The succinate dehydrogenase enzyme is encoded by four subunit genes (SDHA, SDHB, SDHC, and SDHD; collectively referred to as SDHx), which have been implicated in several neoplasias and are classified as tumor suppressor genes. Carney triad is a rare multiple-neoplasia syndrome presenting as an association of PGLs, GISTs, and CHOs. Carney triad is most commonly associated with hypermethylation of SDHC as demonstrated in tumor tissue, but approximately 10% of cases are due to pathogenic SDHx variants. Although SDHB pathogenic variants are most commonly reported in SDH-deficient renal cell carcinoma, SDHA disease-causing variants have been reported in rare cases.

Curative resection of an aldosteronoma causing primary aldosteronism in the second trimester of pregnancy

SUMMARY

A 29-year-old primigravida woman with a known history of primary aldosteronism due to a right aldosteronoma presented with uncontrolled hypertension at 5 weeks of estimated gestation of a spontaneous pregnancy. Her hypertension was inadequately controlled with pharmacotherapy which lead to the consideration of surgical management for her primary aldosteronism. She underwent curative right unilateral adrenalectomy at 19 weeks of estimated gestational age. The procedure was uncomplicated, and her blood pressure normalized post-operatively. She did, however, have a preterm delivery by cesarean section due to intrauterine growth retardation with good neonatal outcome. She is normotensive to date.

LEARNING POINTS

Primary aldosteronism is the most common etiology of secondary hypertension with an estimated prevalence of 5-10% in the hypertensive population. It is important to recognize the subtypes of primary aldosteronism given that certain forms can be treated surgically. Hypertension in pregnancy is associated with significantly higher maternal and fetal complications. Data regarding the treatment of primary aldosteronism in pregnancy are limited. Adrenalectomy can be considered during the second trimester of pregnancy if medical therapy fails to adequately control hypertension from primary aldosteronism.

SAT-543 Human Hair Aldosterone Measurements for Evaluation of Primary Aldosteronism

Background: Primary Aldosteronism (PA) is the most common cause of endocrine hypertension in US. Diagnostic techniques such as a 24 hour urine collection or saline suppression test (SST) can be laborious for both patients and staff. Our group previously showed that human hair cortisol measurements correlated with urine and serum cortisol levels in patients with endogenous cortisol excess. In this study, we explored whether human hair aldosterone correlated with other measures of aldosterone production. Methods: 41 adult subjects were evaluated at the NIH Clinical Center for adrenal disorders. A pencil-width of hair near the occiput was removed, and the 1cm segment closest to the scalp was analyzed by enzyme immunoassay for aldosterone, reported as pg aldosterone/mg dry hair. Not all subjects underwent complete workup for PA. Data were transformed as necessary to maintain assumptions of normality. Student’s t-test and Pearson correlations were used for statistical analysis.

Results: Of the evaluated subjects, 18 were diagnosed with PA, 22 subjects did not have PA, and 1 subject was indeterminate. The mean hair weight was 33.0±13.7mg. For hair samples weighing greater than 10mg, hair weight was not correlated with hair aldosterone concentration (p=0.40). There was no difference in measured hair aldosterone between the subjects with and without PA (2.01±1.09 vs. 2.52±2.45 pg/mg; p=0.82). Among all subjects, hair aldosterone did not correlate with serum aldosterone (p=0.92), aldosterone-to-renin ratio (ARR; p=0.94), 24 hour urine aldosterone (Ualdo; p=0.85), or the serum aldosterone at the 4 hour time point of a SST (4hrAldo; p=0.98). Serum aldosterone, ARR, Ualdo, and 4hrAldo all correlated highly amongst each other (all p’s<0.001).

Conclusions: Hair aldosterone levels do not correlate with other markers of PA. Further work is needed to understand whether optimization of study conditions could improve the usefulness of hair aldosterone measurements in the evaluation of PA.

Inhibin A as a tumor marker for primary bilateral macronodular adrenal hyperplasia

SUMMARY

Primary bilateral macronodular adrenal hyperplasia (PBMAH) is a rare cause of ACTH-independent Cushing syndrome (CS). This condition is characterized by glucocorticoid and/or mineralocorticoid excess, and is commonly regulated by aberrant G-protein coupled receptor expression may be subclinical, allowing the disease to progress for years undetected. Inhibin A is a glycoprotein hormone and tumor marker produced by certain endocrine glands including the adrenal cortex, which has not been previously investigated as a potential tumor marker for PBMAH. In the present report, serum inhibin A levels were evaluated in three patients with PBMAH before and after adrenalectomy. In all cases, serum inhibin A was elevated preoperatively and subsequently fell within the normal range after adrenalectomy. Additionally, adrenal tissues stained positive for inhibin A. We conclude that serum inhibin A levels may be a potential tumor marker for PBMAH.

LEARNING POINTS

PBMAH is a rare cause of CS. PBMAH may have an insidious presentation, allowing the disease to progress for years prior to diagnosis. Inhibin A is a heterodimeric glycoprotein hormone expressed in the gonads and adrenal cortex. Inhibin A serum concentrations are elevated in some patients with PBMAH, suggesting the potential use of this hormone as a tumor marker. Further exploration of serum inhibin A concentration, as it relates to PBMAH disease progression, is warranted to determine if this hormone could serve as an early detection marker and/or predictor of successful surgical treatment.

Mosaicism for KCNJ5 Causing Early-Onset Primary Aldosteronism due to Bilateral Adrenocortical Hyperplasia

BACKGROUND

Somatic variants in KCNJ5 are the most common cause of primary aldosteronism (PA). There are few patients with PA in whom the disease is caused by germline variants in the KCNJ5 potassium channel gene (familial hyperaldosteronism type III-FH-III).

METHODS

A 5-year-old patient who developed hypertension due to bilateral adrenocortical hyperplasia (BAH) causing PA had negative peripheral DNA testing for any known genetic causes of PA. He was treated medically with adequate control of his PA but by the third decade of his life, due to worsening renal function, he underwent bilateral adrenalectomy.

RESULTS

Focused exome sequencing in multiple nodules of his BAH uncovered a "hot-spot" pathogenic KCNJ5 variant, while repeated Sanger sequencing showed no detectable DNA defects in peripheral blood and other tissues. However, whole exome, "deep" sequencing revealed that 0.23% of copies of germline DNA did in fact carry the same KCNJ5 variant that was present in the adrenocortical nodules, suggesting low level germline mosaicism for this PA-causing KCNJ5 defect.

CONCLUSIONS

Thus, this patient represents a unique case of BAH due to a mosaic KCNJ5 defect. Undoubtedly, his milder PA compared with other known cases of FH-III, was due to his mosaicism. This case has a number of implications for the prognosis, treatment, and counseling of the many patients with PA due to BAH that are seen in hypertension clinics.

SUN-356 The Effects of Selective Serotonin Reuptake Inhibitors on Urinary Free Cortisol in Patients with Carney Complex and Primary Pigmented Nodular Adrenocortical Disease

PPNAD is a rare cause of ACTH-independent Cushing syndrome mainly associated with Carney complex (CNC). It is diagnosed by histologic examination or a 6-day Liddle test (LT) showing a paradoxical increase of >50% in 24-h urinary free cortisol (UFC) on the 2^nd day of high-dose dexamethasone administration (Day 6 [D6]). PPNAD tissue has neuroendocrine features and can overexpress the serotonin (5-HT) synthesizing enzyme tryptophan hydroxylase type 2 and the 5-HT receptors types 4, 6, and 7, with formation of an illicit stimulatory serotonergic loop whose pharmacological inhibition in vitro decreases cortisol production [1]. SSRIs inhibit the reuptake of 5-HT and are used as 1^st-line antidepressants. This is a retrospective cohort study of patients with CNC and PPNAD that underwent a LT with the objective to evaluate the effect of SSRIs on UFCs in these patients. Of the 34 patients (4-65 y) with CNC and PPNAD that had a LT at our institution between 2004 and 2018, 4 patients took an SSRI during testing. No statistically significant differences were demonstrated between the SSRI (S) group and the non-SSRI (NS) group in baseline UFCs and urine 17-hydroxycorticosteroids (17OHS) and the percent increase in UFC and 17OHS on D6. Specifically, the median (IQR) baseline UFC in the S group was 36 (13-252) mcg/24h (nl 4-56) vs 35 (13-98) mcg/24h in the NS group (P=0.95). Baseline 17OHS were 11 (8-18) mg/mg creatinine (Cr) (nl ≤6) in the S group vs 8 (5-11) mg/mgCr in the NS group (P=0.27). The percent change in UFC was 208 (93-683)% in the S group and 185 (28-364)% in the NS group (P=0.89), while the percent change in 17OHS was 56 (40-87)% in the S group and 67 (16-92)% in the NS group (P=0.91). On D6, the S group appeared to have higher UFC [118 (63-635) mcg/24h vs 112 (58-201) mcg/24h; P=0.64] and 17OHS [16 (10-39) mg/mgCr vs 13 (7-17) mg/mgCr; P=0.25] than the NS group, but these were not statistically significant. Though these data do not confirm an effect of SSRIs on UFC and ultimately cortisol production in PPNAD, and the percent change in UFC during the LT was similar between both groups, the higher D6 UFC in the S group, when the baseline UFCs between the 2 groups were similar may suggest a degree of increased cortisol production in the S group. The data are limited by the small number of patients in the S group (n=4). In addition, 50% of patients in the S group vs 77% in the NS group underwent adrenalectomy, which is indicative of more severe disease in the NS group. More data are needed from this cohort to determine if SSRI use affects cortisol production in vivo, as this may have significant diagnostic and therapeutic implications for patients with CNC and PPNAD. Reference: 1. Bram, Z., et al., PKA regulatory subunit 1A inactivating mutation induces serotonin signaling in primary pigmented nodular adrenal disease. JCI Insight, 2016. 1(15): p. e87958.

MON-321 Metastatic Melanoma with Unknown Primary Site in a Patient with Multiple Endocrine Neoplasia Type 1

Background: MEN1 is a rare hereditary tumor syndrome caused by germline inactivating mutations of the tumor suppressor gene MEN1 and is characterized by a predisposition to endocrine tumors primarily of parathyroid, enteropancreatic, and anterior pituitary origin, as well as nonendocrine neoplasms. Cutaneous manifestations mainly include lipomas, angiofibromas, and collagenomas. Melanoma has been observed in MEN1 with 9 cases described in the literature, including 2 cases with unknown primary site (Nord et al. 2000; Baldauf et al. 2009; Brown et al. 2015). Clinical Case: A 45 year old man with MEN1 syndrome manifesting as primary hyperparathyroidism, metastatic pancreatic neuroendocrine tumor (NET), Zollinger-Ellison syndrome, nonfunctional pituitary microadenoma, anterior mediastinal mass and skin angiofibromas presented with a left neck mass that developed over 1 year. CT neck confirmed a 2.2 cm left lateral neck level V mass. Further evaluation revealed stable NET disease with the exception of an enlarging 1.3 cm anterior mediastinal nodule. ¹⁸F-FDG PET/CT demonstrated more activity in the left neck mass and mediastinal mass than ⁶⁸Ga-DOTATATE PET/CT. Biopsy of the left neck mass revealed a high grade malignant neoplasm with epithelioid features and markedly elevated MIB1. Tumor cells were positive for CD56, SOX-10 and S-100 protein, but negative for CD20, CD3, CD5, chromogranin, synaptophysin, AE1/AE3, CAM5.2, C-Kit and p53. Molecular analysis showed pathogenic variants in BRAF, TERT, PIK3C, and RB1, a likely pathogenic variant in FBXW7, and a variant of uncertain significance in PMS2. Given these histologic and molecular findings, the diagnosis of metastatic melanoma was favored. Ophthalmological evaluation, skin examination and biopsy of suspicious cutaneous lesions did not reveal the primary site of melanoma. PCR did not reveal MEN1 loss of heterozygosity (LOH) of the neck mass, though there was insufficient material to evaluate for large MEN1 deletions. Conclusion: Of the 9 cases of melanoma previously reported in MEN1, only 1 was evaluated for MEN1 LOH, which was not demonstrated. MEN1 LOH has been described in sporadic melanoma and in vitro and in vivo studies in mice suggest a role for MEN1 as a tumor suppressor gene in melanoma (Gao et al. 2011, Fang et al. 2013). Whether melanoma in MEN1 is related to the germline MEN1 mutation or is sporadic is still unclear. Evaluation of melanomas for MEN1 LOH initially with targeted sequencing of the germline mutation followed by LOH for markers in and near the MEN1 gene at 11q13, may help further elucidate the role of MEN1 in melanoma.