SUN-373 Small Adrenal Incidentaloma Stable in Size Becoming a Stage IV Adrenocortical Carcinoma 10 Years Later in a Young Patient Carrying a Germline APC Variant of Uncertain Significance (VUS)

Recent guidelines on adrenal incidentalomas suggested that patients with an indeterminate adrenal mass on imaging choosing not to undergo adrenalectomy to repeat imaging with either unenhanced computed tomography (CT) or Magnetic resonance imaging with chemical shift analysis in 6 to 12 months. If the adrenal mass is non-functioning and stable in size, patients may not require any additional monitoring.We report here a case of a young woman known for a small adrenal mass, stable in size for 4 years who was ultimately diagnosed with a Stage IV adrenal cortical carcinoma (ACC) 10 years later. Case report. In 2006, a 32-year-old French Canadian woman was referred in endocrinology for evaluation of a left 2.7 x 2.0 cm incidentally discovered adrenal mass. On presentation, her hormonal work up included a normal 1mg overnight dexamethasone suppression test (DST) and dehydroepiandrosterone sulfate (DHEA-S) within normal limits. On unenhanced computed tomography (CT), the radiodensity of the adrenal mass was 23 Hounsfield units (HU). The patient was followed with adrenal imaging and hormonal investigation yearly for 4 years and the adrenal mass demonstrated no growth in 4 years. Ten years after initial presentation, in 2016, after five years lost to follow up the patient presented with renal colic. Urological CT has unexpectedly revealed that the left adrenal mass had significantly progressed measuring 9 x 8.2 cm and 2 new hepatic lesions were identified. Biochemical work up demonstrated hypercortisolism and hyperandrogenemia: plasma cortisol after 1 mg overnight DST was 486 nmol/L and DHEA-S was 14.0 mmol/L (N 0.9-6.5). Twenty-four-hour urine steroid profiling was consistent with an ACC co-secreting cortisol, androgens and glucocorticoid precursors. The diagnosis of ACC with hepatic ACC metastases was confirmed by histology. Following genetic analysis, germline heterozygous variant of uncertain significance (VUS) was identified in the exon 16 of the APC gene NM_000038.5:c.2414G>A,(p.Arg805Gln) (rs200593940). The patient had no clinical manifestations of familial adenomatous polyposis. Immunohistochemical staining of the ACC were positive for IGF-2 and cytoplasmic/nuclear β-catenin, however, no somatic APC or beta-catenin mutations were found. This case illustrates that 1) small adrenal incidentaloma stable in size may progress to ACC 2) better genetic characterization of these patients may eventually give clues to this unusual evolution.

SAT-063 Peripheral Aldosterone Values During Simultaneous Bilateral Adrenal Veins Sampling (AVS) to Predict the Source of Aldosterone Secretion in Primary Aldosteronism (PA)

Background: AVS identifies aldosterone source in PA from unilateral aldosterone-producing adenoma (APA) or bilateral adrenal hyperplasia (BAH). APA and BAH can overexpress ACTH receptors, but their variable levels may explain discordant lateralization results between basal and post ACTH values (1,2). Previous studies suggested that differential response of plasma aldosterone concentration (PAC) to ACTH stimulation could predict the subtypes of PA (3). Objective: Assess the usefulness of peripheral (P) vein PAC response to ACTH to differentiate the source of excess aldosterone in patients with PA. Methods: In 215 bilaterally selective simultaneous AVS, PAC and plasma cortisol (C) were measured basally (-5 , 0 min,) and 5, 10, 15 min following ACTH 250 mcg IV bolus in adrenal and P veins; samples were also measured in P at 30, 45 and 60 min. Patients were assigned to four different lateralization ratio (LR) groups: group 1 (n= 140) lateralized source (basal LR ≥ 2 and post-ACTH LR ≥ 4), group 2 (n= 38) basal lateralization only (basal LR ≥ 2 and post-ACTH < 4), group 3 (n=10) post ACTH lateralization only (basal LR < 2 and post-ACTH ≥ 4) and group 4 (n= 27) bilateral source (basal LR < 2 and post-ACTH < 4. The P vein parameters included: mean basal PAC, maximal PAC (PAC_max) and maximal PAC/C ratio (PAC_max/C) following ACTH bolus, PAC absolute increase, PAC relative increase, maximal absolute variation of PAC/C ratio between post-ACTH and basal measures. Results: Mean basal PAC in P was significantly higher in group 1 than in group 2 or 4 (p < 0.001). PAC_max, PAC_max/C and PAC absolute increase following ACTH bolus were higher in group 1 than the others (p < 0.017). Group 4 had higher PAC relative increase following ACTH bolus than group 1 (p: 0.0097). ROC curves analysis for these parameters were performed by comparing group 1 with the others. Best AUC were obtained with mean basal PAC (AUC: 0.7386 95% IC: 0.67-0.81), PAC_max (AUC: 0.7386 95% IC: 0.67-0.81) and PAC_max/C (AUC: 0.7546 95% IC: 0.68-0.82). A mean basal P vein PAC of 678 pmol/L provides a specificity of 91% and a sensitivity of 41%, PAC_max/C of 3.63 provides a specificity of 91% and a sensitivity of 43%, while a PACmax of 2128 pmol/L provides a specificity of 91% and a sensitivity of 47% to exclude cases of bilateral disease. Conclusion: P mean basal PAC and PAC_max and PAC_max/C following ACTH are higher in basal and ACTH lateralized PA than in the other groups. BAH patients have a higher relative increase in P PAC than basal and post-ACTH lateralized PA. The selected P PAC cutoff values fail to adequately distinguish all groups and cannot replace the requirement to conduct AVS. References: (1) El Ghorayeb et al., J Clin Endocrinol Metab. 2018;101:1826-1835. (2) Zwermann et al., Eur J Endocrinol. 2009;160 (3):443-451 (3) Jiang et al., J Clin Endocrinol Metab. 2015;100(5):1837–44.

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

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

CT Characteristics of Pheochromocytoma: Relevance for the Evaluation of Adrenal Incidentaloma

Background

Up to 7% of all adrenal incidentalomas (AIs) are pheochromocytomas (PCCs). In the evaluation of AI, it is generally recommended that PCC be excluded by measurement of plasma-free or 24-hour urinary fractionated metanephrines. However, recent studies suggest that biochemical exclusion of PCC not be performed for lesions with CT characteristics of an adrenocortical adenoma (ACA).

Aim

To determine the proportion of PCCs with ACA-like attenuation or contrast washout on CT.

Methods

For this multicenter retrospective study, two central investigators independently analyzed the CT reports of 533 patients with 548 histologically confirmed PCCs. Data on tumor size, unenhanced Hounsfield units (HU), absolute percentage washout (APW), and relative percentage washout (RPW) were collected in addition to clinical parameters.

Results

Among the 376 PCCs for which unenhanced attenuation data were available, 374 had an attenuation of >10 HU (99.5%). In the two exceptions (0.5%), unenhanced attenuation was exactly 10 HU, which lies just within the range of ≤10 HU that would suggest a diagnosis of ACA. Of 76 PCCs with unenhanced HU > 10 and available washout data, 22 (28.9%) had a high APW and/or RPW, suggestive of ACA.

Conclusion

Based on the lack of PCCs with an unenhanced attenuation of <10 HU and the low proportion (0.5%) of PCCs with an attenuation of 10 HU, it seems reasonable to abstain from biochemical testing for PCC in AIs with an unenhanced attenuation of ≤10 HU. The assessment of contrast washout, however, is unreliable for ruling out PCC.

Coexistence of Myelolipoma and Primary Bilateral Macronodular Adrenal Hyperplasia With GIP-Dependent Cushing's Syndrome

Introduction: Adrenal myelolipomas are usually isolated benign adrenal lesions, but can be adjacent to steroid-secreting adrenocortical tumors. We studied the aberrant regulation of cortisol secretion in a 61 year-old woman with combined bilateral myelolipomas and primary bilateral macronodular adrenal hyperplasia (BMAH) causing Cushing's syndrome. Materials and Methods: Cortisol response was measured during in vivo tests that transiently modulated the levels of ligands for potential aberrant receptors, including GIP. Response to medical therapies decreasing GIP was monitored. Expression of ACTH and of GIP receptors were examined in resected adrenal tissues by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). Results: In vivo, cortisol increased in response to mixed meals (+353%), oral 75 g glucose (+71%), GIP infusion (+416%), and hLH IV (+243%). Suppression of GIP by pasireotide improved cortisol secretion but produced hyperglycemia. The left adrenal was predominantly composed of myelolipoma and strands of BMAH, while the right was mainly composed of BMAH with some foci of myelolipoma on pathology. No ACTH was detectable by immunohistochemistry in BMAH or myelolipomas tissue. Ectopic GIP receptor was confirmed by RT-PCR and immunohistochemistry in BMAH tissues but not in the myelolipomas. No germline mutations were identified in the ARMC5 gene of the patient's leucocyte DNA. Conclusion: This is the first report of interspersed myelolipoma and BMAH with GIP-dependent Cushing's syndrome. In contrast with the BMAH tissues, myelolipoma tissue did not express specific GIP receptors. The potential mechanisms responsible for the interspersed growth of those two lesions remain to be identified.

Isolated Pheochromocytoma in a 73-Year-Old Man With No Clinical Manifestations of Type 1 Neurofibromatosis Carrying an Unsuspected Deletion of the Entire NF1 Gene

Pheochromocytomas (PHEOs) are a rare cause of endocrine hypertension that requires genetic counseling since at least 30% of PHEOs are associated with a germline mutation in a susceptibility gene. Neurofibromatosis type 1, NF1 is amongst the 16 known causing genes for pheochromocytomas/paragangliomas. We report a case of a 73-year-old man with PHEO in whom genetic testing revealed a large pathogenic heterozygous deletion of 1.14 Mb encompassing the entire coding sequence of the NF1 gene while the patient showed no signs of clinical NF1.This case illustrates that the diagnosis of NF1 should not be excluded in patients with PHEO in the absence of clinical diagnosis of the disease and support that older patients with PHEO should also be offered genetic counseling.

Genetic Characterization of GnRH/LH-Responsive Primary Aldosteronism

BACKGROUND

Recently, somatic β-catenin mutations (CTNNB1) identified in aldosterone-producing adenomas (APAs) from three women were suggested to be responsible for the aberrant overexpression of luteinizing hormone/choriogonadotropin receptor and gonadotropin-releasing hormone receptor in the APA.

OBJECTIVE

To genetically characterize patients with primary aldosteronism (PA) evaluated in vivo for gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH)-responsive aldosterone secretion.

METHOD

Patients with PA were evaluated in vivo to determine the possible regulation of aldosterone secretion by GnRH or LH. Genetic analysis of the CTNNB1, KCNJ5, ATP1A1, ATP2B3, CACNA1D, and GNAS genes were performed in this cohort and a control cohort of PA not tested in vivo for GnRH response.

RESULTS

We studied 50 patients with confirmed PA, including 36 APAs, 12 bilateral macronodular adrenal hyperplasias, 1 oncocytoma, and 1 bilateral hyperplasia with cosecretion of cortisol. Among 23 patients tested in vivo for GnRH response of aldosterone, 7 (30.4%) had a positive response, 4 (17.4%) a partial response, and 12 (52.2%) no response. No somatic CTNNB1 mutations were identified, but the disease-causing c.451G>C KCNJ5 mutation was found in two individuals with partial and no GnRH responses and an individual showing a positive response to LH. Two additional somatic pathogenic mutations, CACNA1D c.776T>A and ATP1A1 c.311T>G, were identified in two patients with no GnRH responses. In the 26 patients not tested for GnRH response, we identified 2 CTNNB1 (7.7%), 13 KCNJ5 (50%), and 1 CACNA1D (3.8%) mutations.

CONCLUSION

Aberrant regulation of aldosterone by GnRH is frequent in PA, but is not often associated with somatic CTNNB1, although it may be found with somatic KCNJ5 mutations.

MANAGEMENT OF ENDOCRINE DISEASE: Differential diagnosis, investigation and therapy of bilateral adrenal incidentalomas

The investigation and management of unilateral adrenal incidentalomas have been extensively considered in the last decades. While bilateral adrenal incidentalomas represent about 15% of adrenal incidentalomas (AIs), they have been less frequently discussed. The differential diagnosis of bilateral incidentalomas includes metastasis, primary bilateral macronodular adrenal hyperplasia and bilateral cortical adenomas. Less frequent etiologies are bilateral pheochromocytomas, congenital adrenal hyperplasia (CAH), Cushing's disease or ectopic ACTH secretion with secondary bilateral adrenal hyperplasia, primary malignancies, myelolipomas, infections or hemorrhage. The investigation of bilateral incidentalomas includes the same hormonal evaluation to exclude excess hormone secretion as recommended in unilateral AI, but diagnosis of CAH and adrenal insufficiency should also be excluded. This review is focused on the differential diagnosis, investigation and treatment of bilateral AIs.

MECHANISMS OF ENDOCRINOLOGY: Cell cycle regulation in adrenocortical carcinoma

Adrenocortical carcinomas (ACCs) are rather rare endocrine tumors that often have a poor prognosis. The reduced survival rate associated with these tumors is due to their aggressive biological behavior, combined with the scarcity of effective treatment options that are currently available. The recent identification of the genomic alterations present in ACC have provided further molecular mechanisms to develop consistent strategies for the diagnosis, prevention of progression and treatment of advanced ACCs. Taken together, molecular and genomic advances could be leading the way to develop personalized medicine in ACCs similarly to similar developments in lung or breast cancers. In this review, we focused our attention to systematically compile and summarize the alterations in the cell cycle regulation that were described so far in ACC as they are known to play a crucial role in cell differentiation and growth. We have divided the analysis according to the major transition phases of the cell cycle, G1 to S and G2 to M. We have analyzed the most extensively studied checkpoints: the p53/Rb1 pathway, CDC2/cyclin B and topoisomerases (TOPs). We reached the conclusion that the most important alterations having a potential application in clinical practice are the ones related to p53/Rb1 and TOP 2. We also present a brief description of on-going clinical trials based on molecular alterations in ACC. The drugs have targeted the insulin-like growth factor receptor 1, TOP 2, polo-like kinase1, cyclin-dependent kinase inhibitors, p53 reactivation and CDC25.

Unusual presentation of pheochromocytoma: thirteen years of anxiety requiring psychiatric treatment

Pheochromocytoma is a rare tumor of the adrenal gland. It often presents with the classic triad of headache, palpitations and generalized sweating. Although not described as a typical symptom of pheochromocytoma, anxiety is the fourth most common symptom reported by patients suffering of pheochromocytoma. We report the case of a 64 year old man who had severe anxiety and panic disorder as presenting symptoms of pheochromocytoma. After 13 years of psychiatric follow-up, the patient was diagnosed with malignant pheochromocytoma. After surgical resection of his pheochromocytoma and his hepatic metastases, the major panic attacks completely disappeared, the anxiety symptoms improved significantly and the psychiatric medications were stopped except for a very low maintenance dose of venlafaxine. We found in our cohort of 160 patients with pheochromocytoma 2 others cases of apparently benign tumors with severe anxiety that resolved after pheochromocytoma resection. These cases highlight that pheochromocytoma should be included in the differential diagnosis of refractory anxiety disorder.

Learning points

Anxiety and panic disorder may be the main presenting symptoms of pheochromocytoma.The diagnosis of pheochromocytoma should be excluded in cases of long-term panic disorder refractory to medications since the anxiety may be secondary to a catecholamine-secreting tumor.Surgical treatment of pheochromocytoma leads to significant improvement of anxiety disorders.

Aberrant G-protein coupled hormone receptor in adrenal diseases

The regulation of cortisol or aldosterone production when ACTH of pituitary origin or the renin-angiotensin systems are suppressed in primary adrenal Cushing's syndrome or in primary aldosteronism is exerted by diverse genetic and molecular mechanisms. In addition to recently identified mutations in various genes implicated in the cyclic AMP or ion channel pathways, steroidogenesis is not really autonomous as it is frequently regulated by the aberrant adrenocortical expression of diverse hormone receptors, particularly G-protein coupled hormone receptors (GPCR) which can substitute for the normal function of ACTH or angiotensin-II. In addition, paracrine or autocrine production of ligands for the aberrant GPCR such as ACTH or serotonin is found in some adrenal tumors or hyperplasias and participates in a complex regulatory loop causing steroid excess. Targeted therapies to block the aberrant ligands or their receptors could become useful in the future, particularly for patients with bilateral source of steroid excess.

Adrenal GIPR expression and chromosome 19q13 microduplications in GIP-dependent Cushing's syndrome

GIP-dependent Cushing's syndrome is caused by ectopic expression of glucose-dependent insulinotropic polypeptide receptor (GIPR) in cortisol-producing adrenal adenomas or in bilateral macronodular adrenal hyperplasias. Molecular mechanisms leading to ectopic GIPR expression in adrenal tissue are not known. Here we performed molecular analyses on adrenocortical adenomas and bilateral macronodular adrenal hyperplasias obtained from 14 patients with GIP-dependent adrenal Cushing's syndrome and one patient with GIP-dependent aldosteronism. GIPR expression in all adenoma and hyperplasia samples occurred through transcriptional activation of a single allele of the GIPR gene. While no abnormality was detected in proximal GIPR promoter methylation, we identified somatic duplications in chromosome region 19q13.32 containing the GIPR locus in the adrenocortical lesions derived from 3 patients. In 2 adenoma samples, the duplicated 19q13.32 region was rearranged with other chromosome regions, whereas a single tissue sample with hyperplasia had a 19q duplication only. We demonstrated that juxtaposition with cis-acting regulatory sequences such as glucocorticoid response elements in the newly identified genomic environment drives abnormal expression of the translocated GIPR allele in adenoma cells. Altogether, our results provide insight into the molecular pathogenesis of GIP-dependent Cushing's syndrome, occurring through monoallelic transcriptional activation of GIPR driven in some adrenal lesions by structural variations.

Pheochromocytomas are diagnosed incidentally and at older age in neurofibromatosis type 1

INTRODUCTION

Guidelines do not currently recommend routine systematic hormonal screening for pheochromocytoma (PHEO) in all/normotensive patients with neurofibromatosis type 1 (NF1), in contrast to other PHEO-predisposing genetic syndromes such as Von Hippel-Lindau syndrome and multiple endocrine neoplasia type 2.

OBJECTIVES

To characterize and compare parameters of PHEO in patients with NF1 to patients with or without other germline mutations.

METHODS

A retrospective chart review of patients with histologically proven PHEO at the Centre hospitalier de l'Université de Montréal from 2000 through 2015.

RESULTS

Neurofibromatosis type 1 was diagnosed clinically in nine patients in our cohort of 145 PHEO (6·2%). The mean age at diagnosis was 48 ± 14 years, and seven patients had hypertension. No PHEO was diagnosed by systematic clinical screening. The mode of presentation was adrenal incidentalomas in five patients. Urinary metanephrines were elevated in 5/9 cases. Mean tumour diameter was 3·5 cm (min-max 1·5-12·5 cm). One had bilateral PHEO and none were malignant to date. Statistically significant differences were noted when comparing PHEO in NF1 to other genetic syndromes (n = 20), in terms of age at diagnosis (mean 48 vs 30 years P < 0·05), initial mode of presentation (no PHEO detected by routine screening in NF1 vs 40% in other genetic syndromes P < 0·05) and familial history of catecholamine-secreting tumour (none in NF1 vs 55% in patients with other genetic syndrome P < 0·05).

CONCLUSIONS

Pheochromocytoma in NF1 occurs in older patients with no family history compared to other syndromes; it is mostly unilateral, secretory and benign. The older age at diagnosis of PHEO could be secondary to delay in identification due to lack of systematic screening for PHEO in NF1.

Adrenal vein sampling in primary aldosteronism: concordance of simultaneous vs sequential sampling

OBJECTIVE

Many investigators believe that basal adrenal venous sampling (AVS) should be done simultaneously, whereas others opt for sequential AVS for simplicity and reduced cost. This study aimed to evaluate the concordance of sequential and simultaneous AVS methods.

DESIGN AND METHODS

Between 1989 and 2015, bilateral simultaneous sets of basal AVS were obtained twice within 5 min, in 188 consecutive patients (59 women and 129 men; mean age: 53.4 years). Selectivity was defined by adrenal-to-peripheral cortisol ratio ≥2, and lateralization was defined as an adrenal aldosterone-to-cortisol ratio ≥2, the contralateral side. Sequential AVS was simulated using right sampling at -5 min (t = -5) and left sampling at 0 min (t = 0).

RESULTS

There was no significant difference in mean selectivity ratio (P = 0.12 and P = 0.42 for the right and left sides respectively) and in mean lateralization ratio (P = 0.93) between t = -5 and t = 0. Kappa for selectivity between 2 simultaneous AVS was 0.71 (95% CI: 0.60-0.82), whereas it was 0.84 (95% CI: 0.76-0.92) and 0.85 (95% CI: 0.77-0.93) between sequential and simultaneous AVS at respectively -5 min and at 0 min. Kappa for lateralization between 2 simultaneous AVS was 0.84 (95% CI: 0.75-0.93), whereas it was 0.86 (95% CI: 0.78-0.94) and 0.80 (95% CI: 0.71-0.90) between sequential AVS and simultaneous AVS at respectively -5 min at 0 min.

CONCLUSIONS

Concordance between simultaneous and sequential AVS was not different than that between 2 repeated simultaneous AVS in the same patient. Therefore, a better diagnostic performance is not a good argument to select the AVS method.

A SDHC Founder Mutation Causes Paragangliomas (PGLs) in the French Canadians: New Insights on the SDHC-Related PGL

BACKGROUND

More than 40% of patients with paragangliomas (PGLs) harbor a germline mutation of the known PGL susceptibility genes, mainly in the SDHB or SDHD genes.

OBJECTIVE

The objective of the study was to characterize the genetic background of the French Canadian (FC) patients with PGLs and provide new clinical and paraclinical insights on SDHC-related PGLs.

METHODS

Genetic testing has been offered to FC patients affected with PGLs followed up at the adrenal genetics clinic at Centre hospitalier de l'Université de Montréal. After genetic counseling, 29 FC patients consented for PGL genetic testing.

RESULTS

Thirteen of 29 patients (44.8%) carried a germline mutation. The same heterozygous nonsense mutation at codon 133 of exon 5 of the SDHC gene (c.397C>T, p.[Arg133Ter]) was found in nine patients, representing 69.2% of the patients having a germline mutation. Seventy percent of these patients had head and neck PGLs. Twenty percent had multiple and 30% had malignant PGLs. We traced back the ascending genealogy of 10 index cases (nine patients from our cohort and one patient referred to us) and found that this mutation was most probably introduced in Nouvelle France by a couple of French settlers who established themselves in the 17th century.

CONCLUSIONS

We found that 31% of the PGLs in the French Canadian can be explained by the SDHC mutation (c.397C>T, p.[Arg133Ter]). The dominance of the SDHC mutation is unique to the FCs and is most likely due to a French founder effect. SDHC gene analysis should be prioritized in FC patients with PGL.

First case report of an adrenocortical carcinoma caused by a BRCA2 mutation

BACKGROUND

Adrenocortical carcinoma (ACC) may rarely be a component of inherited cancer syndromes such as Li-Fraumeni syndrome and Beckwith-Wiedemann syndrome. ACC caused by a BRCA2 mutation has never been reported.

METHODS

Nucleotide sequencing of BRCA2 in lymphocyte and tumoral DNA of a 50-year-old male who presented with an androgen-secreting ACC and a strong family history of breast, ovarian, and pancreatic cancers.

RESULTS

A germline BRCA2 2 bp heterozygous deletion at nucleotide 8765 (8765delAG) leading to a frameshift mutation (p.Glu2846GlyfsX23) was detected. Only the BRCA2 deleted allele was retained in the ACC tumoral DNA compared with the control DNA supporting a loss of heterozygosity in the tumor.

CONCLUSION

This is the first reported case of a patient with ACC associated with a BRCA2 germline mutation. Loss of heterozygosity in ACC DNA suggests a causal link with the BRCA2 8765delAG mutation.

Basal and Post-ACTH Aldosterone and Its Ratios Are Useful During Adrenal Vein Sampling in Primary Aldosteronism

CONTEXT

Adrenal vein sampling (AVS) is required to identify a lateralized or bilateral aldosterone source in primary aldosteronism.

OBJECTIVES

Our objectives were to compare basal and post-ACTH selectivity ratio (SR) and lateralization ratio (LR) and to determine the prevalence of basal contralateral suppression and its effect on surgical outcome.

PATIENTS AND INTERVENTION

Bilateral simultaneous adrenal vein samples were obtained before and after a 250-μg bolus of ACTH. Analyses were conducted on 171 technically successful AVS and on the subgroup of 66 operated patients with evaluable outcome data.

RESULTS

ACTH increased selectivity on both sides from 66.7% in basal samples (SR ≥ 2) to 91.8% poststimulation (SR ≥ 5). A discordance of lateralization between basal (LR ≥ 2) and post-ACTH (LR ≥ 4) values was observed in 28% of cases, which were mostly lateralized cases basally that became bilateral post-ACTH. Basal CL suppression is present in only 30% using absolute ratio of aldosterone between the opposite (nondominant) adrenal vein and the peripheral vein AOPP/AP below 1.5 vs in 77% using aldosterone/cortisol ratio (A/C)OPP/(A/C)P below 1.5. The absence of CL suppression was associated with a lower rate of response to adrenalectomy in terms of clinical and biochemical parameters with difference in clinical cure (55% vs 13% P = .0003) and overall cure (35% vs 9%, P = .0084) using AOPP/AP, but not when using (A/C)OPP/(A/C)P.

CONCLUSIONS

Stimulation with ACTH is useful to improve selectivity of AVS but can frequently modify interpretation of lateralization. Basal ratios are as important as post-ACTH ratios to set an indication of adrenalectomy. AOPP/AP is superior to (A/C)OPP/(A/C)P to assess contralateral suppression. Infrequent CL suppression reveals frequent occurrence of contralateral hyperplasia in lateralized cases and helps predict postoperative outcomes.

Long-term cognitive effects of glucocorticoid excess in Cushing's syndrome

CONTEXT AND OBJECTIVE

We previously found that patients with Cushing's syndrome (CS) scored lower than controls in several domains of cognitive function and that correction of hypercortisolism is not necessarily correlated with short-term improvement in intellectual performance. Here, we examined the long-term outcome in patients treated for CS by assessing the extent to which the detrimental effects of glucocorticoid (GC) excess on cognition can be reversed three years after corrective surgery.

DESIGN

A battery of neuropsychological tests, including tests of attention, visuospatial processing, learning and memory, and executive functioning were administered pre-treatment and 12, 24 and 36 months post-treatment.

PATIENTS AND CONTROL SUBJECTS

We included 18 patients with endogenous CS recruited before surgical treatment and 18 controls matched for age, sex and education.

RESULTS

CS patients performed worse than controls on tests of attention, executive functioning and nonverbal aspects of memory. Moreover, at 36 months following eucortisolism, executive function performance and, to a lesser extent, attention tasks showed limited change compared to pre-treatment testing.

CONCLUSION

Chronic hypercortisolism is accompanied by a deleterious impact on aspects of cognitive function. This negative effect on attention, executive performance and nonverbal memory seen in patients with CS suggests a differential effect of excess GCs upon different brain areas and networks. This influence persists years after the return to normal cortisol secretion levels.

Rapid and Complete Remission of Metastatic Adrenocortical Carcinoma Persisting 10 Years After Treatment With Mitotane Monotherapy: Case Report and Review of the Literature

Mitotane has been used for more than 5 decades as therapy for adrenocortical carcinoma (ACC). However its mechanism of action and the extent of tumor response remain incompletely understood. To date no cases of rapid and complete remission of metastatic ACC with mitotane monotherapy has been reported. A 52-year-old French Canadian man presented with metastatic disease 2 years following a right adrenalectomy for stage III nonsecreting ACC. He was started on mitotane which was well tolerated despite rapid escalation of the dose. The patient course was exceptional as he responded to mitotane monotherapy after only few months of treatment. Initiation of chemotherapy was not needed and he remained disease-free with good quality of life on low maintenance dose of mitotane during the following 10 years. A germline heterozygous TP53 exon 4 polymorphism c.215C>G (p. Pro72Arg) was found. Immunohistochemical stainings for IGF-2 and cytoplasmic β-catenin were positive. Advanced ACC is an aggressive disease with poor prognosis and the current therapeutic options remain limited. These findings suggest that mitotane is a good option for the treatment of metastatic ACC and might result in rapid complete remission in selected patients.

Role of ACTH and Other Hormones in the Regulation of Aldosterone Production in Primary Aldosteronism

The major physiological regulators of aldosterone production from the adrenal zona glomerulosa are potassium and angiotensin II; other acute regulators include adrenocorticotropic hormone (ACTH) and serotonin. Their interactions with G-protein coupled hormone receptors activate cAMP/PKA pathway thereby regulating intracellular calcium flux and CYP11B2 transcription, which is the specific steroidogenic enzyme of aldosterone synthesis. In primary aldosteronism (PA), the increased production of aldosterone and resultant relative hypervolemia inhibits the renin and angiotensin system; aldosterone secretion is mostly independent from the suppressed renin-angiotensin system, but is not autonomous, as it is regulated by a diversity of other ligands of various eutopic or ectopic receptors, in addition to activation of calcium flux resulting from mutations of various ion channels. Among the abnormalities in various hormone receptors, an overexpression of the melanocortin type 2 receptor (MC2R) could be responsible for aldosterone hypersecretion in aldosteronomas. An exaggerated increase in plasma aldosterone concentration (PAC) is found in patients with PA secondary either to unilateral aldosteronomas or bilateral adrenal hyperplasia (BAH) following acute ACTH administration compared to normal individuals. A diurnal increase in PAC in early morning and its suppression by dexamethasone confirms the increased role of endogenous ACTH as an important aldosterone secretagogue in PA. Screening using a combination of dexamethasone and fludrocortisone test reveals a higher prevalence of PA in hypertensive populations compared to the aldosterone to renin ratio. The variable level of MC2R overexpression in each aldosteronomas or in the adjacent zona glomerulosa hyperplasia may explain the inconsistent results of adrenal vein sampling between basal levels and post ACTH administration in the determination of source of aldosterone excess. In the rare cases of glucocorticoid remediable aldosteronism, a chimeric CYP11B2 becomes regulated by ACTH activating its chimeric CYP11B1 promoter of aldosterone synthase in bilateral adrenal fasciculate-like hyperplasia. This review will focus on the role of ACTH on excess aldosterone secretion in PA with particular focus on the aberrant expression of MC2R in comparison with other aberrant ligands and their GPCRs in this frequent pathology.

ARMC5 mutations in a large French-Canadian family with cortisol-secreting β-adrenergic/vasopressin responsive bilateral macronodular adrenal hyperplasia

BACKGROUND

Bilateral macronodular adrenal hyperplasia (BMAH) is a rare cause of Cushing's syndrome (CS) and its familial clustering has been described previously. Recent studies identified that ARMC5 mutations occur frequently in BMAH, but the relation between ARMC5 mutation and the expression of aberrant G-protein-coupled receptor has not been examined in detail yet.

METHODS

We studied a large French-Canadian family with BMAH and sub-clinical or overt CS. Screening was performed using the 1-mg dexamethasone suppression test (DST) in 28 family members. Screening for aberrant regulation of cortisol by various hormone receptors were examined in vivo in nine individuals. Sequencing of the coding regions of ARMC5 gene was carried out.

RESULTS

Morning ambulating cortisol post 1 mg DST were >50 nmol/l in 5/8 members in generation II (57-68 years old), 9/22 in generation III (26-46 years old). Adrenal size was enlarged at different degrees. All affected patients increased cortisol following upright posture, insulin-induced hypoglycemia and/or isoproterenol infusion. β-blockers led to the reduction of cortisol secretion in all patients with the exception of two who had adrenalectomies because of β-blockers intolerance. We identified a heterozygous germline variant in the ARMC5 gene c.327_328insC, (p.Ala110Argfs*9) in nine individuals with clinical or subclinical CS, in four out of six individuals with abnormal suppression to dexamethasone at initial investigation and one out of six individuals with current normal clinical screening tests.

CONCLUSIONS

Systematic screening of members of the same family with hereditary BMAH allows the diagnosis of unsuspected subclinical CS associated with early BMAH. The relation between the causative ARMC5 mutation and the reproducible pattern of aberrant β-adrenergic and V1-vasopressin receptors identified in this family remains to be elucidated.