18F-fluorocholine PET/CT detects parathyroid gland hyperplasia as well as adenoma: 401 PET/CTs in one center.

BACKGROUND: During the past decade, 18F-fluorocholine (FCH) PET/CT has been continuously performed at Tenon Hospital (Paris, France) for the detection of hyperfunctioning parathyroid glands (PT). METHODS: A cohort of 401 patients, deliberately referred for HPT since September 2012, has been analyzed. The aim of this real-life retrospective study was to determine the diagnostic utility of FCH in this setting, overall and in subgroups according to the type of hyperparathyroidism (HPT), the context of FCH in the imaging work-up and in the patient's history: initial imaging or persistence or recurrence after previous parathyroidectomy (PTX). The influence of the histologic type of resected PTs, hyperplasia or adenoma, on the preoperatory detection on FCH PET/CT has been studied as well. RESULTS: Four hundred one FCH PET/CTs were included in the cohort, performed in 323 patients with primary HPT (pHPT), including 18 with familial HPT (fHPT), and in 78 patients with secondary renal HPT (rHPT). The overall positivity rate in the 401 FCH PET/CTs was 73%. The PTX rate was twice greater in patients whose FCH PET/CT was positive than negative (73% vs. 35%). Abnormal PT(s) were pathology proven in 214 patients: only hyperplastic gland(s) in 75 cases and at least one adenoma in 136 cases; FCH PET/CT sensitivity was 89% and 92%, respectively. Similarly, there was no significant difference in patient-based sensitivity whether FCH PET/CT was performed as 1st line or later in the imaging work-up, or indicated for initial imaging or for suspicion of persistent or recurrent HPT. Gland-based sensitivity was significantly lower for hyperplasia than for adenoma (72% and 86%, respectively). The lowest gland-based sensitivity value was 65%, observed in case of hyperplasia and when FCH was performed late in the imaging work-up. FCH PET/CT correctly showed multiglandular HPT (MGD) in 36/61 proven cases, 59%. Results of ultrasonography (US) and 99mTc-sestaMIBI (MIBI) imaging were available in 346 and 178 patients, respectively. For both modalities, the corresponding sensitivity values were significantly less than those of FCH PET/CT (e.g., overall gland-based sensitivity 78% for FCH, 45% for US, 30% for MIBI) and MGD was detected in 32% of cases by US and 15% by MIBI. CONCLUSIONS: Although FCH PET/CT has been performed since 2017 as 1st line imaging for HPT at Tenon Hospital (Paris, France), a large majority of patients underwent prior US and/or MIBI in their preoperative work-up. Therefore, a selection bias is very likely, as most patients referred to FCH PET/CT had non-conclusive or discordant results of US and MIBI, explaining the low performance of those modalities in the present cohort compared to published results. Nevertheless, the superiority of FCH PET/CT over US and MIBI in detecting abnormal PTs reported in various comparative studies is definitely confirmed in this larger real-life cohort. The detection with FCH PET/CT of hyperplastic PTs was somewhat lower than that of adenomas but was better than using US or MIBI. The present results lead to recommend FCH PET/CT as the first line imaging modality in HPT when it is widely available or, if less available, at least in HPT with predominance of hyperplasia and/or MGD.

KDM1A inactivation causes hereditary food-dependent Cushing syndrome.

PURPOSE: This study aimed to investigate the genetic cause of food-dependent Cushing syndrome (FDCS) observed in patients with primary bilateral macronodular adrenal hyperplasia (PBMAH) and adrenal ectopic expression of the glucose-dependent insulinotropic polypeptide receptor. Germline ARMC5 alterations have been reported in about 25% of PBMAH index cases but are absent in patients with FDCS. METHODS: A multiomics analysis of PBMAH tissues from 36 patients treated by adrenalectomy was performed (RNA sequencing, single-nucleotide variant array, methylome, miRNome, exome sequencing). RESULTS: The integrative analysis revealed 3 molecular groups with different clinical features, namely G1, comprising 16 patients with ARMC5 inactivating variants; G2, comprising 6 patients with FDCS with glucose-dependent insulinotropic polypeptide receptor ectopic expression; and G3, comprising 14 patients with a less severe phenotype. Exome sequencing revealed germline truncating variants of KDM1A in 5 G2 patients, constantly associated with a somatic loss of the KDM1A wild-type allele on 1p, leading to a loss of KDM1A expression both at messenger RNA and protein levels (P = 1.2 × 10-12 and P < .01, respectively). Subsequently, KDM1A pathogenic variants were identified in 4 of 4 additional index cases with FDCS. CONCLUSION: KDM1A inactivation explains about 90% of FDCS PBMAH. Genetic screening for ARMC5 and KDM1A can now be offered for most PBMAH operated patients and their families, opening the way to earlier diagnosis and improved management.

Life expectancy and likelihood of surgery in multiple endocrine neoplasia type 1: AFCE and GTE cohort study.

BACKGROUND: The overall natural history, risk of death and surgical burden of patients with multiple endocrine neoplasia type 1 (MEN1) is not well known. METHODS: Patients with MEN1 from a nationwide cohort were included. The survival of patients with MEN1 was compared with that of the general population using simulated controls. The cumulative probabilities of MEN1-specific operations and postoperative mortality were assessed, and surgical sequences were analysed using sunburst charts and Venn diagrams. RESULTS: A total of 1386 patients with MEN1 were included. Life expectancy was significantly reduced in patients with MEN1 compared with simulated controls from the general population, with a lifetime difference of 15 years. Mutations affecting the JunD interaction domain had a significant negative impact on survival. Survival for patients with MEN1 compared with the general population improved over time. The probability of experiencing at least one specific MEN1 operation was above 95 per cent after 75 years, and most patients had surgery at least twice during their lifetime. Time to a 50 per cent risk of MEN1 surgery was 30.5 years for patients born after 1960, compared with 47.9 years for those born before 1960. Sex and mutations affecting the JunD interacting domain had no impact on time to first surgery. There was considerable heterogeneity in surgical sequences, with no specific clinical pathway. CONCLUSION: Life expectancy was significantly lower among patients with MEN1 compared with the general population, and further decreased in patients with mutations affecting the JunD interacting domain. Almost all patients underwent at least one MEN1-specific operation during their lifetime, but there was no standardized sequence of surgery.

Multiple endocrine neoplasia type 1 or 4: detection of hyperfunctioning parathyroid glands with 18F-fluorocholine PET/CT. Illustrative cases and pitfalls.

18F-fluorocholine (FCH) PET/CT is now well established to detect the hyperfunctioning parathyroid glands (HFPTG) in a case of sporadic primary hyperparathyroidism (pHPT), but only limited evidence is available about the utility of FCH PET/CT to detect the HFPTG in patients with multiple endocrine neoplasia (MEN) type 1 or 4. The pHPT in this context frequently consists in a multiglandular disease with small hyperplastic glands rather than adenomas, which is challenging for imaging modalities. The data of patients with MEN1 or MEN4 after parathyroidectomy referred to FCH PET/CT for presurgical localization of HFPTG were retrospectively reviewed, including follow-up after parathyroidectomy, in search for diagnostic performance and for potential pitfalls. In the present cohort, 16 patients referred to FCH PET/CT as part of their initial pHPT work-up were subsequently operated, 44 abnormal parathyroid glands (PT) were resected, of which 32 (73%) had been detected on FCH PET/CT and 2 considered as equivocal foci. Nine patients referred to FCH PET/CT for recurrent pHPT who were subsequently operated, 14 abnormal PT were resected, all had been detected on FCH PET/CT. FCH PET/CT permitted a unilateral approach for PTx in 4 of them. In one patient with MEN4 and pHPT, the HFPTG could not be visualized on FCH PET/CT but was localized by ultrasonography. Several causes of false positive or false negative results, incidental finding and pitfalls are listed and discussed. FCH PET/CT has a positive benefit/risk ratio in the detection of HFPTG in case of MEN1 (the data in MEN4 being currently very limited) with the most effective detection rate of current imaging modalities for HFPTG, few pitfalls, and an adequate impact on patient management compared to sesta MIBI SPECT and ultrasonography.

Prolonged response to 177Lu-DOTATATE therapy of a bone marrow infiltration in a refractory thymic neuro endocrine tumor.

Thymic neuro endocrine tumor (tNET) are extremely rare malignancies with poor prognosis, requiring investigation of novel therapeutic approaches. 177Lu-DOTATATE is a successful systemic treatment modality in patients with metastatic gastroenteropancreatic but it role in tNET is not yet well established. Here we report a case of a 39-year-old man with refractory bone marrow infiltration of a tNET, treated by 4 cycles of peptide receptor radionuclide therapy (PRRT) with 177Lu DOTATATE. Since the first cycle, clinical symptoms were substantially decreased, without any severe subacute haematological toxicity. Three months after the end of PRRT, both 68Ga-DOTATOC and 18F-FDG PET confirmed a partial response, already suggested by 177Lu-DOTATATE treatment scan with a significant decrease of the bone marrow uptake between the first and fourth cycle. This report highlights that PRRT could be an effective therapeutic option for advanced bone metastatic disease tNET, with the significant benefit of alleviation of bone pain and radiologic response, without severe or irreversible haematotoxicity.

Succinate detection using in vivo 1H-MR spectroscopy identifies germline and somatic SDHx mutations in paragangliomas.

PURPOSE: Germline mutations in genes encoding succinate dehydrogenase (SDH) are frequent in patients with pheochromocytoma and paraganglioma (PPGL). They lead to SDH inactivation, mediating a massive accumulation of succinate, which constitutes a highly specific biomarker of SDHx-mutated tumors when measured in vitro. In a recent pilot study, we showed that magnetic resonance spectroscopy (1H-MRS) optimized for succinate detection (SUCCES) could detect succinate in vivo in both allografted mouse models and PPGL patients. The objective of this study was to prospectively assess the diagnostic performances of 1H-MRS SUCCES sequence for the identification of SDH deficiency in PPGL patients. METHODS: Forty-nine patients presenting with 50 PPGLs were prospectively enrolled in our referral center for 1H-MRS SUCCES. Two observers blinded to the clinical characteristics and genetic status analyzed the presence of a succinate peak and confronted the results to a composite gold standard combining PPGL genetic testing and/or in vitro protein analyses in the tumor. RESULTS: A succinate peak was observed in 20 tumors, all of which had proven SDH deficiency using the gold standard (17 patients with germline SDHx mutations, 2 with a somatic SDHD mutation, and 1 with negative SDHB IHC and SDH loss of function). A false negative result was observed in 3 tumors. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 1H-MRS SUCCES were respectively 87%, 100%, 100%, 90%, and 94%. CONCLUSIONS: Detection of succinate using 1H-MRS is a highly specific and sensitive hallmark of SDH-deficiency in PPGLs.

18F-fluorocholine PET/CT in MEN1 Patients with Primary Hyperparathyroidism.

BACKGROUND: Primary hyperparathyroidism (HPT1) is the most frequent endocrinopathy in multiple endocrine neoplasia type 1 (MEN1). Its surgical management is challenging. We aimed to describe and compare the imaging findings of parathyroid ultrasound (US), sestaMIBI scintigraphy (sestaMIBI), and 18F-fluorocholine (FCH) PET/CT in a series of MEN1 patients with HPT1. METHODS: Retrospective analysis of a cohort of MEN1 patients with HPT1 assessed by parathyroid US, sestaMIBI scintigraphy and SPECT/CT, and FCH-PET/CT for potential surgery between 2015 and 2019. RESULTS: Twenty-two patients with a confirmed diagnosis of MEN1 who presented with HPT1 and were assessed by the 3 imaging modalities were included. After imaging workups, 11 patients were operated on for the first time, 4 underwent a redo surgery, and 7 did not undergo an operation. The overall patient-based positivity rate of imaging was 91% (20 of 22) for parathyroid US and 96% (21 of 22) for both sestaMIBI and FCH-PET/CT. The 3 imaging modalities demonstrated negative findings in 1/22 patient who did not undergo surgery. Overall, 3 pathologic glands were not detected by any imaging technique. SestaMIBI and FCH-PET/CT both resulted in the same 3 false-positive results in ectopic areas with a significant uptake on two thymic carcinoid tumors and one inflammatory lymph node. FCH-PET/CT provided more surgically relevant data than sestaMIBI in 4/11 patients with initial surgery and in 1/4 patient who underwent redo surgery. CONCLUSIONS: Compared to sestaMIBI scintigraphy, FCH-PET/CT provides additional information regarding the number of pathologic parathyroid glands and their localization in MEN1 patients with HPT1.

Intraadrenal corticotropin in bilateral macronodular adrenal hyperplasia.

BACKGROUND: Bilateral macronodular adrenal hyperplasia is a rare cause of primary adrenal Cushing's syndrome. In this form of hyperplasia, hypersecretion of cortisol suppresses the release of corticotropin by pituitary corticotrophs, which results in low plasma corticotropin levels. Thus, the disease has been termed corticotropin-independent macronodular adrenal hyperplasia. We examined the abnormal production of corticotropin in these hyperplastic adrenal glands. METHODS: We obtained specimens of hyperplastic macronodular adrenal tissue from 30 patients with primary adrenal disease. The corticotropin precursor proopiomelanocortin and corticotropin expression were assessed by means of a polymerase-chain-reaction assay and immunohistochemical analysis. The production of corticotropin and cortisol was assessed in 11 specimens with the use of incubated explants and cell cultures coupled with hormone assays. Corticotropin levels were measured in adrenal and peripheral venous blood samples from 2 patients. RESULTS: The expression of proopiomelanocortin messenger RNA (mRNA) was detected in all samples of hyperplastic adrenal tissue. Corticotropin was detected in steroidogenic cells arranged in clusters that were disseminated throughout the adrenal specimens. Adrenal corticotropin levels were higher in adrenal venous blood samples than in peripheral venous samples, a finding that was consistent with local production of the peptide within the hyperplastic adrenals. The release of adrenal corticotropin was stimulated by ligands of aberrant membrane receptors but not by corticotropin-releasing hormone or dexamethasone. A semiquantitative score for corticotropin immunostaining in the samples correlated with basal plasma cortisol levels. Corticotropin-receptor antagonists significantly inhibited in vitro cortisol secretion. CONCLUSIONS: Cortisol secretion by the adrenals in patients with macronodular hyperplasia and Cushing's syndrome appears to be regulated by corticotropin, which is produced by a subpopulation of steroidogenic cells in the hyperplastic adrenals. Thus, the hypercortisolism associated with bilateral macronodular adrenal hyperplasia appears to be corticotropin-dependent. (Funded by the Agence Nationale de la Recherche and others.).

ARMC5 mutations in macronodular adrenal hyperplasia with Cushing's syndrome.

BACKGROUND: Corticotropin-independent macronodular adrenal hyperplasia may be an incidental finding or it may be identified during evaluation for Cushing's syndrome. Reports of familial cases and the involvement of both adrenal glands suggest a genetic origin of this condition. METHODS: We genotyped blood and tumor DNA obtained from 33 patients with corticotropin-independent macronodular adrenal hyperplasia (12 men and 21 women who were 30 to 73 years of age), using single-nucleotide polymorphism arrays, microsatellite markers, and whole-genome and Sanger sequencing. The effects of armadillo repeat containing 5 (ARMC5) inactivation and overexpression were tested in cell-culture models. RESULTS: The most frequent somatic chromosome alteration was loss of heterozygosity at 16p (in 8 of 33 patients for whom data were available [24%]). The most frequent mutation identified by means of whole-genome sequencing was in ARMC5, located at 16p11.2. ARMC5 mutations were detected in tumors obtained from 18 of 33 patients (55%). In all cases, both alleles of ARMC5 carried mutations: one germline and the other somatic. In 4 patients with a germline ARMC5 mutation, different nodules from the affected adrenals harbored different secondary ARMC5 alterations. Transcriptome-based classification of corticotropin-independent macronodular adrenal hyperplasia indicated that ARMC5 mutations influenced gene expression, since all cases with mutations clustered together. ARMC5 inactivation decreased steroidogenesis in vitro, and its overexpression altered cell survival. CONCLUSIONS: Some cases of corticotropin-independent macronodular adrenal hyperplasia appear to be genetic, most often with inactivating mutations of ARMC5, a putative tumor-suppressor gene. Genetic testing for this condition, which often has a long and insidious prediagnostic course, might result in earlier identification and better management. (Funded by Agence Nationale de la Recherche and others.).

Higher risk of death among MEN1 patients with mutations in the JunD interacting domain: a Groupe d'etude des Tumeurs Endocrines (GTE) cohort study.

Multiple endocrine neoplasia syndrome type 1 (MEN1), which is secondary to mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Although genotype-phenotype studies have so far failed to identify any statistical correlations, some families harbor recurrent tumor patterns. The function of MENIN is unclear, but has been described through the discovery of its interacting partners. Mutations in the interacting domains of MENIN functional partners have been shown to directly alter its regulation abilities. We report on a cohort of MEN1 patients from the Groupe d'étude des Tumeurs Endocrines. Patients with a molecular diagnosis and a clinical follow-up, totaling 262 families and 806 patients, were included. Associations between mutation type, location or interacting factors of the MENIN protein and death as well as the occurrence of MEN1-related tumors were tested using a frailty Cox model to adjust for potential heterogeneity across families. Accounting for the heterogeneity across families, the overall risk of death was significantly higher when mutations affected the JunD interacting domain (adjusted HR = 1.88: 95%-CI = 1.15-3.07). Patients had a higher risk of death from cancers of the MEN1 spectrum (HR = 2.34; 95%-CI = 1.23-4.43). This genotype-phenotype correlation study confirmed the lack of direct genotype-phenotype correlations. However, patients with mutations affecting the JunD interacting domain had a higher risk of death secondary to a MEN1 tumor and should thus be considered for surgical indications, genetic counseling and follow-up.

A genome-wide scan identifies mutations in the gene encoding phosphodiesterase 11A4 (PDE11A) in individuals with adrenocortical hyperplasia.

Phosphodiesterases (PDEs) regulate cyclic nucleotide levels. Increased cyclic AMP (cAMP) signaling has been associated with PRKAR1A or GNAS mutations and leads to adrenocortical tumors and Cushing syndrome. We investigated the genetic source of Cushing syndrome in individuals with adrenocortical hyperplasia that was not caused by known defects. We performed genome-wide SNP genotyping, including the adrenocortical tumor DNA. The region with the highest probability to harbor a susceptibility gene by loss of heterozygosity (LOH) and other analyses was 2q31-2q35. We identified mutations disrupting the expression of the PDE11A isoform-4 gene (PDE11A) in three kindreds. Tumor tissues showed 2q31-2q35 LOH, decreased protein expression and high cyclic nucleotide levels and cAMP-responsive element binding protein (CREB) phosphorylation. PDE11A codes for a dual-specificity PDE that is expressed in adrenal cortex and is partially inhibited by tadalafil and other PDE inhibitors; its germline inactivation is associated with adrenocortical hyperplasia, suggesting another means by which dysregulation of cAMP signaling causes endocrine tumors.

Critical role of sorafenib exposure over time for its antitumor activity in thyroid cancer.

Sorafenib, a multi-kinase inhibitor that targets the VEGF, PDGF and BRAF pathways, has demonstrated significant clinical activity in metastatic differentiated thyroid cancer. However, all patients eventually experience disease progression with a median progression-free survival close to 10 months. Since sorafenib exposure is known to decrease over time, we hypothesized that dose adjustments aiming to restore adequate exposure could lead to further clinical activity. We report, as a proof of concept on a patient with radio-iodine resistant metastatic thyroid cancer, who experienced disease progression after an initial response to sorafenib (400 mg twice daily). Whereas the thyroglobulin-progression-free survival at standard doses was 6 months, iterative dose optimization led to a prolonged progression-free survival up to 41 months. Sorafenib doses were increased up to 1600 mg bid, in order to maintain clinical activity, and to restore active plasma concentration, since sorafenib exposure had decreased over the time. Toxicity was mild and manageable for more than 2 years. However, the patient eventually experienced grade 3 proteinuria leading to treatment discontinuation. This observation opens up new horizons for daily management of radioactive iodine-refractory differentiated thyroid cancer patients progressing under standard doses of sorafenib, and stress the need to monitor its plasma concentration.

Carney complex predisposes to breast cancer: prospective study of 50 women.

OBJECTIVE: Carney complex (CNC) is a rare genetic syndrome, mostly due to germline loss-of-function pathogenic variants in PRKAR1A. Carney complex includes pigmented skin lesions, cardiac myxomas, primary pigmented nodular adrenocortical dysplasia, and various breast benign tumors. DESIGN: The present study was designed to describe the characteristics of breast lesions in CNC patients and their association with other manifestations of CNC and PRKAR1A genotype. METHODS: A 3-year follow-up multicenter French prospective study of CNC patients included 50 women who were analyzed for CNC manifestations and particularly breast lesions, with breast imaging, genotyping, and hormonal settings. RESULTS: Among the 38 women with breast imaging, 14 (39%) had breast lesions, half of them bilateral. Ten women (26%) presented with benign lesions and six with breast carcinomas (16%): one had ductal carcinoma in situ at 54, and five had invasive cancer before 50 years old, whom one with contralateral breast cancer during follow-up. The occurrence of breast cancer was more frequent in women with PRKAR1A pathogenic variant odds ratio = 6.34 (1.63-17.91) than in general population of same age. The mean age at breast cancer diagnosis was 44.7 years old: 17 years younger than in the general population. Breast cancer patients had good prognosis factors. All breast carcinomas occurred in individuals with familial CNC and PRKAR1A pathogenic variants. Loss of heterozygosity at the PRKAR1A locus in the 2 invasive breast carcinomas analyzed suggested a driver role of this tumor suppressor gene. CONCLUSIONS: As CNC could predispose to breast carcinoma, an adequate screening strategy and follow-up should be discussed in affected women. CLINICAL TRIAL REGISTRATION: ClinicalTrial.gov NCT00668291.

[Thyroiditis]. / Thyroïdites.

The diagnosis of thyroiditis encompasses a broad spectrum of thyroid disorders. Analysis of signs and symptoms, biochemical changes, neck ultrasound characteristics and radioactive iodine uptake values allows an accurate diagnosis. Recent studies of the whole genome have helped to identify many susceptibility genes for autoimmune thyroiditis. However, none of these genes contribute to a significant increase in risk of developing this thyroiditis. Clinical awareness of the characteristic presentations of exceptional thyroiditis (acute suppurative thyroiditis, Riedel's thyroiditis) is an important issue. Selenium administration seems to be beneficial for reducing the incidence of thyroiditis. Finally, certain drug-induced thyroiditis remains a therapeutic challenge for the physician.