Outcomes of adrenal-sparing surgery or total adrenalectomy in phaeochromocytoma associated with multiple endocrine neoplasia type 2: an international retrospective population-based study.

BACKGROUND: The prevention of medullary thyroid cancer in patients with multiple endocrine neoplasia type 2 syndrome has demonstrated the ability of molecular diagnosis and prophylactic surgery to improve patient outcomes. However, the other major neoplasia associated with multiple endocrine neoplasia type 2, phaeochromocytoma, is not as well characterised in terms of occurrence and treatment outcomes. In this study, we aimed to systematically characterise the outcomes of management of phaeochromocytoma associated with multiple endocrine neoplasia type 2. METHODS: This multinational observational retrospective population-based study compiled data on patients with multiple endocrine neoplasia type 2 from 30 academic medical centres across Europe, the Americas, and Asia. Patients were included if they were carriers of germline pathogenic mutations of the RET gene, or were first-degree relatives with histologically proven medullary thyroid cancer and phaeochromocytoma. We gathered clinical information about patients'RET genotype, type of treatment for phaeochromocytoma (ie, unilateral or bilateral operations as adrenalectomy or adrenal-sparing surgery, and as open or endoscopic operations), and postoperative outcomes (adrenal function, malignancy, and death). The type of surgery was decided by each investigator and the timing of surgery was patient driven. The primary aim of our analysis was to compare disease-free survival after either adrenal-sparing surgery or adrenalectomy. FINDINGS: 1210 patients with multiple endocrine neoplasia type 2 were included in our database, 563 of whom had phaeochromocytoma. Treatment was adrenalectomy in 438 (79%) of 552 operated patients, and adrenal-sparing surgery in 114 (21%). Phaeochromocytoma recurrence occurred in four (3%) of 153 of the operated glands after adrenal-sparing surgery after 6-13 years, compared with 11 (2%) of 717 glands operated by adrenalectomy (p=0.57). Postoperative adrenal insufficiency or steroid dependency developed in 292 (86%) of 339 patients with bilateral phaeochromocytoma who underwent surgery. However, 47 (57%) of 82 patients with bilateral phaeochromocytoma who underwent adrenal-sparing surgery did not become steroid dependent. INTERPRETATION: The treatment of multiple endocrine neoplasia type 2-related phaeochromocytoma continues to rely on adrenalectomies with their associated Addisonian-like complications and consequent lifelong dependency on steroids. Adrenal-sparing surgery, a highly successful treatment option in experienced centres, should be the surgical approach of choice to reduce these complications.

Overexpression of the insulin-like growth factor 1 receptor (IGF-1R) is associated with malignancy in familial pheochromocytomas and paragangliomas.

CONTEXT: Pheochromocytomas and paragangliomas (pheo/pgl) are neuroendocrine tumours derived from chromaffin cells. Although mostly benign, up to 26% of pheo/pgl will undergo malignant transformation. Reliable histological signs to differentiate benign pheo/pgl from malignant tumours are currently lacking. Increased IGF-1R expression has been shown during progression to metastatic phenotypes of several types of cancer. OBJECTIVE: To analyse the distribution and expression of the IGF-1R in pheo/pgl of different genetic origin and degree of malignancy. MEASUREMENTS: We studied the expression of the IGF-1R protein by immunohistochemistry, in 40 primary tumours from patients with pheo/pgl from different genetic aetiology (11 of 29 metastatic/nonmetastatic diseases). RESULTS: We found a strong association between increased expression of IGF-1R and malignant behaviour regardless of the age at diagnosis and the genetic aetiology. IGF-1R labelling was mostly weak in primary tumours from patients with nonmetastatic pheo/pgl. Conversely, intense IGF-1R labelling was predominant in cases of pheo/pgl with confirmed metastatic disease. The risk of metastases was 11·7 times higher if tumour IGF-1R labelling was intense independently of age at diagnosis. The probability of remaining free of metastases was higher in patients with pheo/pgl scored weak for IGF-1R at 60 months and more than twofold higher at 120 months of follow-up than in patients with intense IGF-1R labelling in their primary tumours. CONCLUSIONS: Our results strongly suggest that IGF-1R is associated with malignancy in familial pheo/pgl and that IGF-1R expression in the primary tumour might be a useful tool to detect those patients harbouring pheo/pgl who have an increased risk of metastasis.

VHL-P138R and VHL-L163R Novel Variants: Mechanisms of VHL Pathogenicity Involving HIF-Dependent and HIF-Independent Actions.

The von Hippel-Lindau (VHL) disease is an autosomal dominant cancer syndrome caused by mutations in the VHL tumor suppressor gene. VHL protein (pVHL) forms a complex (VBC) with Elongins B-C, Cullin2, and Rbx1. Although other functions have been discovered, the most described function of pVHL is to recognize and target hypoxia-inducible factor (HIF) for degradation. This work comprises the functional characterization of two novel variants of the VHL gene (P138R and L163R) that have been described in our center in patients with VHL disease by in vitro, in vivo, and in silico approaches. In vitro, we found that these variants have a significantly shorter half-life compared to wild-type VHL but still form a functional VBC complex. Altered fibronectin deposition was evidenced for both variants using immunofluorescence. In vivo studies revealed that both variants failed to suppress tumor growth. By means of molecular dynamics simulations, we inspected in silico the nature of the changes introduced by each variant in the VBC complex. We have demonstrated the pathogenicity of P138R and L163R novel variants, involving HIF-dependent and HIF-independent mechanisms. These results provide the basis for future studies regarding the impact of structural alterations on posttranslational modifications that drive pVHL's fate and functions.

Risk profiles and penetrance estimations in multiple endocrine neoplasia type 2A caused by germline RET mutations located in exon 10.

Multiple endocrine neoplasia type 2 is characterized by germline mutations in RET. For exon 10, comprehensive molecular and corresponding phenotypic data are scarce. The International RET Exon 10 Consortium, comprising 27 centers from 15 countries, analyzed patients with RET exon 10 mutations for clinical-risk profiles. Presentation, age-dependent penetrance, and stage at presentation of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism were studied. A total of 340 subjects from 103 families, age 4-86, were registered. There were 21 distinct single nucleotide germline mutations located in codons 609 (45 subjects), 611 (50), 618 (94), and 620 (151). MTC was present in 263 registrants, pheochromocytoma in 54, and hyperparathyroidism in 8 subjects. Of the patients with MTC, 53% were detected when asymptomatic, and among those with pheochromocytoma, 54%. Penetrance for MTC was 4% by age 10, 25% by 25, and 80% by 50. Codon-associated penetrance by age 50 ranged from 60% (codon 611) to 86% (620). More advanced stage and increasing risk of metastases correlated with mutation in codon position (609→620) near the juxtamembrane domain. Our data provide rigorous bases for timing of premorbid diagnosis and personalized treatment/prophylactic procedure decisions depending on specific RET exon 10 codons affected.

Genotype-Phenotype Features of Germline Variants of the TMEM127 Pheochromocytoma Susceptibility Gene: A 10-Year Update.

PURPOSE: This work aimed to evaluate genotype-phenotype associations in individuals carrying germline variants of transmembrane protein 127 gene (TMEM127), a poorly known gene that confers susceptibility to pheochromocytoma (PHEO) and paraganglioma (PGL). DESIGN: Data were collected from a registry of probands with TMEM127 variants, published reports, and public databases. MAIN OUTCOME ANALYSIS: Clinical, genetic, and functional associations were determined. RESULTS: The cohort comprised 110 index patients (111 variants) with a mean age of 45 years (range, 21-84 years). Females were predominant (76 vs 34, P < .001). Most patients had PHEO (n = 94; 85.5%), although PGL (n = 10; 9%) and renal cell carcinoma (RCC, n = 6; 5.4%) were also detected, either alone or in combination with PHEO. One-third of the cases had multiple tumors, and known family history was reported in 15.4%. Metastatic PHEO/PGL was rare (2.8%). Epinephrine alone, or combined with norepinephrine, accounted for 82% of the catecholamine profiles of PHEO/PGLs. Most variants (n = 63) occurred only once and 13 were recurrent (2-12 times). Although nontruncating variants were less frequent than truncating changes overall, they were predominant in non-PHEO clinical presentations (36% PHEO-only vs 69% other, P < .001) and clustered disproportionately within transmembrane regions (P < .01), underscoring the relevance of these domains for TMEM127 function. Integration of clinical and previous experimental data supported classification of variants into 4 groups based on mutation type, localization, and predicted disruption. CONCLUSIONS: Patients with TMEM127 variants often resemble sporadic nonmetastatic PHEOs. PGL and RCC may also co-occur, although their causal link requires further evaluation. We propose a new classification to predict variant pathogenicity and assist with carrier surveillance.

Spectrum and prevalence of FP/TMEM127 gene mutations in pheochromocytomas and paragangliomas.

CONTEXT: Pheochromocytomas and paragangliomas are genetically heterogeneous neural crest-derived neoplasms. We recently identified germline mutations of the novel transmembrane-encoding gene FP/TMEM127 in familial and sporadic pheochromocytomas consistent with a tumor suppressor effect. OBJECTIVES: To examine the prevalence and spectrum of FP/TMEM127 mutations in pheochromocytomas and paragangliomas and to test the effect of mutations in vitro. DESIGN, SETTING, AND PARTICIPANTS: We sequenced the FP/TMEM127 gene in 990 individuals with pheochromocytomas and/or paragangliomas, including 898 previously unreported cases without mutations in other susceptibility genes from 8 independent worldwide referral centers between January 2009 and June 2010. A multiplex polymerase chain reaction-based method was developed to screen for large gene deletions in 545 of these samples. Confocal microscopy of 5 transfected mutant proteins was used to determine their subcellular localization. MAIN OUTCOME MEASURES: The frequency and type of FP/TMEM127 mutation or deletion was assessed and correlated with clinical variables; the subcellular localization of 5 overexpressed mutants was compared with wild-type FP/TMEM127 protein. RESULTS: We identified 19 potentially pathogenic FP/TMEM127 germline mutations in 20 independent families, but no large deletions were detected. All mutation carriers had adrenal tumors, including 7 bilateral (P = 2.7 × 10(-4)) and/or with familial disease (5 of 20 samples; P = .005). The median age at disease onset in the FP/TMEM127 mutation group was similar to that of patients without a mutation (41.5 vs 45 years, respectively; P = .54). The most common presentation was that of a single benign adrenal tumor in patients older than 40 years. Malignancy was seen in 1 mutation carrier (5%). Expression of 5 novel FP/TMEM127 mutations in cell lines revealed diffuse localization of the mutant proteins in contrast with the discrete multiorganelle distribution of wild-type TMEM127. CONCLUSIONS: Germline mutations of FP/TMEM127 were associated with pheochromocytoma but not paraganglioma and occurred in an age group frequently excluded from genetic screening algorithms. Disease-associated mutations disrupt intracellular distribution of the FP/TMEM127 protein.

Cytochrome 450 metabolites of arachidonic acid (20-HETE, 11,12-EET and 14,15-EET) promote pheochromocytoma cell growth and tumor associated angiogenesis.

The importance of cytochrome P450 (CYP)-derived arachidonic acid (AA) metabolites, 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs) as tumor growth promotors has already been described in several cancer types. The aim of this study was to evaluate the role of these compounds in the biology of pheochromocytoma/paraganglioma. These tumors originate from chromaffin cells derived from adrenal medulla (pheochromocytomas) or extra-adrenal autonomic paraganglia (paragangliomas), and they represent the most common hereditary endocrine neoplasia. According to mutations in the driver genes, these tumors are divided in two clusters: pseudo-hypoxic and kinase-signaling EETs, but not 20-HETE, exhibited a potent ability to sustain growth in a murine pheochromocytoma cell line (MPC) in vitro, EETs promoted an increase in cell proliferation and a decrease in cell apoptosis. In a mouse model of pheochromocytoma, the inhibition of CYP-mediated AA metabolism using 1-aminobenzotriazol resulted in slower tumor growth, a decreased vascularization, and a lower final volume. Also, the expression of AA-metabolizing CYP monooxygenases was detected in tumor samples from human origin, being their apparent abundance and the production of both metabolites higher in tumors from the kinase-signaling cluster. This is the first evidence of the importance of CYP- derived AA metabolites in the biology and development of pheochromocytoma/paraganglioma tumors.

Age-related neoplastic risk profiles and penetrance estimations in multiple endocrine neoplasia type 2A caused by germ line RET Cys634Trp (TGC>TGG) mutation.

RET testing in multiple endocrine neoplasia type 2 for molecular diagnosis is the paradigm for the practice of clinical cancer genetics. However, precise data for distinct mutation-based risk profiles are not available. Here, we survey the clinical profile for one specific genotype as a model, TGC to TGG in codon 634 (C634W). By international efforts, we ascertained all available carriers of the RET C634W mutation. Age at diagnosis, penetrance, and clinical complications were analyzed for medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism (HPT), as well as overall survival. Our series comprises 92 carriers from 20 unrelated families worldwide. Sixty-eight subjects had MTC diagnosed at age 3-72 years (mean 29). Lymph node metastases were observed in 16 subjects aged 20-72 and distant metastases in 4 subjects aged 28-69. Forty-one subjects had pheochromocytoma detected at age 18-67 (mean 36). Amongst the 28 subjects with MTC and pheochromocytoma, six developed pheochromocytoma before MTC. Six subjects had HPT diagnosed at age 26-52 (mean 39). Eighteen subjects died; of the 16 with known causes of death, 8 died of pheochromocytoma and 4 of MTC. Penetrance for MTC is 52% by age 30 and 83% by age 50, for pheochromocytoma penetrance is 20% by age 30 and 67% by age 50, and for HPT penetrance is 3% by age 30 and 21% by age 50. These data provide, for the first time, RET C634W-specific neoplastic risk and age-related penetrance profiles. The data may facilitate risk assessment and genetic counseling.

Possible autocrine enkephalin regulation of catecholamine release in human pheochromocytoma cells.

AIMS: Pheochromocytomas are catecholamine-secreting tumors that also synthesize and secrete several neuropeptides, including opioids. A negative regulation of catecholamine secretion by opioids has been postulated in chromaffin cells. However, results obtained so far are contradictory when referred to human pheochromocytomas. The aim of this study was to define the role of locally produced enkephalins on catecholamine release in human pheochromocytoma cells. MAIN METHODS: Cells obtained from eleven human pheochromocytomas of different genetic origins were cultured for 5 days. Cultures were maintained under basal condition or under enkephalin, dexamethasone and naloxone alone or in combination with enkephalin or dexamethasone-stimulated conditions. Catecholamine and enkephalin levels in the culture medium were measured by HPLC-ED and RIA respectively. KEY FINDINGS: Enkephalin induced a decrease in norepinephrine levels in all tumor cultures. Dexamethasone treatment, which increased enkephalin levels, also decreased catecholamine levels. On the other hand, the addition of naloxone to the cultures reverted to normal the inhibitory action exerted by enkephalin and dexamethasone treatments. SIGNIFICANCE: These results suggest the existence of an autocrine negative regulatory loop exerted by enkephalin on norepinephrine release in human pheochromocytoma cells.

Plasma melatonin pattern in chronic and episodic headaches: evaluation during sleep and waking.

To look for a relationship between pineal function in chronic migraine (CM), cluster headache (CH) (during active and remission periods), chronic tension-type headache (CTTH) patients and controls during NREM sleep, REM sleep and waking, we performed serial sampling of plasma melatonin in the different sleep stages during the first half of the night, in order to avoid chronobiological interferences. Plasma melatonin levels did not show a normal curve either in the CTTH or in the CM patients and no significant differences between these groups were found in any of the sleep stages studied. Plasma melatonin values of CH patients during the cluster period showed an abnormal pattern. The curve showed a pathological lack of peaks during the active period, melatonin levels remaining within normal daytime range throughout the study. A trend to normalization of the curve during the remission period was observed. On the basis of these different melatonin secretion patterns, it might be hypothesized that the involvement of the hypothalamus in chronic-type headaches differs from that displayed in episodic forms.

Germline NF1 mutational spectra and loss-of-heterozygosity analyses in patients with pheochromocytoma and neurofibromatosis type 1.

BACKGROUND: Neurofibromatosis type 1 (NF1) is a pheochromocytoma-associated syndrome. Because of the low prevalence of pheochromocytoma in NF1, we ascertained subjects by pheochromocytoma that also had NF1 in the hope of describing the germline NF1 mutational spectra of NF1-related pheochromocytoma. MATERIALS AND METHODS: An international registry for NF1-pheochromocytomas was established. Mutation scanning was performed using denaturing HPLC for intragenic variation and quantitative PCR for large deletions. Loss-of-heterozygosity analysis using markers in and around NF1 was performed. RESULTS: There were 37 eligible subjects (ages 14-70 yr). Of 21 patients with corresponding tumor available, 67% showed somatic loss of the nonmutated allele at the NF1 locus vs. 0 of 12 sporadic tumors (P = 0.0002). Overall, 86% of the 37 patients had exonic or splice site mutations, 14% large deletions or duplications; 79% of the mutations are novel. The cysteine-serine rich domain (CSR) was affected in 35% but the RAS GTPase activating protein domain (RGD) in only 13%. There did not appear to be an association between any clinical features, particularly pheochromocytoma presentation and severity, and NF1 mutation genotype. CONCLUSIONS: The germline NF1 mutational spectra comprise intragenic mutations and deletions in individuals with pheochromocytoma and NF1. NF1 mutations tended to cluster in the CSR over the RAS-GAP domain, suggesting that CSR plays a more prominent role in individuals with NF1-pheochromocytoma than in NF1 individuals without this tumor. Loss-of-heterozygosity of NF1 markers in NF1-related pheochromocytoma was significantly more frequent than in sporadic pheochromocytoma, providing further molecular evidence that pheochromocytoma is a true component of NF1.

Acceleration of luteinizing hormone pulse frequency in adolescent girls with a history of central precocious puberty with versus without hyperandrogenism.

UNLABELLED: Some adolescents with a history of idiopathic central precocious puberty (ICPP) develop hyperandrogenism. HYPOTHESIS: Luteinizing hormone (LH) hypersecretion could be a common mechanism underlying ICPP and polycystic ovary syndrome. AIM: To explore the GnRH-LH axis in those patients. DESIGN: To compare overnight LH secretion in 7 healthy adolescents (CG) with that in patients with prior ICPP [5 with (CPPA) and 7 without (CPPB) hyperandrogenism]. To analyze daytime LH secretion in those patients. METHODS: LH secretion was quantified by immunofluorometry and deconvolution analysis. RESULTS: Nighttime mean LH (international units/liter) was higher in CPPA (6.9 +/- 1.5) than in CPPB (3.2 +/- 0.4, p < 0.05) and CG (2.9 +/- 0.4, p < 0.01). Deconvolution analysis revealed a greater nighttime LH frequency (pulses/hour) both in CPPA (0.91 +/- 0.06, p < 0.01) and CPPB (0.74 +/- 0.02, p < 0.05) than in CG (0.45 +/- 0.07). CPPA patients maintained a higher frequency than CPPB. Pulsatile LH production was greater in CPPA than in CG (50 +/- 12 vs. 18 +/- 3 IU/l/day, p < 0.01). Daytime mass of LH released per burst and pulsatile production rate were significantly greater in CPPA than in CPPB patients. CONCLUSIONS: Hyperandrogenic adolescents with prior ICPP show increased pulsatile LH secretion. Augmentation of LH pulsatility may predispose to or cause hyperandrogenism in some adolescents with a history of precocious puberty.

Characteristics of pheochromocytoma in a 4- to 20-year-old population.

Hypertension in children and adolescents has become a major health problem recently recognized, and in a significant number of patients it is due to an endocrine tumor. The aim of this study was to establish the characteristics of pheochromocytoma in a population of 58 patients between 4 and 20 years of age studied at our Center. They represented a 23% of the total population of 255 pheochromocytoma patients studied. In the younger group (under 20 years of age), there was a marked predominance of severe sustained hypertension (93%), only 7% presented paroxysmal hypertension and none of them was normotensive. The youngsters studied showed a higher incidence of bilateral adrenal pheochromocytoma (34%) and extra-adrenal pheochromocytoma (22%). Malignancy was found in 12% of these patients. In addition, the incidence of familial pheochromocytoma was elevated in these patients (39%). Surprisingly, in contrast with the adult population where the most frequent familial pheochromocytomas were multiple endocrine neoplasia (MEN) type 2A (15%), the younger population showed a higher predominance of von Hippel-Lindau (VHL) (28%) and lower incidence of MEN 2A, MEN 2B, neurofibromatosis (NF), and succinate dehydrogenase subunit B (SDHB). In the VHL group, only two patients belonging to one family, showed the R167W mutation, while the others showed novel mutations in conserved amino acids. It may be speculated that the high incidence of VHL in youngsters may account for the biochemical and clinical features they usually present.

VHL Germline Mutations in Argentinian Patients with Clinical Diagnoses or Single Typical Manifestations of Type 1 von Hippel-Lindau Disease.

AIMS: von Hippel-Lindau (VHL) disease is caused by mutations in the VHL tumor suppressor gene. As tumors that develop in the context of VHL also occur in a sporadic context, the frequency of this syndrome may be underestimated. Our aim was to identify VHL gene mutations in Argentinian patients who fulfilled the clinical criteria for type 1 VHL disease and in patients with VHL-associated manifestations that did not meet these criteria. METHODS: We performed a retrospective cohort study, including patients who met current diagnostic criteria for type 1 VHL (Group 1, n = 19) and patients with VHL-associated manifestations that did not meet these criteria (Group 2, n = 21). Genomic DNA was extracted from peripheral blood leukocytes. Mutation analysis involved DNA sequencing, while large deletions were determined by universal primer quantitative fluorescent multiplex polymerase chain reaction (UPQFM-PCR) and multiplex ligation-dependent probe amplification (MLPA) analysis. RESULTS: VHL mutations were detected in 16/19 (84.2%) patients in Group 1 and included: gross deletions (4/16); nonsense mutations (6/16); frameshift mutations (4/16); missense mutations (1/16); and splicing mutations (1/16). Three of these mutations were novel. No alterations were found in 3 of 19 VHL patients. In Group 2, one nonsense VHL mutation was detected in a young patient with a solitary central nervous system hemangioblastoma without familial history. A study of 30 first-degree relatives revealed four carriers with VHL mutations. CONCLUSIONS: We found three novel mutations in the VHL gene in our population. Our results emphasize the importance of a complete genetic study of VHL to confirm type 1 VHL disease, not only in patients with clinical diagnostic criteria but also in those presenting a single typical manifestation.

Recurrent Mutations of Chromatin-Remodeling Genes and Kinase Receptors in Pheochromocytomas and Paragangliomas.

PURPOSE: Pheochromocytomas and paragangliomas (PPGL) are genetically heterogeneous tumors of neural crest origin, but the molecular basis of most PPGLs is unknown. EXPERIMENTAL DESIGN: We performed exome or transcriptome sequencing of 43 samples from 41 patients. A validation set of 136 PPGLs was used for amplicon-specific resequencing. In addition, a subset of these tumors was subjected to microarray-based transcription, protein expression, and histone methylation analysis by Western blotting or immunohistochemistry. In vitro analysis of mutants was performed in cell lines. RESULTS: We detected mutations in chromatin-remodeling genes, including histone-methyltransferases, histone-demethylases, and histones in 11 samples from 8 patients (20%). In particular, we characterized a new cancer syndrome involving PPGLs and giant cell tumors of bone (GCT) caused by a postzygotic G34W mutation of the histone 3.3 gene, H3F3A Furthermore, mutations in kinase genes were detected in samples from 15 patients (37%). Among those, a novel germline kinase domain mutation of MERTK detected in a patient with PPGL and medullary thyroid carcinoma was found to activate signaling downstream of this receptor. Recurrent germline and somatic mutations were also detected in MET, including a familial case and sporadic PPGLs. Importantly, in each of these three genes, mutations were also detected in the validation group. In addition, a somatic oncogenic hotspot FGFR1 mutation was found in a sporadic tumor. CONCLUSIONS: This study implicates chromatin-remodeling and kinase variants as frequent genetic events in PPGLs, many of which have no other known germline driver mutation. MERTK, MET, and H3F3A emerge as novel PPGL susceptibility genes. Clin Cancer Res; 22(9); 2301-10. ©2015 AACR.

Characterization of endolymphatic sac tumors and von Hippel-Lindau disease in the International Endolymphatic Sac Tumor Registry.

BACKGROUND: Endolymphatic sac tumors (ELSTs) are, with a prevalence of up to 16%, a component of von Hippel-Lindau (VHL) disease. Data from international registries regarding heritable fraction and characteristics, germline VHL mutation frequency, and prevalence are lacking. METHODS: Systematic registration of ELSTs from international centers of otorhinolaryngology and from multidisciplinary VHL centers' registries was performed. Molecular genetic analyses of the VHL gene were offered to all patients. RESULTS: Our population-based registry comprised 93 patients with ELST and 1789 patients with VHL. The prevalence of VHL germline mutations in apparently sporadic ELSTs was 39%. The prevalence of ELSTs in patients with VHL was 3.6%. ELST was the initial manifestation in 32% of patients with VHL-ELST. CONCLUSION: Prevalence of ELST in VHL disease is much lower compared to the literature. VHL-associated ELSTs can be the first presentation of the syndrome and mimic sporadic tumors, thus emphasizing the need of molecular testing in all presentations of ELST. © 2015 Wiley Periodicals, Inc. Head Neck 38: 673-679, 2016.

Amplified and orderly growth hormone secretion characterizes lean adolescents with polycystic ovary syndrome.

OBJECTIVE: The present study evaluated the hypothesis that pulsatile GH secretion is altered in adolescents with polycystic ovary syndrome (PCOS). DESIGN AND PATIENTS: Thirteen adolescent girls with PCOS (ages 13-19 years) and ten eumenorrheic controls (ages 14-19 years) matched for a range of body mass index (BMI) values underwent blood sampling every 20 min for 12 h overnight. METHODS: Serum concentrations of GH and LH were measured by specific immunofluorometric assays (IFMA). Pulsatile secretion was quantitated by deconvolution analysis and pattern orderliness by the approximate entropy (ApEn) statistic. Fasting serum androstenedione, testosterone, 17-hydroxyprogesterone, estrone, estradiol, insulin and IGF-I concentrations were measured by RIA, GH-binding protein (GHBP) by IFMA and IGF-binding protein (IGFBP)-1 and IGFBP-3 by IRMA. RESULTS: Twelve-hour mean and integrated GH concentrations, the mass of GH secreted per burst, and the GH pulse frequency were not distinguishable in patients with PCOS and controls as a whole. Subanalysis of non-obese (BMI<25 kg/m(2)) PCOS and healthy volunteers disclosed elevated 12-h GH production rates (P=0.03) and integrated serum GH concentrations (P=0.04) in (lean) patients with PCOS. ApEn analysis of the orderliness of GH release showed remarkably more regular GH secretion patterns (lower ApEn of GH release) in girls with PCOS compared with controls (P=0.02). Serum GHBP, IGF-I and IGFBP-3 concentrations were similar in both groups, whether lean or obese. However, IGFBP-1 levels were lower in the combined group of PCOS subjects compared with BMI-matched controls (P<0.05). In volunteers with PCOS, mean (12-h) serum GH concentrations correlated positively with mean serum LH levels (P=0.006). Based on deconvolution analysis, the 12-h production rate and the mass of GH secreted per burst also correlated strongly with the cognate LH measure (both predicted) (P=0.004) in PCOS. Androstenedione levels were also related to the 12-h GH secretion rate (P=0.02). CONCLUSIONS: This study shows that non-obese adolescents with PCOS secrete GH at a higher rate and with more orderly patterns, resembling a male profile. Determining whether this pattern reflects an intrinsic hypothalamic abnormality or is secondary to androgen excess in PCOS will require further studies.

Familial isolated pheochromocytoma presenting a new mutation in the von Hippel-Lindau gene.

We report a novel germ-line point mutation in the von Hippel-Lindau (vhl) gene in a family with childhood occurrence of isolated pheochromocytoma. Two members of this family (the father and his son) were affected. The son had bilateral adrenal pheochromocytoma and the father had one adrenal and one extra-adrenal localization. Both patients presented cardiac arrest while exposed to surgical stress and severe hypoglycemia was registered in the son. The outcome was uneventful. A DNA sequence analysis of vhl tumor suppressor gene revealed the L163R mutation. This new mutation may be specifically associated with the von Hippel-Lindau type 2C disease phenotype. Whether this mutation is linked to the metabolic alterations developed by these patients remains to be determined.

Normal sympathetic nervous system response in reflex sympathetic dystrophy.

We evaluated sympathetic nervous system activity by sympathetic skin response (SSR) recording and we further investigated sympathetic and opioid outflow indirectly in patients with features of reflex sympathetic dystrophy by measuring concentrations of plasma catecholamines (CAs) and their metabolites and plasma metenkephalin (ME), before and after corticoid treatment. Six patients were studied. Basal SSR latencies, morphologies and amplitudes were normal in five patients. In one woman, latency and amplitude were also normal but the morphology was disturbed. Basal plasma ME, CA and metabolite levels were similar in the affected and non-affected limbs and a significant increase in plasma ME concentrations was observed in both affected and non-affected limbs after two weeks of steroid treatment. Altogether these results point to an adaptive supersensitivity rather than a sympathetic hyperactivity in this syndrome; also, they indicate that the therapeutic effect of steroids adds, to their known anti-inflammatory action, a stimulatory action on the endogenous opioid system.

Pheochromocytoma associated with pregnancy: unexpected favourable outcome in patients diagnosed after delivery.

OBJECTIVE: The objective of this study is to present the clinical findings and outcome of a large cohort of pregnant women with pheochromocytoma (PHEO) with the aim to contribute to the better recognition, detection and management of pregnancy-related PHEO in the population of pregnant patients with hypertension. METHODS: This is a longitudinal follow-up of a single cohort of 15 patients aged 19-40 years with PHEO associated with pregnancy. Urinary catecholamines and vanillylmandelic acid (VMA) were analysed. Ret proto-oncogene, SDHB and VHL mutations were determined in germline DNA from seven women using PCR followed by direct sequencing. RESULTS: During pregnancy, all women presented typical features of catecholamines excess. Nevertheless, biochemical diagnosis was performed only in four out of 15 cases during pregnancy and postpartum in the remaining 11. Paroxysmal hypertension was the predominant pattern. Urinary catecholamines and/or VMA were increased in all patients. Tumours were adrenal in 13 patients and extraadrenal in two. Mutations in the Ret proto-oncogene were found in four patients, in the VHL gene in one and in the SDHB gene in one. Antihypertensive treatment resulted in effective control of blood pressure and all women survived. In the group of women diagnosed postpartum, one foetus demised. Newborns from mothers receiving adequate treatment survived. One woman left the hospital after caesarean section but before PHEO surgery became pregnant again and this gestation ended with maternal-foetal dead. CONCLUSION: A high index of suspicion in all pregnant women presenting hypertension mainly paroxystic during any gestational phase and/or a history of familial PHEO are the keys to disclose this important diagnosis.