Significant differences between patients with and without PPGL. c Symptom score: one point for each sign: BMI < 25 kg/m 2 , heart rate !85 beats/min, pallor, sweating, palpitations, tremor and nausea; a negative point for obesity.

Background Malignant pheochromocytoma and paraganglioma (MPP) are characterized by prognostic heterogeneity. Our objective was to look for prognostic parameters of overall survival in MPP patients. Patients and Methods Retrospective multicentric study of MPP characterized by a neckthoraco-abdomino-pelvic CT or MRI at the time of malignancy diagnosis in European centers between 1998 and 2010. Results We included 169 patients from 18 European centers. Main characteristics of MPP patients were: primary pheochromocytoma in 53% of patients, tumor or hormone-related symptoms in 57% or 58% of cases, positive plasma or urine hormones in 81% of patients, identification of a mutation in SDHB in 42 % of cases. Metastatic sites included the bone (64%), lymph node (40%), lung (29%) and liver (26%); mean time between initial and malignancy diagnosis was 43 months (0-614). Median follow-up was 68 months and median survival 6.7 years. Using univariate analysis, better survival was associated with head and neck paraganglioma, age <40 years, metanephrines <5-fold the upper limits of the normal range and low proliferative index. In multivariate analysis, hypersecretion (Hazard Ratio 3.02[1.65-5.55]; p:0.0004) was identified as independent significant prognostic factors of worst overall survival. Conclusions Our results do not confirm SDHB mutations as a major prognostic parameter in MPP and suggest additional key molecular events involved in MPP tumor progression. Aside from SDHB mutation, the biology of aggressive MPP remains to be understood.

García-Silva et al. show for the first time that extracellular vesicles isolated from the exudative seroma obtained from the lymphatic drainage implanted in melanoma patients after lymphadenectomy can be interrogated for melanoma markers and BRAF mutations. Profiling the BRAFV600E mutation in this biofluid is a novel approach to predict disease relapse.

Approximately 20% of patients diagnosed with a phaeochromocytoma or paraganglioma carry a germline mutation in one of the succinate dehydrogenase (SDHx) genes (SDHA, SDHB, SDHC and SDHD), which encode the four subunits of the SDH enzyme. When a pathogenic SDHx mutation is identified in an affected patient, genetic counselling is proposed for first-degree relatives. Optimal initial evaluation and follow-up of people who are asymptomatic but might carry SDHx mutations have not yet been agreed. Thus, we established an international consensus algorithm of clinical, biochemical and imaging screening at diagnosis and during surveillance for both adults and children. An international panel of 29 experts from 12 countries was assembled, and the Delphi method was used to reach a consensus on 41 statements. This Consensus Statement covers a range of topics, including age of first genetic testing, appropriate biochemical and imaging tests for initial tumour screening and follow-up, screening for rare SDHx-related tumours and management of elderly people who have an SDHx mutation. This Consensus Statement focuses on the management of asymptomatic SDHx mutation carriers and provides clinicians with much-needed guidance. The standardization of practice will enable prospective studies in the near future.

Mutations that drive the stabilization of hypoxia inducible factor 2α (HIF2α) and downstream pseudohypoxic signaling are known to predispose to the development of pheochromocytomas and paragangliomas (PPGLs). However, any role of HIF2α in predisposition to metastatic disease remains unclear. To assess such a role we combined gene-manipulations in pheochromocytoma cell lines with retrospective analyses of patient data and gene expression profiling in tumor specimens. Among 425 patients with PPGLs identified with mutations in tumor-susceptibility genes, those with tumors due to activation of pseudohypoxic pathways had a higher frequency of metastatic disease than those with tumors due to activation of kinase-signaling pathways, even without inclusion of patients with mutations in SDHB (18.6% vs. 4.3% in, p<0.0001). Three out of nine (33%) of patients with gain-of-function mutations in HIF2α had metastatic disease. In cell line studies, elevated expression of HIF2α enhanced cell proliferation and led to increased migration and invasion capacity. Moreover, HIF2α expression in HIF2α-deficient cells resulted in increased cell motility, diffuse cluster formation and emergence of pseudopodia indicating changes in cell adhesion and cytoskeletal remodeling. In a mouse liver metastasis model, HIF2α enhanced the metastatic load. Transcriptomics data revealed alterations in focal adhesion and extracellular matrix-receptor interactions in HIF2α-mutated PPGLs. Our translational findings demonstrate that HIF2α supports pro-metastatic behavior in PPGLs, though other factors remain critical for subsequent transition to metastasis. We identified LAMB1 and COL4A2 as new potential therapeutic targets for HIF2α-driven PPGLs. Identified HIF2α downstream targets might open a new therapeutic window for aggressive HIF2α-expressing tumors.

Pheochromocytomas and paragangliomas (PPGLs) provide some of the clearest genetic evidence for the critical role of metabolism in the tumorigenesis process. Approximately 40% of PPGLs are caused by driver germline mutations in 16 known susceptibility genes, and approximately half of these genes encode members of the tricarboxylic acid (TCA) cycle. Taking as a starting point the involvement of the TCA cycle in PPGL development, we aimed to identify unreported mutations that occurred in genes involved in this key metabolic pathway and that could explain the phenotypes of additional individuals who lack mutations in known susceptibility genes. To accomplish this, we applied a targeted sequencing of 37 TCA-cycle-related genes to DNA from 104 PPGL-affected individuals with no mutations in the major known predisposing genes. We also performed omics-based analyses, TCA-related metabolite determination, and 13 C 5 -glutamate labeling assays. We identified five germline variants affecting DLST in eight unrelated individuals ($7%); all except one were diagnosed with multiple PPGLs. A recurrent variant, c.1121G>A (p.Gly374Glu), found in four of the eight individuals triggered accumulation of 2-hydroxyglutarate, both in tumors and in a heterologous cell-based assay designed to functionally evaluate DLST variants. p.Gly374Glu-DLST tumors exhibited loss of heterozygosity, and their methylation and expression profiles are similar to those of EPAS1-mutated PPGLs; this similarity suggests a link between DLST disruption and pseudohypoxia. Moreover, we found positive DLST immunostaining exclusively in tumors carrying TCA-cycle or EPAS1 mutations. In summary, this study reveals DLST as a PPGL-susceptibility gene and further strengthens the relevance of the TCA cycle in PPGL development.

Purpose: Paclitaxel, a widely used chemotherapeutic drug, can cause peripheral neuropathies leading to dose reductions and treatment suspensions and decreasing the quality of life of patients. It has been suggested that genetic variants altering paclitaxel pharmacokinetics increase neuropathy risk, but the major causes of interindividual differences in susceptibility to paclitaxel toxicity remain unexplained. We carried out a wholeexome sequencing (WES) study to identify genetic susceptibility variants associated with paclitaxel neuropathy.Experimental Design: Blood samples from 8 patients with severe paclitaxel-induced peripheral neuropathy were selected for WES. An independent cohort of 228 cancer patients with complete paclitaxel neuropathy data was used for variant screening by DHPLC and association analysis. HEK293 cells were used for heterologous expression and characterization of two novel CYP3A4 enzymes.Results: WES revealed 2 patients with rare CYP3A4 variants, a premature stop codon (CYP3A4 Ã 20 allele) and a novel missense variant (CYP3A4 Ã 25, p.P389S) causing reduced enzyme expression. Screening for CYP3A4 variants in the independent cohort revealed three additional CYP3A4 Ã 20 carriers, and two patients with missense variants exhibiting diminished enzyme activity (CYP3A4 Ã 8 and the novel CYP3A4 Ã 27 allele, p.L475V). Relative to CYP3A4 wild-type patients, those carrying CYP3A4 defective variants had more severe neuropathy (2-and 1.3-fold higher risk of neuropathy for loss-of-function and missense variants, respectively, P ¼ 0.045) and higher probability of neuropathy-induced paclitaxel treatment modifications (7-and 3-fold higher risk for loss-of-function and missense variants, respectively, P ¼ 5.9 Â 10 À5 ).Conclusion: This is the first description of a genetic marker associated with paclitaxel treatment modifications caused by neuropathy. CYP3A4 defective variants may provide a basis for paclitaxel treatment individualization.

Context Pheochromocytomas and paragangliomas (PPGLs) are characterized by distinct genotype-phenotype relationships according to studies largely restricted to Caucasian populations. Objective To assess for possible differences in genetic landscapes and genotype-phenotype relationships of PPGLs in Chinese versus European populations. Design Cross-sectional study. Setting Two tertiary-care centers in China and nine in Europe. Participants Patients with pathologically-confirmed diagnosis of PPGL, including 719 from China and 919 Europeans. Main Outcome Measures Next generation sequencing performed in tumor specimens with mutations confirmed by Sanger sequencing and tested in peripheral blood if available. Frequencies of mutations were examined according to tumor location and catecholamine biochemical phenotypes. Results Among all patients, higher frequencies of HRAS, FGFR1 and EPAS1 mutations were observed in Chinese than Europeans, whereas the reverse was observed for NF1, VHL, RET and SDHx. Among patients with apparently sporadic PPGLs, the most frequently mutated genes in Chinese were HRAS (16.5[13.6-19.3]% vs 9.8[7.6-12.1]%) and FGFR1 (9.8[7.6-12.1]% vs 2.2[1.1-3.3]%), whereas among Europeans the most frequently mutated genes were NF1 (15.9[13.2-18.6]% vs 6.6[4.7-8.5]%) and SDHx (10.7[8.4-13.0]% vs 4.2[2.6-5.7]%). Among Europeans, almost all paragangliomas lacked appreciable production of epinephrine and identified gene mutations were largely restricted to those leading to stabilization of hypoxia inducible factors. In contrast, among Chinese there was a larger proportion of epinephrine-producing paragangliomas, mostly due to HRAS and FGFR1 mutations. Conclusions This study establishes Sino-European differences in the genetic landscape and presentation of PPGLs, including ethnic differences in genotype-phenotype relationships indicating a paradigm shift in our understanding of the biology of these tumors.