Summary Background Phaeochromocytomas and paragangliomas are neuro-endocrine tumours that occur sporadically and in several hereditary tumour syndromes, including the phaeochromocytoma–paraganglioma syndrome. This syndrome is caused by germline mutations in succinate dehydrogenase B (SDHB), C (SDHC), or D (SDHD) genes. Clinically, the phaeochromocytoma–paraganglioma syndrome is often unrecognised, although 10–30% of apparently sporadic phaeochromocytomas and paragangliomas harbour germline SDH-gene mutations. Despite these figures, the screening of phaeochromocytomas and paragangliomas for mutations in the SDH genes to detect phaeochromocytoma–paraganglioma syndrome is rarely done because of time and financial constraints. We investigated whether SDHB immunohistochemistry could effectively discriminate between SDH-related and non-SDH-related phaeochromocytomas and paragangliomas in large retrospective and prospective tumour series. Methods Immunohistochemistry for SDHB was done on 220 tumours. Two retrospective series of 175 phaeochromocytomas and paragangliomas with known germline mutation status for phaeochromocytoma-susceptibility or paraganglioma-susceptibility genes were investigated. Additionally, a prospective series of 45 phaeochromocytomas and paragangliomas was investigated for SDHB immunostaining followed by SDHB, SDHC, and SDHD mutation testing. Findings SDHB protein expression was absent in all 102 phaeochromocytomas and paragangliomas with an SDHB, SDHC, or SDHD mutation, but was present in all 65 paraganglionic tumours related to multiple endocrine neoplasia type 2, von Hippel–Lindau disease, and neurofibromatosis type 1. 47 (89%) of the 53 phaeochromocytomas and paragangliomas with no syndromic germline mutation showed SDHB expression. The sensitivity and specificity of the SDHB immunohistochemistry to detect the presence of an SDH mutation in the prospective series were 100% (95% CI 87–100) and 84% (60–97), respectively. Interpretation Phaeochromocytoma–paraganglioma syndrome can be diagnosed reliably by an immunohistochemical procedure. SDHB, SDHC, and SDHD germline mutation testing is indicated only in patients with SDHB-negative tumours. SDHB immunohistochemistry on phaeochromocytomas and paragangliomas could improve the diagnosis of phaeochromocytoma–paraganglioma syndrome.

Our results demonstrate that SDHA immunohistochemistry on paraffin-embedded tumors can reveal the presence of SDHA germline mutations and allowed the identification of SDHA-related tumors in at least 3% of patients affected by apparently sporadic (para)sympathetic paragangliomas and pheochromocytomas.

Heterozygous fumarate hydratase (FH) germline mutations cause hereditary leiomyomatosis and renal cell cancer (HLRCC), an autosomal dominant syndrome characterized by multiple cutaneous piloleiomyomas, uterine leiomyomas and papillary type 2 renal cancer. The main objective of our study was to evaluate clinical and genetic data from families suspected of HLRCC on a nationwide level. All families referred for FH mutation analysis in the Netherlands were assessed. We performed FH sequence analysis and multiplex ligation-dependent probe amplification. Families with similar FH mutations were examined for haplotype sharing. In 14 out of 33 families, we identified 11 different pathogenic FH germline mutations, including 4 novel mutations and 1 whole-gene deletion. Clinical data were available for 35 FH mutation carriers. Cutaneous leiomyomas were present in all FH mutation carriers older than 40 years of age. Eleven out of 21 female FH mutation carriers underwent surgical treatment for symptomatic uterine leiomyomas at an average of 35 years. Two FH mutation carriers had papillary type 2 renal cancer and Wilms' tumour, respectively. We evaluated the relevance of our findings for clinical practice and have proposed clinical diagnostic criteria, indications for FH mutation analysis and recommendations for management.

Phaeochromocytomas and paragangliomas (PPGLs) are neural-crest-derived tumours of the sympathetic or parasympathetic nervous system that are often inherited and are genetically heterogeneous. Genetic testing is recommended for patients with these tumours and for family members of patients with hereditary forms of PPGLs. Due to the large number of susceptibility genes implicated in the diagnosis of inherited PPGLs, next-generation sequencing (NGS) technology is ideally suited for carrying out genetic screening of these individuals. This Consensus Statement, formulated by a study group comprised of experts in the field, proposes specific recommendations for the use of diagnostic NGS in hereditary PPGLs. In brief, the study group recommends target gene panels for screening of germ line DNA, technical adaptations to address different modes of disease transmission, orthogonal validation of NGS findings, standardized classification of variant pathogenicity and uniform reporting of the findings. The use of supplementary assays, to aid in the interpretation of the results, and sequencing of tumour DNA, for identification of somatic mutations, is encouraged. In addition, the study group launches an initiative to develop a gene-centric curated database of PPGL variants, with annual re-evaluation of variants of unknown significance by an expert group for purposes of reclassification and clinical guidance.

Funding Agencies|Cancer Prevention and Research Institute of Texas (CPRIT) [RP101202, RP57154]; Department of Defense [CDMRP W81XWH-12-1-0508]; Voelcker Fund; National Institutes of Health (NIH)s National Center for Research Resources; National Center for Advancing Translational Sciences [8UL1TR000149]; INSERM; French National Cancer Institute (INCA); Direction Generale de lOffre de Soins (DGOS); INCA [INCA-DGOS_8663]; European Union [633983]; Brazilian National Council for Scientific and Technological Development (CNPq); Cancer Research for PErsonalized Medicine (CARPEM); ERC Advanced Researcher Award

Background: Fumarate hydratase (HGNC approved gene symbol -FH), also known as fumarase, is an enzyme of the tricarboxylic acid (TCA) cycle, involved in fundamental cellular energy production. First described by Zinn et al in 1986, deficiency of FH results in early onset, severe encephalopathy. In 2002, the Multiple Leiomyoma Consortium identified heterozygous germline mutations of FH in patients with multiple cutaneous and uterine leiomyomas, (MCUL: OMIM 150800). In some families renal cell cancer also forms a component of the complex and as such has been described as hereditary leiomyomatosis and renal cell cancer (HLRCC: OMIM 605839). The identification of FH as a tumor suppressor was an unexpected finding and following the identification of subunits of succinate dehydrogenase in 2000 and 2001, was only the second description of the involvement of an enzyme of intermediary metabolism in tumorigenesis.