International initiative for a curated SDHB variant database improving the diagnosis of hereditary paraganglioma and pheochromocytoma

Adrenal gland diseases; Databases; Genetic variationEnfermedades de las glándulas suprarrenales; Bases de datos; Variación genéticaMalalties de les glàndules suprarenals; Bases de dades; Variació genèticaBackground SDHB is one of the major genes predisposing to paraganglioma/pheochromocytoma (PPGL). Identifying pathogenic SDHB variants in patients with PPGL is essential to the management of patients and relatives due to the increased risk of recurrences, metastases and the emergence of non-PPGL tumours. In this context, the ‘NGS and PPGL (NGSnPPGL) Study Group’ initiated an international effort to collect, annotate and classify SDHB variants and to provide an accurate, expert-curated and freely available SDHB variant database. Methods A total of 223 distinct SDHB variants from 737 patients were collected worldwide. Using multiple criteria, each variant was first classified according to a 5-tier grouping based on American College of Medical Genetics and NGSnPPGL standardised recommendations and was then manually reviewed by a panel of experts in the field. Results This multistep process resulted in 23 benign/likely benign, 149 pathogenic/likely pathogenic variants and 51 variants of unknown significance (VUS). Expert curation reduced by half the number of variants initially classified as VUS. Variant classifications are publicly accessible via the Leiden Open Variation Database system (https://databases.lovd.nl/shared/genes/SDHB). Conclusion This international initiative by a panel of experts allowed us to establish a consensus classification for 223 SDHB variants that should be used as a routine tool by geneticists in charge of PPGL laboratory diagnosis. This accurate classification of SDHB genetic variants will help to clarify the diagnosis of hereditary PPGL and to improve the clinical care of patients and relatives with PPGL.This work was supported in part by a salary grant to NB from Cancer Research for PErsonalized Medicine (CARPEM). ERM acknowledges funding from the European Research Council (Advanced Researcher Award), NIHR (Senior Investigator Award and Cambridge NIHR Biomedical Research Centre) and Cancer Research UK Cambridge Cancer Centre. The University of Cambridge has received salary support in respect of ERM from the NHS in the East of England through the Clinical Academic Reserve. PLD receives support from the National Institutes of Health (NIH)-National Institute of General Medical Science (NIGMS) GM114102, NIH-National Center for Advancing Translational Science (NCATS) Clinical Translational Science Award (CTSA) UL1 TR001120 and UL1 TR002645, the Mays Cancer Center NIH-National Cancer Institute (NCI) P30 CA54174, Alex’s Lemonade Childhood Foundation, with support from Northwest Mutual and Flashes of Hope, and University of Texas Health SystemSTARS Award. RAT holds a Miguel Servet-I research contract by Institute of Health Carlos III (ISCIII) of the Ministry of Economy (CP17/00199) and Competitiveness; is supported by an Olga Torres Foundation Emerging researcher grant and by the Swiss Bridge Award for cancer immunotherapy research; and received research grants from BeiGene, Novartis and AstraZeneca. Cancer Genetics, Kolling Institute, Sydney acknowledges support from the Hillcrest Foundation (Perpetual Trustees). JPB in Leiden, The Netherlands acknowledges support from the Paradifference Foundation. MR is supported by the Instituto de Salud Carlos III (ISCIII), Acción Estratégica en Salud, cofounded by FEDER (grant number PI17/01796)

International initiative for a curated SDHB variant database improving the diagnosis of hereditary paraganglioma and pheochromocytoma

Funder: Cancer Research UK Cambridge Cancer CentreBackground: SDHB is one of the major genes predisposing to paraganglioma/pheochromocytoma (PPGL). Identifying pathogenic SDHB variants in patients with PPGL is essential to the management of patients and relatives due to the increased risk of recurrences, metastases and the emergence of non-PPGL tumours. In this context, the ‘NGS and PPGL (NGSnPPGL) Study Group’ initiated an international effort to collect, annotate and classify SDHB variants and to provide an accurate, expert-curated and freely available SDHB variant database. Methods: A total of 223 distinct SDHB variants from 737 patients were collected worldwide. Using multiple criteria, each variant was first classified according to a 5-tier grouping based on American College of Medical Genetics and NGSnPPGL standardised recommendations and was then manually reviewed by a panel of experts in the field. Results: This multistep process resulted in 23 benign/likely benign, 149 pathogenic/likely pathogenic variants and 51 variants of unknown significance (VUS). Expert curation reduced by half the number of variants initially classified as VUS. Variant classifications are publicly accessible via the Leiden Open Variation Database system (https://databases.lovd.nl/shared/genes/SDHB). Conclusion: This international initiative by a panel of experts allowed us to establish a consensus classification for 223 SDHB variants that should be used as a routine tool by geneticists in charge of PPGL laboratory diagnosis. This accurate classification of SDHB genetic variants will help to clarify the diagnosis of hereditary PPGL and to improve the clinical care of patients and relatives with PPGL

Positive impact of genetic test on the management and outcome of patients with paraganglioma and/or pheochromocytoma

International audienceOC5.1Positive impact of genetic test on the management and outcome of patients with paraganglioma and/or pheochromocytomaContextParagangliomas and pheochromocytomas (PPGL) are rare neuroendocrine tumors, characterized by a strong genetic component. Indeed, up to 40% of patients carry a germline mutation in a PPGL susceptibility gene. In accordance with the international recommendations, genotyping of PPGL susceptibility genes is therefore proposed to all patients with PPGL, but it has actually never beenshown whether the identification of a germline mutation in one PPGL susceptibility gene changes the outcome of mutation-carriers.ObjectiveOur objective was to evaluate how a positive genetic test impacts the management and outcome of propositus patients with PPGL carrying a germline mutation in one of the four major PPGL susceptibility genes (SDHB, SDHD, SDHC and VHL).DesignWe performed a multicentric retrospective study on 221 propositus carrying a SDHB, SDHD, SDHC or VHL germline mutation and followed in 24 French clinical centers of the Group of Endocrine Tumors and/or the COMETE network. Patients were divided into two groups: Genetic patients, who were informed of their genetic status within the year following the first PPGL diagnosis, and Historic patients who only benefited from the genetic test several years after initial PPGL diagnosis.ResultsCompared to Historic patients, Genetic patients had a better follow-up, with a higher number of examinations and a reduced number of patients lost to follow-up (9.6% versus 72%). During follow-up, smaller (18.7 mm versus 27.6, PZ0.0128) new PPGL and metastases as well as lower metastatic spread were observed in Genetic patients. Importantly, these differences were reversed in the Historic cohort after genetic testing. Genetic patients who developed metachronous metastases had a better 5-year survival than Historic ones (PZ0.0127).ConclusionAltogether our study clearly shows the positive impact of the identification of an SDHx or VHL mutation in the management, clinical outcome and survival of patients with PPGL. It reveals, for the first time, the clinical benefits of the practice of oncogenetics for patients with a rare cancer and strongly strengthens the recommendations of the Endocrine Society to consider PPGL genetic testingin all patients affected by PPGL.DOI: 10.1530/endoabs.63.OC5.