Succinate Dehydrogenase Subunit B (SDHB) Immunohistochemistry Should Not Replace Clinical Genetic Testing for SDHx Mutations in Patients with Pheochromocytoma and Paraganglioma Abstract #838

Introduction: Mutations in any of the subunits of the succinate dehydrogenase (SDH) complex predispose to PCC/PGL. Knowing the germline mutation is important for surveillance for recurrence, metastatic disease or more primary tumors and for screening affected family members. Expression of SDHB protein by immunohistochemistry (IHC) has been proposed as a surrogate marker for SDHx mutation status, with absent or decreased expression of SDHB suggesting the presence of a germline SDHB mutation or disruption of the SDH complex by mutation in another subunit.
Aim(s): To evaluate the effectiveness of SDHB IHC in predicting SDHx germline mutation status.
Materials and methods: We performed a retrospective review of the pathology reports between 2011-13 which included SDHB IHC on PCC/PGLs from patients with clinical genetic testing who either tested positive for SDHx germline mutation or had no identified mutation.
Conference: 11th Annual ENETS Conference (2014)
Category: Non digestive NETs (bronchial, MTC, pheochromocytoma)
Presenting Author: Lauren Fishbein

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Presenting Author: Mr João Vinagre
Authors: Vinagre J, Preto J, Soares P, Lopes J M, ...
Keywords: PETs SDH LOH
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