SDHB Loss Predicts Malignancy in Pheochromocytomas/Sympathethic Paragangliomas, but Not Through Hypoxia Signalling Abstract #246

Introduction: To date there is no reliable histopathological marker of malignancy for pheochromocytomas/sympathetic paragangliomas (PCC/PGL). It is well-known that PCC/PGL in the hereditary context of an SDHB germline mutation very often metastasize. The immunohistochemical loss of SDHB expression was recently shown to be a surrogate marker for the presence of an SDH germline mutation in PCC/PGL. SDHB loss is supposed to be tumorigenic via activation of hypoxia signals.
Aim(s): To clarify potential use of SDHB immunohistochemistry as a marker of malignancy in PCC/PGL and also its association with classic hypoxia signalling.
Materials and methods: The protein expression of SDHB, Hif-1alpha and its targets CA-9 and GLUT-1 was examined by immunohistochemistry using a tissue microarray containing a series of familial and sporadic tumors of 115 patients. The obtained results were correlated with survival data which were available for 66 patients.
Conference: 8th Annual ENETS Conference (2011)
Category: Basic
Presenting Author: Dr Anja M Schmitt

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