• David Taïeb, Chunzhang Yang, Blandine Delenne, Zhengping Zhuang, Anne Barlier, Fréderic Sebag, and Karel Pacak.
• Department of Nuclear Medicine, La Timone University Hospital, Centre Européen de Recherche en Imagerie Médicale, Aix-Marseille University, 13005 Marseille, France.
• J. Clin. Endocrinol. Metab. 2013 May 1; 98 (5): E908-13.

ContextMolecular genetic research has so far resulted in the identification of 10 well-characterized susceptibility genes for hereditary pheochromocytoma (PHEO) or paraganglioma (PGL). Recently, a new syndrome characterized by multiple PGLs and somatostatinomas associated with congenital polycythemia due to somatic mutations in HIF2A has been reported.ObjectiveThe aim of the study was to define the genetic defect in a new case of bilateral PHEO and multiple PGLs associated with congenital polycythemia.PatientA female patient presented with neonatal polycythemia (treated by phlebotomies, 1 session approximately every 4 mo), mildly enlarged cerebral ventricles, and bilateral PHEO and multiple PGLs. There was no family history of any neuroendocrine tumor or polycythemia. Surgical removal of the tumors only temporarily normalized plasma erythropoietin (Epo) levels and discontinued phlebotomies. No germline mutations were initially detected in the SDHB, SDHC, SDHD, VHL, and PHD2 genes, known to be associated with polycythemia. The PHEOs presented with a typical noradrenergic biochemical phenotype.ResultsA heterozygous missense mutation (c.1589C>T) was identified in exon 12 of HIF2A, resulting in an alanine 530 substitution in the HIF-2α protein with valine (A530V). This somatic mutation was detected in the tissue from 1 PHEO and 1 PGL, with no HIF2A germline mutation found. This mutation led to stabilization of HIF-2α and hence a gain-of-function phenotype, as in previously published studies.ConclusionThis case represents the first association of a somatic HIF2A gain-of-function mutation with PHEO and congenital polycythemia, and it alerts physicians to perform proper genetic screening in patients presenting with multiple norepinephrine-producing PHEOs and polycythemia. This report also extends the previous findings of a new syndrome of only multiple PGLs, somatostatinomas, and polycythemia to multiple PHEOs.

32 keywords...

hide…