Functioning Mediastinal Paraganglioma Associated with a Germline Mutation of von Hippel-Lindau Gene.

We report the case of a 21-year old woman presenting with high blood pressure and raised normetanephrine levels. Indium-111-pentetreotide single photon-emission computed tomography with computed tomography (SPECT/CT) and 2-deoxy-2-[fluorine-18]fluoro-d-glucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging showing isolated tracer-uptake by a 2 cm tumor close to the costovertebral angle of the third thoracic vertebra. Thoracic surgery led to normalization of normetanephrine levels. Histological findings were consistent with the presence of a paraganglioma. Mutations in , , , , , , , , , , , and were absent, but a heterozygous missense mutation, c.311G > T, was found in exon 1 of the von Hippel-Lindau gene, , resulting in a glycine to valine substitution in the VHL protein at position 104, p.Gly104Val. This same mutation was found in both the mother and the 17-year old sister in whom a small retinal hemangioblastoma was also found. We diagnose an unusual functional mediastinal paraganglioma in this young patient with a germline gene mutation, a mutation previously described as inducing polycythemia and/or pheochromocytoma but not paraganglioma or retinal hemangioblastoma.