Novel Variant Associated to Bilateral Phaeochromocytoma with an Uncommon Clinical Presentation.

Phaeochromocytomas and paragangliomas are rare catecholamine-secreting tumours arising from the adrenal medulla or sympathetic paraganglia. It is known that 20-30% of all cases occur as a result of germline variants in several well known genes. The gene was recently identified as a new phaeochromocytoma susceptibility gene. However, until a larger sample of cases is available, the prevalence, genotype-phenotype correlation, and a clear predominant biochemical pattern of -related PCC, remain to be defined. We present a woman with the pathogenic variant c.86delG (p.Arg29Leus52) in the gene, which has not been previously reported, associated to a bilateral phaeochromocytoma, with an uncommon initial clinical presentation and a biochemical profile that is distinctly adrenergic. Her two young children carry the same variant and are, at present, disease-free. Physicians should be aware that phaeochromocytoma can manifest in an atypical manner, as with episodic hypotension, mainly if the symptoms have no obvious aetiology and they worsen over time. This case also supports the presence of a predominant adrenaline secreting pattern in -positive tumours, as well as the need to consider multigene panel testing in patients with bilateral phaeochromocytomas.