The majority of these reported cases are composite pheochromocytoma-ganglioneuroma and comprised an association with MEN2 (20–24), VHL (25), NF1 (26–28) and, most recently (29), one case of a new MAX gene heterozygous variant, c.299G>C (p.Arg100Pro, NM_002382). Here, MAX is linked to hereditary pheochromocytoma-paraganglioma.