Specifically, about 42% of SDHB mutation carriers develop pheochromocytomas or paragangliomas by the age of 70 (Jochmanova et al. 2017, Rijken et al. 2017), and up to almost 60% of the tumors have been reported to metastasize (Jochmanova et al. 2017). This evidence concerns the gene SDHB and hereditary pheochromocytoma-paraganglioma.