Pheochromocytomas and paragangliomas are tumors arising from chromaffin cells. Pheochromocytoma and paraganglioma can occur as a part of genetic syndromes – familial paragangliomas (SDH genes, SDHAF2 gene), von Hippel-Lindau syndrome (VHL gene), multiple endocrine neoplasia type 2 (RET gene), and neurofibromatosis type 1 (NF1 gene).