according to the more recent views , chemodectoma or paraganglioma ( chromaffine or non-chromaffine , functionally active or silent ) and pheochromocytoma ( functionally active or silent , adrenal or extra-adrenal ) constitute a group of tumors sharing the same tissue matrix , namely paragangliar cells .
C0030421
paraganglioma
C0031511
pheochromocytoma