FH and pheochromocytoma: The sporadic loss of FH or transcriptional downregulation of FH was found in various cancers, such as pheochromocytomas, paragangliomas, neuroblastomas, adrenocortical carcinoma, ependymoma, osteosarcoma, bladder cancer, breast cancer, glioma, colorectal cancer, and testicular cancers [38,39,40,41,42,43].