An excess of fumarate is well-described in tumors and may be linked to germline mutations in fumarate hydratase (FH), a condition which predisposes to hereditary leiomyomatosis and renal cell cancer [71], but interestingly also evidences for a link with FH are reported in breast and bladder carcinomas [72]. The gene discussed is FH; the disease is urinary bladder carcinoma.