MEN1 and pancreatic neuroendocrine tumor: Hallmarks of NET G1/G2 are loss of chromosome 18, inactivation of CDKN1/APC, and gain of chromosomes 4, 5, and 14 in NET of the small intestine and inactivation of MEN1/chromosome 11, DAXX/ATR, and PTEN/TSC2 in pancreatic NET [34].