VIP and carcinoid syndrome: OCT and LAN (both immediate-release and long-acting formulations) are the standard of care for functioning and non-functioning NETs [182,188] to control severe symptoms (diarrhea and flushing, carcinoid syndromes) associated with hypersecretion of serotonin, and pancreatic islet cell hormonal-secretory syndromes sustained by gastrin, glucagon, insulin, vasoactive intestinal peptide (VIP), and parathyroid hormone-related peptide [189].