The possible mechanisms of cisplatin-induced SIADH are as follows: (1) cisplatin-induced vomiting/hypovolemia may stimulate AVP synthesis/secretion, (2) cisplatin may activate AVP neurons in the hypothalamus directly, and (3) continuous secretion of AVP into the portal vein in the external layer of the median eminence projected from the pPVN [26, 27]. Here, AVP is linked to inappropriate ADH syndrome.