Conditions that may cause SIAD include: ectopic ADH secretion by malignant tumor cells, for example, small cell lung cancer; increased production of ADH-like substances by the hypothalamus, secondary to trauma, infection, or tumors; infectious lung disease, including tuberculosis, pneumonia, and fungal infection, etc; and secretion of ADH stimulated by drugs, including cytotoxic drugs, anesthetics, and interferons.[7] However, few cases of vasopressin-producing pNETs leading to SIAD have been reported so far.[8]. Here, AVP is linked to small cell lung carcinoma.