IGF2 and Hypoglycemia: However, in many of the cases of what is called tumor-induced hypoglycemia the etiological agent of hypoglycemia is not an insulin but its structurally similar polypeptide, somatomedin A also called insulin-like growth factor II (IGF-II), and the hypoglycemia is referred to as nonislet cell tumor hypoglycemia (NICTH) 2.