I've developed islet cell carcinoma. What should I be watching out for in the future?

Difficult to say. Islet cell tumors are rare forms of cancer that arise in the endocrine tissues of the pancreas. They can secrete a variety of hormones, including insulin, glucagon, gastrin, and vasoactive intestinal peptide, resulting in a myriad of clinical syndromes. However, the majority are not associated with a hormonal syndrome, and therefore, yours may have been detected incidentally. I need more info.