15. Glucagonomas
Due to the vast number of symptoms a patient can develop, it can be hard for doctors to determine whether it’s pancreatic cancer or another type of tumor. If you’re suffering from a glucagonoma tumor it will secrete glucagon, which can increase blood sugar levels and mimic diabetes. A distinguishing symptom of this type of tumor is irritation of the tongue and corners of the mouth, as well as a rash called necrolytic migratory erythema. According to the American Cancer Society, the rash is red and blistery and is the number one reason patients with glucagonoma tumors see a doctor.