No symptoms, at least not ones that can make me think about it. I was 170 lbs, diagnosed with diabetes, but no meds ( diet and excersise). Lost weight (150lbs) but my blood glucose and A1C did not change. Had a stroke and during a chest CT scan the mass showed. Now - 3 months after surgery (pNET debulking, gall bladder and spleen removed, part of my stomach resected and full hysterectomy) my 1AC was normal and blood glucose in norm.