Tumors. About 40% of islet cell tumors originate from a î² cell, secrete insulin (insulinoma), and can cause fasting hypoglycemia. î²-cell tumors are more common in patients < 40 years of age. About 60% of islet cell tumors originate from non-î²-cell elements and tend to occur in patients > 40 years of age. Non-î²-cell tumors are somewhat more likely to be malignant. Most islet cell tumors secrete pancreatic polypeptide, the clinical significance of which is unknown. Gastrin is secreted by many non–î²-cell tumors (increased gastrin secretion in men 1 also often originates from the duodenum). Increased gastrin secretion increases gastric acid, which may inactivate pancreatic lipase, leading to diarrhea and steatorrhea. Increased gastrin secretion also leads to peptic ulcers in > 50% of men 1 patients. Usually the ulcers are multiple or atypical in location, and often bleed, perforate, or become obstructed. Peptic ulcer disease may be intractable and complicated (zollinger-ellison syndrome—see tumors of the gi tract: zollinger-ellison syndrome). real viagra without a prescription viagra for sale buy viagra buy viagra generic viagra buy cheap viagra viagra without a doctor prescription buy cheap viagra buy viagra online cheap viagra Among patients presenting with zollinger-ellison syndrome, 20 to 60% have men 1. A severe secretory diarrhea can develop and cause fluid and electrolyte depletion with non–î²-cell tumors. This complex, referred to as the watery diarrhea, hypokalemia, and achlorhydria syndrome (wdha; pancreatic cholera—see tumors of the gi tract: vipoma), has been ascribed to vasoactive intestinal polypeptide, although other intestinal hormones or secretagogues (including prostaglandins) may contribute. Hypersecretion of glucagon, somatostatin, chromogranin, or calcitonin, ectopic secretion of acth (causing cushing's syndrome), and hypersecretion of growth hormone–releasing hormone (causing acromegaly) sometimes occur in non–î²-cell tumors. All of these are rare in men 1. Nonfunctioning pancreatic tumors also occur in patients with men 1 and may be the most common type of pancreatoduodenal tumor in men 1. The size of the nonfunctioning tumor correlates with risk of metastasis and death. Pituitary pituitary tumors occur in 15 to 42% of men 1 patients. From 25 to 90% are prolactinomas. About 25% of pituitary tumors secrete growth hormone or growth hormone and prolactin. Excess prolactin may cause galactorrhea (see pituitary disorders: galactorrhea), and excess growth hormone causes acromegaly clinically indistinguishable from sporadically occurring acromegaly. About 3% of tumors secrete acth, producing cushing's disease. Most of the remainder are nonfunctional. Local tumor expansion may cause visual disturbance, headache, and hypopituitarism. Pituitary tumors in men 1 patients appear to be larger and behave more aggressively than sporadic pituitary tumors. Other manifestations see also: list of conditions associa. viagra reviews young men