Gastrinomas may occur as single tumors or as multiple, small tumors. About one-half to two-thirds of single gastrinomas are malignant tumors that most commonly spread to the liver and lymph nodes near the pancreas and small bowel. Nearly 25 percent of patients with gastrinomas have multiple tumors as pa of a condition called multiple endocrine neoplasia type I (MEN I). MEN I patients have tumors in their pituitary gland and parathyroid glands in addition to tumors of the pancreas.

Ans. B: Post-prandial abdominal pain, weight loss, chronic mesenteric vessel occlusion The 3 aeries supplying the gut are the celiac, superior mesenteric, and inferior mesenteric. Unless significant stenoses or actual occlusion of 2 of the 3 vessels is present, efficient collateral circulation between the celiac and superior mesenteric aeries (i.e., the pancreaticoduodenal arcades) and the superior and inferior mesenteric aeries (i.e., the meandering mesenteric aery) ensures that blood flow to the gut generally is adequate. The internal iliac aeries also may be an impoant source of collateral hindgut and midgut perfusion in the presence of inferior mesenteric aerial occlusion. The most common cause of abdominal angina is atherosclerotic vascular disease (chronic process). The occlusive process commonly involves the ostia and a few proximal centimeters of the mesenteric vessels. Abdominal angina is defined as the postprandial pain that occurs in individuals with sufficient mesenteric vascular occlusive disease such that blood flow cannot increase enough to meet visceral demands. Soon, patients associate eating with pain and develop a characteristic fear of food (i.e., sitophobia) or food-avoidance behavior. Repoed weight loss averages 5-6 kg.