The disease belongs to APUDoma. It is caused by non-beta islet cells secreting large amounts of vasoactive intestinal peptide, which strongly stimulates small intestine secretion and activates adenylate cyclase in the intestinal mucosa, leading to an increase in cAMP. This results in the movement of Cl^-, Na⁺, and water from the villous epithelial cells of the jejunal mucosa into the intestinal lumen, along with reduced K⁺ absorption, causing watery diarrhea, hypokalemia, and achlorhydria. Hence, it is also known as pancreatic cholera (WDHA). The tumors are benign in 40% of cases, malignant in 40%, and diffuse non-beta cell hyperplasia accounts for 20%.

bubble_chart Clinical Manifestations

Cholera-like watery diarrhea, initially intermittent, later persistent, with a prolonged course (3-15 years). Chronic severe watery diarrhea can lead to lack of strength, drowsiness, and weight loss. The watery diarrhea results in significant electrolyte loss, causing severe hypokalemia and hypomagnesemia, leading to hand and foot convulsions, as well as damage to the myocardium and kidneys. More than half of patients exhibit achlorhydria or hypochlorhydria, hypercalcemia, and urticaria-like skin changes. 80% are accompanied by diabetes.

[Auxiliary Examination]

1. Selective stirred pulse angiography can detect pancreatic islet tumors in one-third of cases.
2. 75Se-methionine pancreatic scanning can reveal lesions in polypeptide-secreting tumors due to increased methionine uptake.
3. Plasma vasoactive intestinal peptide (VIP) levels are elevated (normal average is 50 pg/ml).

bubble_chart Treatment Measures

1. Surgical treatment

Preoperative correction of typical edema and electrolyte imbalances is necessary. Half of pancreatic cholera cases are caused by benign islet cell or ganglioneuromas, so total pancreatectomy should be performed. If the pancreas appears normal during exploration, partial pancreatectomy is performed first. If pathological examination confirms non-beta cell hyperplasia, total pancreatectomy is then carried out. For malignant tumors with metastasis, tumor resection can also alleviate symptoms. If surgical exploration yields negative results, other areas should be investigated.

Suitable for unresectable malignant tumors. High-dose adrenal corticosteroids or local stirred pulse perfusion with streptozotocin can be used to relieve symptoms. Indomethacin treatment (75mg/day) has also shown some efficacy in reducing diarrhea and improving blood potassium levels.