A case of pancreatic cholera (Verner-Morrison syndrome) associated with a pancreatic endocrine tumor and hepatic metastases is presented. VIP and HPP plasma levels, initially elevated, were accurately followed in various conditions: during corticosteroid therapy, after pancreatic tumor excision, during and after streptozotocin therapy (1.5 g/m2) by repeated intraarterial route). Only streptozotocin therapy resulted in a reduction of the stool volume with concomitant decrease in VIP plasma levels. However, the size of the hepatic metastases was unchanged and HPP plasma levels remained elevated. It is suggested that VIP represents the tumoral secretion and HPP a marker of the residual malignant tissue.