Vasoactive intestinal peptide secreting tumors of childhood.

A 2-year-old boy with failure to thrive, watery diarrhea, abdominal distention, hypokalemia, metabolic acidosis, and episodes of hypertension and sweating was found to have a calcified right lower quadrant mass. Blood levels of vasoactive intestinal peptide (VIP) and norepinephrine (NE) were elevated. Presurgical management with phenoxybenzamine hydrochloride and metyrosine was associated with an absence of expected postoperative hypotension, and resection of a benign ganglioneuroma resulted in prompt relief of all symptoms and return to normal of VIP and NE levels. Evidence supports the theory that VIP is the substance responsible for the diarrhea that accompanies some neural crest tumors.