A VIPoma -LRB- also known as PERSON@1 syndrome , after the physicians who first described it -RRB- is a rare -LRB- NUMBER@1 per NUMBER@2 per year -RRB- endocrine tumor , usually -LRB- about NUMBER@3 % -RRB- originating in the pancreas , that produces vasoactive intestinal peptide -LRB- VIP -RRB- .

A VIPoma -LRB- Pronounced `` V I P oma '' -RRB- -LRB- also called PERSON@1 syndrome after the doctors who first noticed it -RRB- , is a tumor that does not happen a lot -LRB- NUMBER@1 per NUMBER@2 per year -RRB- in the pancreasDorland 's Medical Dictionary .
