Glucagonomas are rare tumors that arise from thepancreatic islet cell of Langerhans. Because of theuncommon occurrence of these tumors, the naturalhistory is not well defined and has largely been basedon case reports or small series. Less than 250 casesof glucagonomas have been reported in the Englishliterature. To our knowledge, the largest single institutionalexperience is from the Mayo Clinic where 21 cases were reported (1). We report one of thelargest series of 12 patients with a diagnosis ofglucagonomas treated at our institution.