Surgical approach to insulinomas. Assessing the need for preoperative localization
J. L. Pasieka, M. K. McLeod, N. W. Thompson and R. E. Burney
Department of Surgery, University of Michigan, Ann Arbor 48109-0331.
The purpose of this study was to examine our experience with the diagnosis,
surgical approach, and outcomes of surgery for organic hyperinsulinemia in
the era of transhepatic venous sampling. During the period from 1978 to
1991, 50 patients were evaluated and treated for hyperinsulinemia at the
University of Michigan Medical Center, all of whom underwent preoperative
localization. Forty-one patients (82%) had solitary, benign tumors; four
(8%) had either multiple tumors or islet cell dysplasia; and five (10%) had
metastatic disease. Forty-seven patients underwent laparotomy, and the
source of the hyperinsulinemia was found in all patients. In three patients
(6%) preoperative localization did not accurately locate the tumor due to
technical difficulties with the completion of the studies. Overall,
computed tomography localized nine (26%) of 35 tumors. Angiography
accurately localized 18 (44%) of 41 tumors. Transhepatic venous sampling
localized 34 (94%) of 36 tumors, and was essential to successful surgical
treatment in 15 patients. Compared with angiography, transhepatic venous
sampling was a more accurate method of localization and should be performed
in all patients in whom computed tomography and visceral angiography do not
clearly identify the site of disease. Preoperative localization plays a
critical role in the surgical treatment of patients with organic
hyperinsulinemia and eliminates the need for blind pancreatic resection.
