Background: The need for preoperative localization of an insulinoma is still under discussion. The aim of the present study was to determine the usefulness of preoperative localization of the tumour, to investigate the operative risk and to analyse the long-term course.
Patients and methods: The sensitivity of the diagnostic workup was investigated prospectively in 26 patients operated on between 1. 9. 1985 and 31. 8. 1994 for hyperinsulinism at the surgical department of the university hospital in Mainz.
Results: In the case of solitary adenomas the sensitivity of preoperative sonography was 43%, that of CT 57%, and that of angiography 85%. Intraoperatively, all solitary adenomas were palpable and were to be seen at sonography. In a patient with multiple adenomas, only one tumour was seen sonographically. The postoperative course was unremarkable in 18 out of 27 operations on the pancreas; two patients died later. After a mean follow-up of 51 months, all patients were free of hypoglycaemic attacks.
Conclusions: The results show that localization of the tumour prior to the first operation is no longer necessary in patients with no MEN syndrome. In the presence of the latter, however, it is recommended despite its low sensitivity. Although a permanent cure is possible with surgery, the morbidity of the operation is not negligible.