Pre‐ and intraoperative localization of insulinomas: Report of 22 observations

Abstract
From a retrospective analysis of 22 cases of pancreatic insulinoma operated in our center, we have determined the predictive value of various pre‐ and intraoperative localization procedures. In 18 patients, solitary insulinomas were localized by selective arteriography (SA) in 55.5% of cases, by transhepatic catheterization with pancreatic venous sampling (THVS) in 64% of cases, but by ultrasonography (US) and computed tomography (CT) in only 11% of cases. The combination of SA and THVS allowed the preoperative localization of the tumor in 83% of cases. Intraoperative palpation, ultrasonography, and blood glucose monitoring localized a single tumor in all cases.When the insulinomas were multiple, the various preoperative investigations were not reliable. In the 4 cases of multiple insulinoma, various investigations (SA, US, CT, THVS) localized only 8 (28%) tumors of 28. Intraoperative palpation was also unreliable. Only intraoperative ultrasonography and continuous blood glucose monitoring localizeall multiple tumors (the diameter of the smallest tumor was 4 mm). These 2 intraoperative investigations are now the procedures of choice for the detection of small pancreatic insulinomas.