Preoperative Localization Of Insulinomas Research Articles

Percutaneous transhepatic portal vein catheterization for localization of insulinoma.

AbstractThe experiences of percutaneous transhepatic catheterization of the portal vein and immunoassay for insulin of blood samples taken from the splenic and portal veins for localization of isulinoma are reported. This method was carried out in 17 patients, including 11 cases of clinically diagnosed insulinoma (with pathological proof in 9), 2 patients with residual symptoms following previous excision of an insulinoma, and 4 cases eventually proven not to be insulinomas. The results showed that a high value of insulin was present at or near the site of the tumor in 8 single benign insulinomas, while a sustained elevation of plasma insulin throughout the course of the veins was seen in a patient with malignant insulinoma and widespread metastases. The insulin values were not elevated in the 4 patients without insulinomas. Although this method is useful in preoperative localization of insulinomas, it cannot replace thorough and careful palpation of the pancreas at the time of operation.

Localization of Occult Insulinoma by Super-Selective Pancreatic Venous Sampling for Insulin Assay through Percutaneous Transhepatic Catheterization

Preoperative localization of insulinomas by arteriography is successful only 66% of the time. With small tumors, intraoperative localization is usually unsuccessful also. Because surgical morbidity and mortality are increased greatly when major, blind, pancreatic resections or reoperations are performed, additional preoperative localization procedures are needed. We now report the successful localization of an occult insulinoma by means of blood sampling for insulin radioimmunoassay, obtained by selective pancreatic vein sampling through percutaneous transhepatic catheterization. Our patient had symptoms of fasting hypoglycemia for 11 months. Routine studies were normal and two fasting plasma glucose concentrations were 34 and 16 mg/dl to correspond with insulin values of 33 and 75 μU/ml. Celiac arteriography was normal. Percutaneous transhepatic portal and pancreatic venous catheterization revealed insulin concentrations (μU/ml) of between 23 and 36 in portal and splenic veins, 17 in the short, gastric vein, 17 in the dorsal pancreatic vein, 19 in the superior, mesenteric vein, and 61 and 288 in two pancreatic magna veins draining the tail. An insulinoma of 2 × 3 cm was resected from the tail. On the basis of our experience with this patient, it is clear that selective venous sampling may facilitate the localization of occult insulinomas at surgery and thereby avoid extensive, blind, pancreatic resections and the need for reoperation.