Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

Insulinomas are pancreatic neoplasms that can be radiologically characteriz ed typically because of their tendency to present intense and early contras t enhancement with a wash-out phenomenon. In this sense, we report an unusu al case of a hypovascular solid pancreatic insulinoma confirmed with surger y and pathologic analysis, in a patient with normal serum insulin levels. I n the two-phase helical CT, the mass behaved as a hypodense lesion with res pect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. P athologic examination demonstrated a hypercellular tumor with poor vascular ization of intervening stroma which showed prominent amyloid deposits.