Perfusion CT is useful for the differential diagnosis of autoimmune pancreatitis from pancreatic cancer

Abstract

Radiological findings of autoimmune pancreatitis (AIP) are sometimes similar to those of pancreatic cancer (PC). The aim of this study was to clarify the utility of perfusion computed tomography (CT) for the differential diagnosis of AIP from PC. Perfusion CT was performed in 12 patients with AIP and 22 patients with PC. All AIP patients were diagnosed as type 1. Parameters including pancreatic volumetric blood flow F_V, volume of distribution V_D and blood perfusion pattern R² were determined from a single-compartment kinetic model. Pancreatic F_V values of the 12 AIP patients (81.3/min) were significantly higher than those of 22 PC patients (19.3/min, p=0.0005). Pancreatic V_D values of the AIP patients (28.8) were significantly lower than those of the PC patients (93.6, p=0.0084). Moreover, pancreatic R² values of the AIP patients (0.659) were significantly higher than those of the PC patients (0.250, p<0.0001). Perfusion CT is useful to distinguish AIP from PC by the comparison of the parameters of blood flow, distribution and blood perfusion pattern.