Pancreatic Cancer: Comparison of Two Series of Dual-phase Helical CT in Detection of Tumor and in Assessing Vascular Invasion

Abstract

Purpose: To compare the clinical utility of two series of dual-phase helical CT scans of the pancreas for tumor detectability and for the evaluation of vascular invasion. Materials and Methods: Two series of dual-phase helical CT scans of the pancreas were performed in 49 patients with pancreatic adenocarcinoma proven by pathology (n=21) and by clinical findings (n=28). The first series, in 24 patients, was obtained with a 45-sec (pancreatic phase) and an 80-sec delay (hepatic phase), and for the second series, in 25 patients, the corresponding delay times were 35 and 75 secs. A total of 120 ml non-ionic contrast media was injected of a speed of 3 ml/sec. Tumor conspicuity for each phase was assessed by measuring the attenuation number of the pancreatic mass and of normal pancreas. Enhancement of the celiac axis (CA), superior mesenteric artery (SMA), and superior mesenteric and portal veins was assessed by measuring the attenuation number of each phase. Results: A comparison of the first and second series revealed no statistically significant tumor conspicuity. Enhancement of the celiac axis and superior mesenteric artery was better on scans obtained at 35-sec/75-sec delay (CA 254 ; p