Impact of Pancreaticoduodenectomy on Remnant Pancreas Vascular Enhancement Patterns: Raising the Specter of Pancreatic Recovery

Abstract

Introduction: Pancreatic cancer is well recognized to cause changes in the non-tumoral pancreatic parenchyma. The aim of this investigation was to examine the impact of pancreaticoduodenectomy on postoperative pancreatic parenchymal enhancement patterns. Methods: Consecutive patients who underwent pancreaticoduodenectomy for IPMN or non-IPMN associated pancreatic adenocarcinoma were selected. ROIs were selected in the proximal pancreatic bod. The pancreatic values were normalized to the HU in aorta and porta vein. Median values with standard deviations were calculated and ratios were compared by two tailed Student’s t-testing. Results: A total of 85 patients were included (38 with adenocarcinoma, 47 with IPMN and IPMN associated cancer). No patients had chronic pancreatitis and 19% received neoadjuvant therapy. There was improvement in arterial pancreatic parenchymal enhancement postoperatively (0.33 to 0.44 normalized HU ratios, p<0.0001) with 63% of patients improving in arterial enhancement(0.85 ± 0.5 normalized HU ratio), and venous kinetic enhancement pattern (0.64 to 0.58, P=0.02). When patients were stratified into those who had normal vs abnormal kinetic enhancement preoperatively, no differences were seen in the postresection enhancement values (see Table). Among those with an abnormally enhancing gland preop, 85% had improvement, with significantly higher improvement than those with normal gland. Conclusions: After pancreaticoduodenectomy, there is a measurable improvement in pancreatic enhancement patterns on axial imaging. The improvement in the briskness of arterial enhancement is even more marked in those who have an abnormal parenchymal pattern preoperatively. These data suggest the possibility of some amount of parenchymal recovery for the remnant gland after pancreaticoduodenectomy.