Pilot Study Using Secretin and Iodinated Intravenous Contrast and 64-Channel CT in Patients at High Risk for Pancreatic Adenocarcinoma

Pancreatic cancer is the fourth most common cause of cancer death in the US. Because patients with pancreatic cancer rarely presents with disease specific symptoms until late in the course of the disease, identifying and developing surveillance strategies for early detection of asymptomatic pancreatic cancer is critical. EUS and fine needle aspirate (FNA) are currently the most accurate non-operative methods of establishing the presence or absence of pancreatic cancer.

The CT findings of pancreatic cancer include an attenuation difference between the pancreatic mass and the surrounding pancreatic parenchyma, pancreatic ductal dilation and cutoff, disruption of the normal fatty marbling of the pancreatic parenchyma, rounding of the inferior margin of the posterior head of the pancreas, atrophy of the proximal gland, and signs of locally advanced or distant disease. In a case-controlled retrospective review of pancreatic cancers missed at CT prior to clinical presentation at the Mayo Clinic, Gangi et al found that CT findings definite or suspicious for pancreatic cancer were present in 50% of scans obtained up to 18 months before the clinical diagnosis of pancreatic cancer. Pancreatic duct dilation and cutoff were early CT findings indicating tumor presence, and were associated with near-perfect and substantial interobserver agreement. Consequently, early pancreatic neoplasms likely result in at least partial occlusion of the duct, leading to subsequent ductal dilation.

We hypothesize that increased production of the pancreatic juice distends the otherwise small caliber pancreatic duct, and accentuate the secondary sign of pancreatic duct obstruction by a small pancreatic mass. The investigators will be able to take advantage of this physiologic effect of secretin, by obtaining multi-planar scans with isotropic resolution using a 64-channel CT system.

Secretin is a safe agent that increases pancreatic exocrine secretion. Intravenously administered secretin increases the pancreatic juice secretion, and magnetic resonance or CT scan obtained after secretin has been shown to improve visualization of the pancreatic duct.

Day 1: Patient will fast 4 hours prior to the study. 1 L of water is given by mouth as an oral contrast material 30 minutes prior to the study. After placing an angiocath in the antecubital fossa, the patient will be placed in a supine position on the CT scanner.