1. the absence of extrapancreatic disease,
2 .a patent superior mesenteric-portal vein confluence, and
3. no direct tumor extension to the celiac axis or superior mesenteric artery.

Patients whose tumors do not meet these criteria are not considered candidates for potentially curative surgery.

CT and MR imaging examinations are tailored to the pancreas, rather than being done as routine screening examinations. We rely on thin-section CT, preferably with helical scanning done during the early phase of intravenous contrast enhancement. MR imaging, when done with fast scanning and fat-suppressed sequences with and without intravenous contrast enhancement, provides similar information. There has been no conclusive evidence about which modality is better. The Radiology Diagnostic Oncology Group, using data obtained from conventional CT and MR imaging, currently recommends CT for the initial assessment of patients with pancreatic tumors, but MR imaging can be used when there is a contraindication (patient allergy) to contrast-enhanced CT.

Computed Tomography Techniques--specific techniques employed at M. D. Anderson Cancer Center for CT imaging of the pancreas

Computed Tomography Findings--major radiographic findings with CT imaging of pancreatic carcinoma

Differential Diagnosis--use of CT to distinguish between types of pancreatic masses

Vascular Involvement--radiographic assessment of the tumor-blood vessel relationship

Pathways of Tumor Infiltration--radiographic assessment of tumor spread

Helical CT Angiography--state-of-the-art assessment of pancreatic tumors

Endoscopic Retrograde Cholangioapancreatography (ERCP) and Endoscopic Ultrasound (EUS)

If a low-density mass is not seen on CT scans, despite the presence of extrahepatic biliary obstruction, patients should undergo ERCP and EUS. Diagnostic ERCP is used in the setting of extrahepatic biliary obstruction when CT or EUS fails to identify a neoplastic cause for biliary obstruction, or when Fine Needle Aspiration (FNA) under EUS guidance has been nondiagnostic. A malignant obstruction of the intrapancreatic portion of the common bile duct (CBD) is characterized by the presence of a stricture in both the intrapancreatic CBD and the pancreatic duct ("double-duct sign"). This often can be accurately differentiated from choledocholithiasis, and the long, smooth tapering stricture seen with chronic pancreatitis. Tissue diagnosis may be obtained at the time of ERCP. Finally, the absence of findings consistent with malignancy on ERCP combined with the absence of a low density mass on high-quality CT makes periampullary malignancy unlikely. ERCP may also be therapeautic; endoscopic biliary decompression is necessary in patients with symptoms of pruritus or cholangitis, and in patients with asymptomatic hyperbilirubinemia who are to be treated with chemoradition prior to surgery. Plastic stents (11.5 Fr.) are used in patients with potentially resectable disease, and expandable metal stents (10 mm) are preferred in patients with locally advanced (nonsurgical) disease.

EUS-guided FNA is performed in patients with unresectable disease (locally advanced or metastatic) and in patients with potentially resectable primary tumors who are candidates for protocol-based preoperative chemoradiation. EUS allows for real-time identification of the suspected malignancy at the time of FNA, which may lead to improved accuracy over CT-guided FNA. EUS-guided FNA is rapidly becoming the biospy technique of choice in patients who require cytologic confirmation of pancreatic malignancy. In addition, EUS can accurately assess the relationship of the primary neoplasm to adjacent vascular structures.