Nonsurgical diagnosis of pancreatic mass.

Because of recent advances made in various diagnostic procedures, it has become easier to diagnose cancer of the head of the pancreas. Chronic pancreatitis, however, may show morphologic mass findings similar to pancreatic cancer. Twenty-three patients with a pancreatic head "mass," identified through surgical exploration, have been reviewed retrospectively with regard to differential diagnosis by comparing the preoperative findings of duodenoscopy, endoscopic retrograde pancreatography (ERP), endoscopic retrograde cholangiography (ERC), and percutaneous transhepatic cholangiography (PTC). Emphasizing the findings, value, and limitations of each procedure, we used simple morphologic criteria for our differential diagnosis. Duodenoscopic findings gave information for accurate diagnosis in 66%, ERP was correct in 50%, and ERC in 88%. PTC in 88%. PTC was helpful in establishing the correct diagnosis in 90%. This study clarifies some technical and practical aspects of these procedures. We believe duodenoscopy must be used more often for direct histologic study, cytology, and needle biopsy in addition to ductal visualization in a pancreatic head mass. PTC is recommended more strongly for use in establishing the correct diagnosis of a pancreatic head "mass."