Attempted retrograde cannulation of the ampulla: a probable cause of mass in the pancreas.

Two patients developed a focal mass in the head of the pancreas presumably following attempted endoscopic retrograde cholangiopancreatography (ERCP). These lesions grossly mimicked carcinomas of the pancreas. In one case a radical pancreatoduodenectomy was performed because of the misleading gross findings. A focal mass in the pancreas following ERCP may develop due to asymptomatic pancreatitis caused by the procedure.