Important clues to the diagnosis of pancreatic cancer.

The incidence of pancreatic carcinoma is recently increasing but the prognosis remains extremely poor. Widespread awareness of important clues to the diagnosis is particularly important to improve the prognosis. Dilatation of the main pancreatic duct on ultrasonograms and/or CT scans, hyperamylasemia incidentally found during routine blood examinations, and recent onset diabetes mellitus must lead to thorough imaging studies of the pancreas. Death from pancreatic carcinoma occurs in 0.2-1.9% of all diabetic patients, being more than 300 times frequent compared to general population. Diabetes may be the only clinical sign of pancreatic carcinoma in some patients. In our recent study, of 163 diabetic patients selected by several criteria who underwent ERCP screening, 12 patients (7.4%) proved to have pancreatic carcinoma. The prevalence of pancreatic carcinoma was more frequent in those with a recent onset (<3 years) of diabetes (13.7% (8/58)) than in those with a longer history (>3 years, 3.8% (4/105)). Furthermore, intraductal papillary mucinous neoplasm (IPMN) is reported to be associated with pancreatic carcinoma. Concomitant carcinoma was found in 9 of our series of 94 patients (9.5%) who underwent surgical resection of branch duct IPMN. Of particular interest is the fact that two of the 9 patients had carcinoma in situ that could be diagnosed only by cytology of the pancreatic juice. IPMN may be the only clue to the early diagnosis of pancreatic carcinoma presenting with no clinical symptoms or abnormalities on imaging studies.