In order to assess the value of serum markers and simple clinical data in the differential diagnosis of pancreatic cancer, we studied 32 control subjects and 28 patients with pancreatic cancer, 26 with chronic pancreatitis, and 37 with extra-pancreatic diseases. CA 19-9 was found to be the best marker in detecting pancreatic cancer. Among the clinical data, presence and onset of pain attacks, age, and weight loss were selected as the most informative in assessing chronic pancreatic disease. Clinical data correctly classified 88.5% of chronic pancreatitis and 75.0% of pancreatic cancer; serum markers identified pancreatic tumor in 67.9% of the patients. The adjunct of serum markers to clinical data did not improve accuracy in diagnosing chronic pancreatic disease. Since clinical data and serum markers generally become positive at an advanced stage of the disease, early diagnosis of pancreatic cancer is a goal still to be attained.