Serum copper and zinc levels and their ratio were evaluated in 48 control subjects, 29 patients with pancreatic cancer, 46 with chronic pancreatitis and 32 with extra-pancreatic diseases, with the purpose of ascertaining modifications in chronic pancreatic disease. Hepatic involvement and age were also investigated as possible factors influencing results. Cu/Zn ratio was found to be significantly increased in pancreatic cancer (2.66 +/- 0.16, mean +/- SE) as compared to controls (1.39 +/- 0.06, p less than 0.001), chronic pancreatitis (1.82 +/- 0.09. p less than 0.001) and extra-pancreatic diseases (1.81 +/- 0.18, p less than 0.001), but without practical clinical value. Serum zinc levels appear to decrease with age, while copper and Cu/Zn ratio increase. However, covariance analysis demonstrated that age does not play an important role in influencing copper and Cu/Zn ratio. A decreased liver synthetic function, at least in part age-related, seems to be an additional factor in decreasing serum zinc values.