Ectopic production of a salivary type amylase by adenocarcinoma cells: demonstration by a culture technique.

Characterization of an elevated amylase activity in ascitic fluid obtained from a patient with carcinomatous peritonitis is described; ninety-one percent of the increased amylase activity in the fluid was of salivary type and the remainder of pancreatic type, when studied by ion-exchange chromatography. Culture of ascitic cells successfully demonstrated morphologically characterized tumor cells surviving for at least 31 days. During that period, significant amylase activities were detected in the culture media, and the isozyme pattern was a single band whose electrophoretic mobility corresponded to salivary amylase. The data obtained indicate that the ascites amylase of salivary type was produced ectopically by the tumor cells.