Alterations in plasma sialyltransferase levels in patients with neoplastic disease.

Levels of glycoprotein:sialyltransferase activity (EC 2.4.99.1; CMP-acetyl-neuraminate:D-galactosyl-glycoprotein N-acetylneuraminyl-transferase) were measured in plasma of patients with neoplastic disease, and were found elevated above normal control values in 85% of patients examined. There was a correlation between enzyme levels and course of disea-e in 46 of 57 patients studied serially during therapy. Plasma sialyltransferase may be a useful marker enzyme for monitoring effectiveness of therapeutic programs for disseminated neoplasms.