Is pancreatic polypeptide a marker for Zollinger-Ellison syndrome?

Basal human pancreatic polypeptide (H.P.P.) concentrations have been measured in 41 pateints with Zollinger-Ellison syndrome (Z.E.S.) and in 100 controls. Basal H.P.P. concentrations in controls varied widely from less than 8 pmol/l (assay detection limit) to 313 pmol/l. In controls, but not in the Z.E.S. patients, there was a highly significant positive correlation between basal H.P.P. and age (P less than 0.01). 4 of the Z.E.S. patients (9.8%) and 3 of the controls (3%) had H.P.P. concentrations over 240 pmol/l. These findings indicate that raised basal H.P.P. concentration is an infrequent finding in patients with gastrinomas and therefore it is not a useful tumour marker.