Prognostic markers for immunochemotherapy using tegafur -uracil (UFT) and protein-bound polysaccharide K (PSK).

AIM/BACKGROUNDWe previously reported that PSK-induced lymphocyte blastogenesis reaction (PSK-stimulation index; PSK-SI) may be a prognostic marker for immunochemotherapy using PSK in gastrointestinal cancer patients. In this study we evaluated the usefulness of PSK-SI as a prognostic marker for PSK therapy at higher and lower serum immunosuppressive acidic protein (IAP) levels.PATIENTS AND METHODS98 gastric and 135 colorectal cancer patients were analyzed. PSK-SI and serum IAP levels were measured preoperatively. After operation, patients received UFT and PSK for two years.RESULTSThere were no differences between patients with higher and those with lower PSK-SI with respect to the clinicopathological factors. In patients with higher serum IAP levels (> or = 500 microg/ml), recurrence-free survival (RFS) and overall survival (OS) were apparently more favorable in the higher PSK-SI group (gastric cancer; > or = 1.75, colorectal cancer; > or = 2.1) than in lower PSK-SI group, although the differences were not significant.CONCLUSIONSerum IAP levels and PSK-SI may be useful markers for prediction of response to immunochemotherapy using PSK, although further studies are necessary.