Purpose: This retrospective study evaluated immunity in elderly patients with unresectable gastric cancer receiving S-1/ Lentinan combination chemotherapy.
Patients and methods: This study included 10 patients aged≥70 years with unresectable gastric cancer who received S-1/Lentinan combination chemotherapy between October 2008 and December 2012. All patients gave written informed consent. Immune parameters for regulatory T cell(Treg)ratio, prostaglandin E2(PGE2), C3, CH50, and granulocyte/lymphocyte ratio were measured before chemotherapy initiation and at 7 weeks after it. Clinicopathological or immune parameters affecting overall survival(OS)were consequently evaluated.
Results: A high Treg ratio(p=0.02) and low PGE2(p=0.05)levels at 7 weeks after chemotherapy and a decrease in the Treg ratio(p=0.02)were found to be significant favorable factors affecting OS.
Conclusion: The outcome of elderly patients with unresectable gastric cancer receiving S-1/Lentinan combination chemotherapy seemed to be correlated with the change in immunity.