Helicobacter pylori Modulated Host Immunity in Gastric Cancer Patients With S-1 Adjuvant Chemotherapy.

Background: Paradoxically, Helicobacter pylori-positive (HP+) advanced gastric cancer patients have a better prognosis than those who are HP-negative (HP-). Immunologic and statistical analyses can be used to verify whether systemic mechanisms modulated by HP are involved in this more favorable outcome.

Methods: A total of 658 advanced gastric cancer patients who underwent gastrectomy were enrolled.