IL1B and susceptibility to pneumonia measurement: We selected TNF-α, IL-1β, IL-6, and IL-10 as representative pro-inflammatory, inflammatory, and anti-inflammatory cytokines and investigated the gene promoter polymorphisms of TNF-α -1031 T > C (rs1799964), IL-1β -511 T > C (rs3087258), IL-6 -634G > C (rs1800796), and IL-10 -819 T > C (rs1800871); all of which have been reported to influence cytokine production.18–22 The purpose of this study was to assess whether cytokine promoter gene polymorphisms are associated with the following: (1) perioperative cytokine production and (2) postoperative pneumonia following esophagectomy.