The scores of the Mini‐Mental State Examination (MMSE), prospective and retrospective memory (PM and RM) Questionnaire (PRMQ), and Functional Assessment of Cancer Therapy‐General (FACT‐G) and the levels of cytokines including interleukin‐1 beta (IL‐1β), tumor necrosis factor‐alpha (TNF‐α), and interleukin‐4 (IL‐4) were compared between the two groups. The gene discussed is IL4; the disease is cancer.