IL18 and central nervous system cancer: A total of 119 full‐text articles remained for further evaluation and a final decision, and 88 articles were excluded due to the following reasons: 43 did not assess the relationship between the levels of circulating inflammatory factors with gliomas or their prognostic values in glioma, 33 had no statistical data, five were not full‐text articles, three were reviews, two had a limited number of studies (These two articles studied the relationship between IL‐7 and IL‐18 and gliomas.