KIF18A and neoplasm: To deeply explore the potential biological functions of KIF18A and further explain why high expression of KIF18A is associated with poor prognosis of patients, we conducted immune infiltration analysis based on the ssGSEA algorithm; the results indicated that the expression level of KIF18A was prominently correlated with Th2 cells and tumour-associated macrophages (TAMs), and the numbers of these two kinds of cells in the patient group with high expression of KIF18A were both highly expressed with significant statistical differences.