KLK3 and neoplasm: For the XGB model, we identified the feature of importance by the size of the gain value for each variable, with the higher values indicating more importance for the prediction target: GS (158 points), T stage (137 points), PPC (128 points), tumor size (113 points), PSA (88 points), race (64 points), age at diagnosis (51 points), and marital status (36 points) (Figure 4).