Figure 4: Relationship between preoperative Karnofsky performance status score (KPS) and tumor grade according to the proposed new classification system for craniopharyngiomas. Preoperative KPS decreases significantly corresponding to an increase in tumor grade. Mean preoperative KPS is 79.5 ± 13.1 for grade II (n=38), 73.1 ± 9.7 for grade III (n=45), 64.4 ± 18.6 for grade IV (n=16) is, and 40.0 for grade V (n=1). Gamma knife (GK) treatment (right lower panel) (preoperative; n=15, postoperative; n=13, total; n=28) or surgery in other institution (right upper panel: previous Op. in other institute; n=14) does not influence preoperative KPS score. GK+; GK treatment before or after surgery, GK-; No GK treatment, Previous Op. in other institute; 1st operation done in other institution, Previous Op. (-); primary surgery done in our institution.