PROGNOSTIC-SIGNIFICANCE OF PREOPERATIVE MRI SCANS IN GLIOBLASTOMA-MULTIFORME

Tumor necrosis, enhancement, and associated edema in patients with gli oblastoma multiforme (GEM) represent biological variables that can be quantitated on preoperative MRI scans. We reviewed 48 highly selected patients, all of whom had supratentorial lesions, had undergone gross total tumor resection, and had received adjuvant treatments (radio- an d chemotherapies). None of these patients had had surgery for recurren t tumor resection and none had harbored multifocal tumors. The median age was 50 years. The median Karnofsky performance score was 80. Multi variate analysis using the Cox regression model revealed that the stro ngest prognostic variable was the amount of tumor necrosis on preopera tive scan (P < 0.001), with median survivals of 42, 24, 15, and 12 mon ths for tumor necrosis grades of 0 (7 'pts'), I (11 'pts'), II (9 'pts '), and III (21 'pts'), respectively. The intensity of enhancement of the tumor nodule was another prognostic factor (P = 0.003), with media n survivals of 35, 18, and 13.5 months for enhancement grades of 0 (2 'pts'), I (22 'pts'), and II (24 'pts'), respectively. The extent of p eritumoral edema had a quadratic effect (P = 0.001), with grades I (19 'pts'), II (22 'pts'), and III (7 'pts') surviving for 24, 12, and 20 months respectively. Location and volume of tumors were not statistic ally significant predictors of survival (P < 0.05). In conclusion, in this highly selected group, GEM patients with little or no necrosis an d with less tumor nodule enhancement on preoperative MRI survive longe r than patients with greater amounts of necrosis and greater degrees o f tumor enhancement. In addition, a moderate degree of peritumoral ede ma is associated with worse prognosis.