Impact of treatment on survival of patients with secondary glioblastoma

Data concerning treatment of secondary glioblastoma evolving from previously treated WHO II or III grade tumors are very scarce. The aim of this study was to evaluate the impact of surgical resection and adjuvant treatment on survival in patients with secondary glioblastoma. Thirty-nine patients with secondary glioblastoma evolving from previously treated lower grade gliomas between 2004 and 2015 were included. We evaluated the extent of resection, pathological parameters, adjuvant treatment, as well as survival after malignant transformation. The primary tumor grade was WHO II in 16 (41.0%) and WHO III in 23 (59.0%) patients. Median age was 43 years (range 23-67). Median KPS was 80 (range 60-100) before surgery, and 70 (range 50-100) after surgery. Gross total resection (GTR) of contrast-enhancing disease was achieved in 19 (48.7%) patients. Adjuvant treatment was radio-chemotherapy in 23 (59.0%), radiotherapy in three (7.7%), chemotherapy in five (12.8%) and none in eight (20.5%) patients. Median survival was 11 months (range 1-35) in the entire group. Time since initial diagnosis and previous treatment did not correlate with survival after glioblastoma. Failed GTR, poor KPS after surgery, and no adjuvant treatment were prognostic factors for shorter survival in univariate analysis (p < 0.0001, p = 0.028 and p = 0.003). In selected patients, complete resection and adjuvant treatment may prolong survival in spite of multiple previous therapies.