A comparison of treatment results for recurrent malignant gliomas

Retreatment of malignant gliomas may be performed with palliative intent af ter careful consideration of the risks and benefits, and with special regar ds to iatrogenic neurotoxicity and quality of life (QOL). This review compa res studies of several retreatment strategies (published between 1987 and 2 000) based on the quality of their evidence. Depending on both established prognostic factors and previous treatment, individually tailored retreatmen t strategies are possible. In all studies that included a multivariate anal ysis of prognostic factors, performance status was the most important. So f ar; predictive factors for response. which might facilitate patient selecti on, have not been unequivocally defined. In terms of QOL, single-agent chemotherapy (temozolomide, nitrosoureas, pla tinum and taxane derivatives) may offer a better therapeutic ratio than pol ychemotherapy. For glioblastoma multiforme, progression-free survival and Q OL were more favourable after temozolomide than procarbazine (level 1 evide nce). The survival of patients after various radiotherapy techniques is broadly s imilar: However, considerable toxicity is associated with radiosurgery or b rachytherapy. Fractionated stereotactic radiotherapy plus radio-sensitizing cytostatic agents has shown promising initial results in small groups of s elected patients and awaits further evaluation. Level 2 evidence derived fr om non-randomized studies does not suggest a substantial prolongation of su rvival by re-resection as compared with chemotherapy or radiotherapy alone. Level 1 evidence derived from a randomized trial suggests that application of BCNU polymers significantly improves the outcome after re-resection. Ho wever: most studies reported median survival in the range of only 25-35 wee ks, thereby emphasizing the need for the development and clinical evaluatio n of new innovative treatment approaches. (C) 2000 Harcourt Publishers Ltd.