Radiochemotherapy of malignant glioma in adults. Clinical experiences

Standard treatment in patients with malignant glioma consists of surgery and postoperative radiotherapy. A high early recurrence rate, particularly in glioblastoma, has led to the investigation of additional chemotherapy.

Recent results of radiochemotherapy published in the literature were reviewed with respect to outcome in phase II and III trials. Based on these experiences, aspects of future strategies were discussed.

3 decades of intensive research had, unfortunately, little impact on the overall results. While early prospective studies established adjuvant nitrosoureas, particularly BCNU, as suitable adjuvant to surgery and postoperative radiotherapy, further studies largely concentrated on combined chemotherapeutic protocols, mostly procarbazine, CCNU and vincristine (PCV), which was shown to prolong survival in anaplastic astrocytoma. The recent MRC study, however, showed no effect for adjuvant PCV in grade III and IV malignant glioma. Only in high-grade glioma with an oligodendroglial component, additional chemotherapy may be of a decisive benefit. The introduction of newer drugs such as paclitaxel, temozolomide, or gemcitabine demonstrated no decisive advantage. Different modes of application and sequencing of radiotherapy and chemotherapy are presently actively investigated, but failed to substantially improve outcome.

Therefore, search for newer and more effective drugs continues, as well as for "optimal" administration and sequencing, especially from the standpoint of accompanying acute and late toxicity. Finally, recent endeavors focused on basic research such as angiogenesis, migration and invasion, or induction of cell differentiation, but these strategies are still away from broader clinical investigation.