THE ROLE OF CHEMOTHERAPY IN RECURRENT MALIGNANT GLIOMAS - AN OVERVIEW

First-line treatment of malignant gliomas invariably includes surgery when feasible, and often adjuvant radiotherapy with or without chemoth erapy; at progression or recurrence, the only remaining possibility is chemotherapy. While the role of first-line treatment has been establi shed by many randomized studies. second-line treatment is not as well defined. To analyze the difficulties encountered with cytotoxic drugs in relation to both the blood-brain barrier and drug resistance, we ex amined the results obtained by single-agent chemotherapy, drug combina tions, and biological response modifiers. Our findings confirmed that the nitrosoureas are the most active substances at the time of recurre nce; these agents give an approximately 30% global response rate, with about 20 weeks' survival. Although no comparative randomized studies regarding single- versus multiple-agent chemotherapy are available, th e latter approach, including nitrosourea, can obtain an up to 40% rate of response, with survival ranging from 30 to 50 weeks. The role of i nterferons has been very controversial; individually, alpha- and beta- interferons seem to give a 20% response rate, with 20 weeks' survival. To date, they have never been used in combination with cytotoxic drug s, but they may prove synergistic without increasing toxicity. Studies addressing the quality of life of these patients are not available, a nd it is clear that we need more basic research in this field.