The use of temozolomide in recurrent malignant gliomas

Gliomas are the most common primary intracerebral tumours and over 60% of these are malignant. Standard treatment in the UK for patients with a good performance status consists of surgery and postoperative radiotherapy, however, recurrence is almost inevitable. Treatment of recurrent malignant gliomas (MG) is limited to further surgery, chemotherapy and novel biological therapies. The response rate to standard chemotherapy protocols for recurrent MG is less than 30%. Temozolomide (Temodar-US, Temodal-Rest of World) is an oral alkylating agent with a similar chemical structure to dacarbazine, and has recently been licensed in the UK for second line treatment of recurrent MG. Several phase II studies and one randomised trial suggest that Temozolomide improves time to progression and quality of life but not overall survival. The drug is well tolerated with dose limiting myelosuppression and thrombocytopenia occurring in less than 10% of patients at current dosage schedules. A randomised trial comparing Temozolomide with best first line adjuvant chemotherapy (PCV) is about to start recruiting patients. Further clinical studies investigating its role in neoadjuvant treatment or in combination with radiotherapy or other chemotherapeutic approaches are ongoing.