A review of the individual patient data from 12 clinical trials showed that chemotherapy provided a small but significant increase in survival among people with the most common type of brain tumour.
Malignant gliomas are a deadly cancer of the brain and spine, most common in childhood and at age 50-60 years. Treatment generally involves radiotherapy but only half of patients survive more than 9 months after diagnosis. A number of clinical trials since the mid-1960s have looked at whether using chemotherapy as well as radiotherapy would improve survival rates. Most of the trials were too small to clearly show whether there was any effect.
The Glioma Meta-Analysis Trialists group was formed in the late 1990s to look at all of the available evidence to determine whether there was a benefit to treating gliomas with chemotherapy. The group was able to collect individual patient data from 12 trials involving 3004 patients conducted between 1965 and 1997. These trials compared outcomes for patients who were randomly assigned to receive chemotherapy or not in addition to radiotherapy. Combining the data showed that patients who received chemotherapy had a slightly better chance of survival, for example, chances of survival 1 year after diagnosis increased from 40% to 46%. This analysis was the first clear evidence for the benefit of chemotherapy for people with glioma.
This review encouraged further research into new chemotherapy drugs for treatment of these tumours.
This post is part of a series on the value of sharing individual patient data.
Glioma Meta-analysis Trialists (GMT) Group, “Chemotherapy in adult high-grade glioma: a systematic review and meta-analysis of individual patient data from 12 randomised trials.” Lancet. 2002 Mar 23;359(9311):1011-8. Abstract.