Temozolomide chemoradiation improves survival in high risk low grade gliomas in phase II trial.
The role of adjuvant chemotherapy in patients with low grade gliomas remains unclear. The authors report initial results from a phase 2 clinical trial (RTOG 0424) in which 129 patients with high-risk low grade gliomas (LGG) were treated with radiation (54 Gy in 30 fractions) and concurrent and adjuvant temozolomide after surgery. All patients had at least 3 of the 5 high-risk factors, including age over 40 years, preoperative tumor diameter ≥ 6 cm, bilateral tumor, astrocytoma component in histology and preoperative neurologic deficits. Results were compared to historical controls. Among the 129 patients, the three-year overall survival was 73.1%, which was significantly higher than the historical control of 54%. Three-year progression-free survival was 59.2%. The primary limitation of this manuscript is the comparison to historical control data published in 2002. Potential differences in imaging evaluation, surgery, radiation therapy, and timing of adjuvant treatment over this time frame may confound the comparison. Also, the authors of the study do not provide stratification of the results based on pretreatment characteristics such as extent of resection (biopsy vs. total) or histology subtype (e.g. astrocytoma vs. oligo-astrocytoma). This manuscript addresses an important topic in management of high-risk patients with low-grade glioma, and contributes to emerging reports indicating improved survival with the use of adjuvant chemotherapy and radiation in these patients.