Purpose: This study investigates the response rate to and toxicity of carboplatin and vincristine in children with recurrent low-grade gliomas (LGGs) or patients younger than 60 months with newly diagnosed LGGs.
Patients and methods: Twenty-three children with recurrent and 37 children with newly diagnosed LGGs were treated with a 10-week induction cycle of carboplatin and vincristine, followed by maintenance treatment with the same drugs. Patients were evaluated for response to treatment and toxicity.
Results: Twelve of 23 (52% +/- 10%; 95% confidence interval [CI], 0.32 to 0.72) assessable children with recurrent disease had an objective response to treatment, which included a greater than 50% reduction in tumor size in seven of 23 (30% +/- 10%; 95% CI, 0.10 to 0.50). Twenty-three of 37 (62% +/- .08; 95% CI, 0.46 to 0.78) of newly diagnosed patients had an objective response, 16 of 37 (43% +/- 0.08%; 95% CI, 0.27 to 0.59) with greater than 50% reduction in tumor size. The majority of those with an objective response had diencephalic tumors (n = 29), but children with thalamic (n = 2), cortical (n = 1), and brain stem (n = 2) LGGs also responded to treatment. Of the 35 patients with objective response to treatment, the maximum response was seen in 25 after completion of induction and in the remaining 10 after two to six cycles of maintenance treatment. Forty-nine of 53 (92% +/- .04%) patients who were stable or improved after induction remain without progressive disease (PD). Hematologic toxicity was common, but resulted in cessation of therapy in only one patient. Six children have been removed from the study because of allergic reactions, which were considered to be carboplatin-associated.
Conclusion: Carboplatin and vincristine have activity in children with recurrent and newly diagnosed progressive LGGs. Objective responses to treatment after chemotherapy can be seen. This drug regimen is relatively well tolerated, and further studies are indicated to define the role of this combination of drugs in children with newly diagnosed LGGs.