LGG-17. Comparing 5-Year Survival Outcomes of Platinum-Based Chemotherapies in Pediatric Low-Grade Gliomas: A Retrospective Cohort Study

Background Low-grade gliomas (LGGs) are the most common brain tumors in children, and platinum-based chemotherapy is often used for unresectable or progressive cases. While carboplatin plus vincristine is the standard regimen, limited data compare its efficacy with other platinum-based combinations. This study evaluates survival outcomes in pediatric LGG patients treated with carboplatin plus vincristine versus carboplatin plus etoposide or cisplatin plus etoposide. Methods Data were retrospectively obtained from TriNetX, an aggregated electronic health records database. Patients younger than 18 with LGG were identified using ICD-10 code C71. Patients receiving chemotherapy primarily indicated for high-grade gliomas, such as temozolomide, lomustine, or bevacizumab, were excluded. Cohort 1 included patients treated with carboplatin plus vincristine, Cohort 2 with carboplatin plus etoposide, and Cohort 3 with cisplatin plus etoposide. Propensity score matching was applied to adjust for demographic differences. After defining the primary outcome as “death,” a Kaplan-Meier analysis was performed, and hazard ratios (HR) and relative risks (RR) were measured. Outcomes were measured within 5 years following the index event. Results 109 patients were included in Cohorts 1 and 2 after matching with no significant demographic differences. Cohort 1 had a survival probability of 96.3% versus 86.7% in Cohort 2 (HR: 0.22, 95% CI: 0.06–0.79, p = 0.0107). However, a non-significant relative risk of death was observed (RR: 0.833, 95% CI: 0.38–1.85, p = 0.6529). In comparing Cohorts 1 and 3, 112 patients were included in each cohort. Cohort 1 had a survival probability of 94.7%, compared to 67.7% in Cohort 3 (HR: 0.14, 95% CI: 0.06–0.31, p < 0.0001), with a significantly lower relative risk of death (RR: 0.29, 95% CI: 0.12–0.43, p < 0.0001). Conclusion Carboplatin plus vincristine may not have a significant survival advantage over carboplatin plus etoposide, but it does show better survival outcomes when compared to cisplatin plus etoposide in pediatric patients with LGGs.