[Molecular targeted therapy for progressive low-grade gliomas in children].

Objectives: To evaluate the efficacy of molecular targeted agents in children with progressive pediatric low-grade gliomas (pLGG).

Methods: A retrospective analysis was conducted on pLGG patients treated with oral targeted therapies at the Department of Pediatrics, Beijing Shijitan Hospital, Capital Medical University, from July 2021. Treatment responses and safety profiles were assessed.

Results: Among the 20 enrolled patients, the trametinib group (n=12, including 11 cases with BRAF fusions and 1 case with BRAF V600E mutation) demonstrated 4 partial responses (33%) and 2 minor responses (17%), with a median time to response of 3.0 months. In the vemurafenib group (n=6, all with BRAF V600E mutation), 5 patients achieved partial responses (83%), showing a median time to response of 1.0 month. Comparative analysis revealed no statistically significant difference in progression-free survival rates between the two treatment groups (P>0.05). The median duration of clinical benefit (defined as partial response + minor response + stable disease) was 11.0 months for vemurafenib and 18.0 months for trametinib. Two additional cases, one with ATM mutation treated with olaparib for 24 months and one with NF1 mutation receiving everolimus for 21 months, discontinued treatment due to sustained disease stability. No severe adverse events were observed in any treatment group.

Conclusions: Molecular targeted therapy demonstrates clinical efficacy with favorable tolerability in pLGG. Vemurafenib achieves high response rates and induces early tumor shrinkage in patients with BRAF V600E mutations, supporting its utility as a first-line therapy.