Single-Agent Oral Vinorelbine in the Treatment of Pediatric Progressive Optic Pathway Glioma: A Single Institutional Experience

Purpose: The vinca alkaloids’ activity against pediatric low-grade glioma (PLGG) is well established. The goal of the present study is to describe our experience with oral vinorelbine in patients with progressive optic pathway glioma (OPG), not only regarding the clinical response, but also the cost benefit using an oral medication. Methods: Patients under 21 years of age with unresectable and/or progressive OPG were eligible. Oral vinorelbine was administered at a dose of 90mg/m2 daily on days 0, 8 and 22, in a scheme of 4 weekly cycles for a total of 18 cycles (54 doses). Results: From 2013 to 2018, sixteen patients were enrolled onto the study, with a median age of 9,1 years (range 4,6-17,8y). The most common histology was pilocytic astrocytoma (88,8%). Best response to chemotherapy was reviewed with a response rate (complete, partial, or minor response) of 30% for the patients treated exclusively with the oral drug. Five-year event-free survival (EFS) rate was 43.4%. Six patients had to change to intravenous vinorelbine due to gastrointestinal toxicity, vomiting grade III. None of the patients showed neurotoxicity. The total cost including drug acquisition, administration and toxicity management was lower with the oral formulation comparing to IV one. Conclusion: Single-agent oral vinorelbine seems to have some clinical activity in the management of recurrent or refractory pediatric OPG, being an interesting and cost-effective option, minding that gastrointestinal toxicity may be limiting and a combination of antiemetics should be considered in this treatment regimen.