Efficacy and Safety of Trametinib Therapy for Complex Lymphatic Malformations

This study evaluated trametinib in five pediatric patients (median age 9 years) with complex lymphatic malformations, such as kaposiform lymphangiomatosis (KLA) and generalized lymphatic anomaly (GLA). All showed significant clinical improvement: coagulopathy resolved (platelet increase 54%-362%, D-dimer decrease > 91%), 80% achieved partial response radiographically, and toxicity was minimal (one Grade 2 rash). NRAS proto-oncogene mutations were detected in 80% of cases, but clinical benefit occurred without mutation. Trametinib is an effective, safe, first-line therapy for KLA/GLA.