Klippel-Trenaunay syndrome is a rare congenital disorder characterized by combined vascular malformations, varicosities, and limb enlargement. A child case of Klippel-Trenaunay syndrome with a large cervicomediastinal cystic lymphatic malformation and a vascular mass on the chest wall has been presented to demonstrate combined use of conservative and surgical approaches in this syndrome. Cystic lymphatic malformation was treated by sclerotherapies including ultrasound-guided transthoracic bleomycin injection into mediastinal cyst, which was tried for the first time in the literature, and vascular chest wall tumor necessitated surgical excision. (c) 2006 Elsevier Inc. All rights reserved.