[Unusual mediastinal cystic lymphangioma. Apropos of a case and review of the literature].

Cystic lymphangioma is an uncommon congenital neoplasm which frequently occurs in young adults. Less than 1% are localized in the mediastinum. The authors report the case of an unusual voluminous mediastinal cystic lymphangioma, with a fatal outcome in a twelve year old boy. The authors recall the histological and clinical characteristics of these tumors and the possibility of the radiologic diagnosis based on ultrasound, CT and MRI sites. The radiological findings are the same as for other sites of cystic lymphangioma in adults. Imaging guided cytologic puncture, when positive, may help to characterize these tumors.