Mediastinal lymphangiomyoma in a child: report of a case.

Lymphangiomas and lymphangiomyomas are benign abnormal collections of lymphatic vessels which form a cystic mass. The mediastinum is an uncommon location for these hamartomas in children, but may be life-threatening. We report herein the case of a 23-month-old boy who presented with stridor and a history of recurrent respiratory tract infections. Soon after his admission he suddenly developed respiratory failure and was found to have a multiloculated, cystic mediastinal mass which was initially thought to be a lymphangioma. The mass was extensively infiltrative, and histological examination showed prominent smooth muscle proliferation in the walls of the cysts, confirming a diagnosis of lymphangiomyoma. The terminology and relevant literature on the topic are reviewed following the presentation of this case.