[Macrocystic lymphatic lymphangioma (cystic lymphangioma) of the upper extremity: a case report].

We report on a case of macrocystic lymphatic malformation of the forearm. A male infant, without any medical history, was followed up in our department since the age of 7 months because of a subcutaneous, soft, painless mass of the left forearm. Ultrasonography and the magnetic reasonance imaging (MRI) were evocative of a macrocystic lymphatic malformation. Five sessions of sclerotherapy led to the reduction of the size of the mass but another axillary tumor appeared afterwards. A surgical excision, unfortunately incomplete, was performed rapidly followed by a recurrence of the macrocystic lymphatic malformation. Macrocystic lymphatic malformations are localized in the neck in 75% and axilla in 20% of the cases. Involvement of the upper extremity and particularly the forearm is very rare. MRI is useful for the diagnosis and the definition of tumor limits. The treatment is usually challenging because of their location and rough delimitation.