Cystic hygroma of the breast: a rare lesion.

Lymphangiomas are congenital malformations of lymphatic vessels. More than 50% of these lesions are present at birth; 90% are diagnosed by the age of 2. These lesions do not expand very rapidly but they tend to infiltrate surrounding tissues; their degeneration into malignant tumors is an extremely rare occurrence. They are mostly located in the neck region and the axilla; breast lymphangioma is very rare. Surgery is usually performed for aesthetic reasons and in order to make a differential diagnosis with other, more common lesions. The surgical procedure involves the excision of the mass; other methods, such as radiotherapy and sclerotherapy, have proved to be completely ineffective.