Lymphangiomas are the lymphatic analogue of the haemangioma of blood vessels and are congenital. They are thought to represent isolated and sequestreted segments of the lymphatic system and retain the ability to produce lymph [1
]. Three types of lymphangiomas can occur-cystic, capillary and cavernous [2
]. Cystic type is also known as cystic hygroma and is most common. It consists of lymph filled spaces with thin wall septum and some areas of fibrosis. It is macrocystic lesion and is multilobular, multilocular and brilliantly transilluminant. Majority [75%] of cystic hygroma occur in neck. Axilla is the next site of election [20%]. The cheek, axilla, groin and mediastinum are other less frequent sites for a cystic hygroma [3
]. When the cystic hygroma of neck is unilocular it is termed as hydrocele of the neck [4
]. Likewise hydrocele of the breast has also been described. So far very few cases of classical congenital cystic hygroma [lymphangioma] of thigh have been reported. However few cases of traumatic cystic hygroma have also been reported in literature [5
]. No case report of unilocular cystic hygroma could be found in the literature even after extensive search on net. We are of the view that it can be better termed as hydrocele of thigh. The treatment is surgical excision which although frequently incomplete is rarely associated with recurrence.
Sclerotherapy is also helpful.