[An unusual case of hydatid cyst].

A hydatid cyst of the spleen developed in a Greek-Canadian woman who had lived on a sheep farm. The cyst extended through the diaphragm to the left lower lobe. Splenectomy and left lower lobectomy and excision of contiguous diaphragm were performed. Histopathologic examination confirmed the presence of hydatid cysts in both spleen and lung. Postoperative course was uneventful. In Canada hydatid disease is rare and its occurrence sporadic. It is commoner among Canadian Indians and immigrants than native Canadians. Treatment is surgical; en bloc excision of tissue eliminates the possibility of anaphylaxis of dissemimination of scolices.