Primary axillary hydatid cyst.

Echinococcosis is a zoonotic infection, affecting humans in a characteristic geographic distribution. The disease generally involves the liver, the lung and sometimes an axillary location. We reported a case of 43-year-old man, who was diagnosed with a cystic lesion of the left axilla, which was presumed to be a hydatid cyst or a vascular malformation by ultrasound and computed tomography. Surgical excision of the lesion was performed confirming the hydatid cyst diagnosis by histological studies.