Unsuspected giant hydatid cyst of the liver in an 87-year-old woman.

Hydatid cystic disease from Echinococcus granulosus is described in some Brazilian as well as Italian areas. Liver hydatidosis is the most common presentation, which may evolve without symptoms. The authors describe an 87-year-old woman with an unsuspected giant hydatid cyst of the liver and emphasize the diagnostic challenges, mainly involving patients from non-endemic regions.