There is a large well-circumscribed retroperitoneal cystic mass arising from the right iliacus muscle measuring (20x14x12 cm), composed of multiple peripheral daughter vesicles with a central solid matrix. It shows upward extension, displacing the right kidney as well as the caecum and ascending colon anteriorly. Note mild cortical erosion of the adjacent iliac bone.
Small cysts are noted in the segments II and IV of the liver (simple hepatic cysts confirmed by ultrasound).
No pulmonary hydatid cyst is seen.