Inflammatory pseudotumor of the retroperitoneum in a child.

Inflammatory pseudotumor is a rare, benign lesion of various organs and tissues that occurs in children and young adults. A case is reported in a 12-year-old boy in a retroperitoneal location with involvement of the left ureter and a thrombosis of left iliac vein. He underwent surgical resection. A local recurrence 6 months later was surgically cured.