Pediatric inflammatory myofibroblastic tumor with late metastasis to the lung: case report and review of the literature.

Inflammatory myofibroblastic tumors (IMTs) are challenging lesions with respect to classification, differential diagnosis, and biologic potential. In children, extrapulmonary IMTs, particularly those from the abdomen or mesentery, are generally aggressive, with frequent local recurrences. There are few documented patients with distant metastasis, and most of these had metastases at presentation or developed metastases within months to a few years.