Inflammatory myofibroblastic tumors in children.

Background: Inflammatory myofibroblastic tumor (IMFT) is an uncommon neoplasm in children.

Methods: Retrospective review from 1993 to 2014 of patients ≤18years of age with a histopathologic diagnosis of IMFT treated at two tertiary centers.

Results: Thirty-two patients were diagnosed with IMFT. Mean (±SD) age was 9.3±5.7years at diagnosis. Tumor location was variable: abdomen/pelvis (28%), head/neck region (22%), intrathoracic (22%), genitourinary (9%), bowel (6%) liver (6%), and musculoskeletal (6%). Median follow-up was 2.6±4.6years, with 3 recurrences and 2 deaths, which occurred only after recurrence. Positive microscopic margin after resection was associated with recurrence, compared to those that had a negative margin (40% vs. 0%, p=0.04). Recurrence was associated with increased mortality (67% vs 0%, p=0.01). Time from first symptoms to resection was shorter in those with recurrence (25.8±22 vs. 179±275days, p=0.01) and in nonsurvivors (44.0±8.0 vs. 194.3±53.4days, p=0.02). Adjuvant chemotherapy, not including steroid monotherapy, either given before or after resection, was administered more often to nonsurvivors (100% vs 4%, p=0.009), and use of corticosteroids was also higher in the nonsurvivors (100% vs. 15%, p=0.04).

Conclusions: IMFT is a rare pediatric neoplasm with variable locations. Complete excision is critical for cure. Proposed guidelines for diagnosis, treatment and surveillance of theses tumors in children are reported.