Inflammatory myofibroblastic tumors in children: a single-center retrospective study of clinical features, management, and outcomes.

Background: Inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal neoplasm of intermediate malignant potential. While its clinicopathologic features have been described in adults, comprehensive data in the pediatric population remain limited. Methods: We retrospectively reviewed pediatric patients diagnosed with IMT at Shanxi Provincial Children's Hospital between January 2016 and June 2024. Clinical data, imaging, histopathology, immunohistochemistry (IHC), and outcomes were systematically analyzed. Results: A total of 16 patients with complete clinical data and follow-up information were included. There were 10 male and 6 female patients, with a median age of 5.0 years. The primary tumor locations and clinical manifestations were diverse: 8 cases were located in the abdominal and pelvic cavities, presenting with abdominal pain, nausea, vomiting, and fever; 4 cases were located in the head, neck, and facial region, with 3 presenting as painless localized masses and 1 with inspiratory dyspnea; 1 case each occurred in the chest wall, gluteal region, and left upper limb, all presenting with painless localized masses; and 1 case occurred in the lung, presenting with cough, sputum, and recurrent respiratory infections. All 16 patients underwent surgery; three developed local recurrence requiring re-operation. At last follow-up, 15 were disease-free and one remained stable on ALK-targeted therapy. Conclusion: Pediatric IMT is a rare, low-grade malignancy with favorable prognosis. Complete surgical resection remains the cornerstone of treatment. ALK-targeted therapy may benefit patients with unresectable or recurrent disease. Long-term surveillance is warranted due to the risk of recurrence.