Inflammatory myofibroblastic tumors in children: clinical characteristics and treatment outcomes with a focus on targeted therapies.

Abstract

Background: Inflammatory myofibroblastic tumors (IMTs) are rare neoplasms in children. Traditionally, surgical resection has been the primary treatment modality with limited efficacy reported for conventional chemotherapy and radiation therapy. Recently, targeted therapies have emerged as potential options for selected cases. This study aimed to evaluate the demographic, clinical, laboratory, and radiological characteristics, as well as treatment outcomes, in children diagnosed with IMTs.

Methods: This study involved a retrospective review of medical records for eight children diagnosed with IMTs between 1990 and 2022. We collected demographic, clinical, laboratory, and radiological data, as well as treatment outcomes. Data on tumor characteristics, surgical procedures, and chemotherapy or targeted therapy treatments were extracted.

Results: The mean age at diagnosis was 9 years. None presented with metastatic disease at the time of diagnosis. Anaplastic lymphoma kinase (ALK) positivity was identified in tumor tissue from five patients. Among the six patients who underwent surgical resection, three achieved negative surgical margins. Of the three patients with positive surgical margins, one underwent re-resection, local and metastatic recurrences were noted in another, and one was started on crizotinib. A patient with an inoperable tumor at diagnosis was initiated on crizotinib and achieved complete remission. Ceritinib was administered to a patient with YWHAE-ROS fusion, resulting in more than 90% reduction in tumor volume. The median follow-up time was 67.5 months. The five-year overall survival and event-free survival rates for the cohort were 85.7% and 72.9%, respectively.

Conclusions: While surgical resection remains the cornerstone of treatment for IMTs, favorable outcomes can be achieved with chemotherapy and targeted therapies in selected cases. Increasing the utilization of targeted therapies may be beneficial, particularly through molecular studies aimed at minimizing the side effects associated with conventional chemotherapy.