Abstract
Inflammatory myofibroblastic tumor （IMT） is a rare mesenchymal soft tissue tumor characterized by borderline or low-grade malignancy. It is rare childhood tumor with an average age of onset of 10 years old. It is even rarer in infants and toddlers, and the etiology and pathogenesis of this tumor are still unclear. The clinical presentation of IMT is non-specific and are related to the location of the tumor. When the tumor compresses adjacent organs, it can cause pain and functional impairment. According to the current literature, IMT is most commonly found in the digestive and respiratory systems, but also occasionally occur in the genitourinary system, head and neck, and limbs. At present, there have been no reports of nasopharyngeal IMT involving nasal cavity of infants and toddlers at home and abroad.This article reports a case of a massive inflammatory myofibroblastic tumor involving the nasal cavity and nasopharynx in an infant. Plasma-assisted minimally invasive surgery was performed through multiple surgical approaches and achieved satisfactory therapeutic results. This case report may provide valuable reference for the treatment of similar diseases.