Inflammatory myofibroblastic tumor suspected of being a malignant tumor arising in the anterior mandible

Inflammatory myofibroblastic tumors are a neoplastic lesions consisting mainly of myofibroblast proliferation, accompanied by marked infiltrations of inflammatory cells (e.g., lymphocytes and plasma cells); they rarely occur in the jawbone. We describe an inflammatory myofibroblastic tumor that occurred in the anterior mandible and was suspected to be malignant. The patient, a 47-year-old Japanese woman, went to a dentist because of pain in a mandibular anterior tooth. The tooth was extracted due to severe mobility, but after a failure of healing, the patient was referred to our hospital. Compressive bone resorption in the anterior mandible and swelling of both submandibular lymph nodes were observed. Antibiotics were administered, but due to enlargement, a malignant tumor was suspected. FDG-PET and a biopsy were performed. Based on the diagnosis of inflammatory myofibroblastic tumor, tumor resection was performed (general anesthesia). The patient is well at 3 years postsurgery without recurrence or metastasis.