Metástasis maxilar por tumor miofibroblástico pulmonar detectada en estudio [18F]FDG PET/TC Translated title: Maxillary metastasis due to pulmonary myofibroblastic tumor detected in study [18-F] FDG PET/CT

Inflammatory myofibroblastic tumor (IMT) is a benign lesion that occurs most frequently in the soft tissues and viscera. In the head and neck region, the tumor has been reported to occur in the orbit, tongue, nasopharynx, larynx, and paranasal sinuses and the central nervous system. Despite being a benign lesion, it exhibits infiltrative and destructive behaviours, making histopathological examination necessary to confirm the diagnosis. We report the case of a 38-year-old female presented with a right nasolabial fold mass, which was confirmed histologically to be an IMT. Surgical excision of the mass was achieved through a sublabial approach with an uneventful postoperative period. To the best of our knowledge, this is the first reported case of an IMT in the nasolabial fold.

Inflammatory myofibroblastic tumor (IMT) is an uncommon neoplasm that has been described in various locations throughout the body, but is rarely observed in systemic lymph nodes. We present a case of a 63 years old woman with left inguinal lymphadenopathy accompanied by low-grade fever. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) revealed abnormal higher 18F-FDG uptake on the neck, axillar, pulmonary hilar, mediastinal, mesenteric, retroperitoneal, pelvic and inguinal lymph nodes. These findings led to an initial misdiagnosis of lymphoma. Final histological diagnosis revealed an IMT. The patient was treated with oral steroids. Ultrasound assessments showed a complete resolution of systemic enlarged lymph nodes at the end of 1 month of therapy. There has been no evidence of recurrence through 12 months of post-treatment monitoring. This case suggests that IMT should be considered as a possible differential diagnosis in apparent cases of lymphoma. Further, it indicates that steroid therapy may serve as an effective treatment for IMTs that systemically affect lymph nodes.