RESUMEN
Inflammatory myofibroblastic tumor (IMT) is a rare neoplasm mostly seen in the lungs, but also in extrapulmonary sites. The most common genitourinary site of IMT is the bladder, but it may rarely be seen in the kidneys. We report a case of a 15-year-old girl presented with flank pain and hematuria, in which computed tomography scan revealed a mass in the left kidney. The patient underwent left nephrectomy for a diagnosis of Wilms tumor. Further assessment of the tissue demonstrated a pathologic diagnosis of IMT. Despite improvements in imaging technology, the preoperative diagnosis of IMT remains difficult and surgery is the only way for the diagnosis and treatment. Considering the role of the pathologic examination in making the definite diagnosis of IMT, we should be aware of this entity and it must be considered in the differential diagnoses.