Inflammatory myofibroblastic tumors are rare benign mesenchymal neoplasms composed of myofibroblastic cells intermixed with an inflammatory infiltrate of cells including plasma cells, lymphocytes, and histiocytes. These tumors are commonly seen in children and are rare in adults. Management of these tumors is challenging due to their unpredictable behavior. Here, we present a rare case of a pulmonary inflammatory myofibroblastic tumor that regressed spontaneously following a minimally invasive computed tomography-guided percutaneous lung biopsy.